dietary habits influence on trace element release from

Dietary habits influence on trace element release

from fixed orthodontic appliances in south Indian

population - In-vitro study

Dissertation submitted to

THE TAMILNADU DR. M.G.R. MEDICAL

UNIVERSITY

For Partial fulfilment of the requirements for the degree of

MASTER OF DENTAL SURGERY

BRANCH - V

ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS

THE TAMILNADU DR. M.G.R. MEDICAL UNIVERSITY

CHENNAI – 600 032

2017 – 2020

ACKNOWLEDGEMENT

I seek the blessings of the ALMIGHTY GOD without whose benevolence this

study would not have been possible. I thank the almighty god in the form of my father

T JAYAPALRAJ, my mother J KALAISELVI, my sister V RAJESWARI for their

blessings, unconditional love, affection, care and prayers. I thank my sweet sister’s daughters V. ANANYA, V. ABHINAYA, and my little prince V. AADHAV

KRISHNA for their unconditional love and affection. Without them, nothing would

have been made possible.

With my heartfelt respect, immeasurable gratitude and honour, I thank my

benevolent guide, Dr. B. BALASHANMUGAM, M.D.S., Professor, Department of

Orthodontics and Dentofacial orthopedics, Tamil Nadu Government Dental College

and Hospital, Chennai – 3, for his astute guidance, support and encouragement

throughout my post graduate course and to bring this dissertation to a successful

completion.

I owe my thanks and great honour to Dr. SRIDHAR PREMKUMAR, M.D.S.,

Professor & HOD, Department of Orthodontics and Dentofacial Orthopaedics,

Tamilnadu Govt. Dental College and Hospital, Chennai - 3, for helping me with his

valuable and timely suggestions and encouragement.

My sincere and heartfelt thanks to Dr. G. VIMALA, M.D.S., our Principal,

Tamil Nadu Government Dental College and Hospital, Chennai – 3, for her continuous

and enormous support in allowing me to conduct this study and for his constant

encouragement and advice during my tough phases in curriculum.

I sincerely thank Professor Dr. G. USHA RAO, Associate Professors Dr. M.

VIJJAYKANTH, Dr. M.D. SOFITHA and Senior Assistant Professors Dr. K.

USHA, Dr. M.S. JAYANTHI, Dr. D. NAGARAJAN, Dr. MOHAMMED IQBAL,

and Dr. R. SELVARANI for their continuous support and encouragement.

I thank my junior Dr. LAKSHMI PRASANNA PALINDLA for her support in

helping and completing my thesis.

I thank my roommates Dr. G.D. RAMKUMAR, Dr. VIJAY SINGH CHAUHAN,

Dr. SENTHIL GANESH, Dr. DASARATHAN for their guidance and who were my

backbone during my entire PG life.

I thank DR. CYRIL BENEDICT for helping me in statistical analysis.

I also thank my post graduate colleagues for their help and constant support.

TRIPARTITE AGREEMENT

This agreement herein after the “Agreement” is entered into on this 27-01-2020

between the Tamil Nadu Government Dental College and Hospital represented by its

Principal having address at Tamil Nadu Government Dental College and Hospital,

Chennai-03, (hereafter referred to as, “the college”)

And

Dr. B. BALASHANMUGAM aged 48 years working as professor at the college,

having residence address at 8-B, Crescent road, Shenoy nagar, Chennai-600030, Tamil

Nadu (Herein after referred to as the ‘Principal investigator’)

And

Dr. J. HARIHARASUDAN aged 27 years currently studying as postgraduate student

in Department of Orthodontics in Tamil Nadu Government Dental College and Hospital

(Herein after referred to as the ‘PG/Research student and co- investigator’).

Whereas the ‘PG/Research student as part of his curriculum undertakes to research

“ Dietary habits influence on trace element release from fixed orthodontic appliances

in south Indian population - In-vitro study ” for which purpose the PG/Principal

investigator shall act as principal investigator and the college shall provide the

requisite infrastructure based on availability and also provide facility to the

PG/Research student as to the extent possible as a Co-investigator.

Whereas the parties, by this agreement have mutually agreed to the various

issues including in particular the copyright and confidentiality issues that arise in this

regard.

Now this agreement witnesseth as follows:

1. The parties agree that all the Research material and ownership therein shall

become the vested right of the college, including in particular all the copyright

in the literature including the study, research and all other related papers.

2. To the extent that the college has legal right to do go, shall grant to license or

assign the copyright do vested with it for medical and/or commercial usage of

interested persons/entities subject to a reasonable terms/conditions including

royalty as deemed by the college.

3. The royalty so received by the college shall be shared equally by all the parties.

4. The PG/Research student and PG/Principal Investigator shall under no

circumstances deal with the copyright, Confidential information and know –

how generated during the course of research/study in any manner whatsoever,

while shall sole vest with the manner whatsoever and for any purpose without

the express written consent of the college.

5. All expenses pertaining to the research shall be decided upon by the principal

investigator/Co-investigator or borne sole by the PG/research student (co-

investigator).

6. The college shall provide all infrastructure and access facilities within and in

other institutes to the extent possible. This includes patient interactions,

introductory letters, recommendation letters and such other acts required in this

regard.

INSTITUTIONAL REVIEW BOARD APPROVAL

PLAGIARISM REPORT

CERTIFICATE II

This is to certify that this dissertation work titled “Dietary habits influence on

trace element release from fixed orthodontic appliances in south Indian

population - In-vitro study” of the candidate Dr. HARIHARASUDAN J with

Registration Number 241719005 for the award of MASTER OF DENTAL

SURGERY in the Branch V – ORTHODONTICS AND DENTOFACIAL

ORTHOPAEDICS. I personally verified the urkund.com website for the purpose of

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ABSTRACT

Background: Dietary habits may adversely affect orthodontic treatment by reduction

in the shear bond strength of brackets, increased risk of dental caries and enamel

microhardness, and change of color stability of orthodontic adhesives and elastic

ligatures. In the current literature, the number of the studies related with the impact of

acidic foods and soft drinks on the corrosion of orthodontic appliances and release of

metal ions is very limited. Metallic orthodontic devices release metals in the presence

of an electrolyte. Metal corrosion may influence both the mechanical behavior and the

appearance of the appliances. Silver-soldered joints are particularly prone to

deterioration, resulting in metal release, surface change, and loss of strength. Both

nickel and chromium can cause dermatitis, asthma, and do have mutagenic and

cytotoxic effect.

Aim: The aim of the study was to investigate the effect of dietary habits on the release

of Ni ions from orthodontic appliances in south Indian population

Objectives: The objective was to elaborate dietary recommendations for orthodontic

patients, in order to diminish the negative effects related with intensified metal ions

release by dietary factors.

Materials and methods: 100 ml of saliva substitute placed in 30 different containers

labelled with each respective dietary sample name. Fixed orthodontic appliances

comprised of brackets, bands, buccal tubes, lingual attachments, archwires were

placed in each container. Each day the fixed orthodontic components were immersed

in the respective dietary samples four times daily for two minutes and then placed

back at the respective glass containers containing artificial saliva.

This procedure is repeated daily for 90 days. The sample of artificial saliva (20ml)

from the glass container is taken into glass tubes with the help of pipette and the glass

tubes are sealed with wooden cork. The samples are tested using Inductive coupled

plasma mass spectrometer (ICP-MS) at three different time periods (1 week , 1 month

and 3 months)

Results: The results revealed that at 1st week time interval, Coca Cola, Thumbs up,

Pepsi showed the highest amount of nickel leach (0.56 mg/l, 0.55mg/l, 0.52mg/l

respectively) into the saliva substitute. After 1 month, the results revealed that Pepsi,

Lemon juice, Red bull, Vinegar showed the highest amount of nickel leached

(1.09mg/l, 0.9mg/l, 0.88mg/l, 0.88mg/l respectively) into the saliva substitute.

3 months interval results show that Pepsi, Coca cola, Red bull, Vinegar showed the

highest amount of nickel leached (2.75mg/l, 2.72mg/l, 2.68mg/l, 2.68mg/l

respectively) into the saliva substitute.

Conclusion: The results suggest that consumption of food products of low pH (such

as Pepsi, Coca cola, Red bull, Thumbs up, lemon juices and vinegar) can intensify

aggressiveness of conditions in the oral cavity and has an effect on increasing the

release of Ni from orthodontic appliances. Therefore, it would be useful to

recommend to orthodontic patients to limit consumption of foods and drinks which

are characterized by low values of pH to reduce the quantity of ions solubilized from

metal alloys.

Keywords: NiTi, SS archwires, Dietary components, Nickel leach, Inductive coupled

plasma mass spectrometer (ICP-MS)

CONTENTS

SL. NO. TITLE PAGE NO.

1. INTRODUCTION 1

2. AIMS AND OBJECTIVES 5

3. REVIEW OF LITERATURE 6

4. MATERIALS AND METHOD 38

5. RESULTS 46

6. DISCUSSION 52

7. SUMMARY AND CONCLUSION 58

8. BIBLIOGRAPHY 63

LIST OF TABLES

SL.

NO. TOPIC PAGE NO.

1 Baseline nickel content present in saliva substitute 46

2 Amount of nickel leach from fixed orthodontic components

into the Saliva substitute from different dietary components

in three different time interval

47

3

Amount of nickel leach from fixed orthodontic components

into the Saliva substitute from different dietary components

in three different time interval after deducting the baseline

nickel content from saliva substitute

48

LIST OF FIGURES

FIGURE NO.

TITLE

1 Orthodontic archwires : NiTi archwires and SS archwires (BROOKLYN

ORTHODONTICSTM)

2 Heat activated nickel titanium archwires (AMERICAN BRACESTM)

3 Brackets (“0.022”-inch slot stainless steel MBT prescription (OrthoxTM)

4 Stainless steel bands (SLR-WELCARE ORTHODONTICSTM)

5 Lingual attachments

6 Buccal tubes

7 Glass tubes with wooden cork

8 Tweezer

9 Glass container

10 Saliva substitute-SALEVATM

LIST OF CHARTS

SL.NO. TOPIC PAGE NO.

1 Nickel leach at 1week interval 50

2 Nickel leach at 1month interval 50

3 Nickel leach at 3months interval 51

LIST OF ABBREVIATIONS

Ni-Ti Nickel Titanium

SS Stainless Steel

Ni Nickel

NA Nickel allergy

ACD Allergic contact dermatitis

Cu Copper

Ag Silver

Pd Palladium

Ni-ACS Nickel-induced allergic contact

stomatitis

ICP-MS Inductive coupled plasma mass

spectrometer

Introduction

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INTRODUCTION

Our diet has an impact on our well-being and on our health1. The effects of

acidic beverages on dental erosion is the result of the enamel and dentin

susceptibility to exogenous acids, originating from acidic food (fruit, yoghurt) or

beverages (fruit juice, energy drinks, cola drinks)2.

Acidic foods and drinks not only have influence on tooth enamel but also reduce

life time of dental restorations. It has been reported that soft drinks affect the

decrease of mechanical properties of restorative materials, especially surface

hardness, surface integrity, and solubility3.

Dietary habits may adversely affect orthodontic treatment by reduction in the

shear bond strength of brackets, increased risk of dental caries and enamel

microhardness, and change of color stability of orthodontic adhesives and elastic

ligatures. In the current literature, the number of the studies related with the

impact of acidic foods and soft drinks on the corrosion of orthodontic appliances

and release of metal ions is very limited4.

Soft drinks contain several acids such as phosphoric, citric, tartaric, lactic, and

maleic acid . Their pH may be close to 2.0 or 3.0, for example, Coca-Cola® 2.3,

Pepsi® 2.3, Sprite® 2.7, Red Bull® 3.1, Powerade® 3.1, orange juice 3.7, white

wine 3.0. 2

Young adults in many parts of the world consume an increasing amount of soft

drinks. The increased consumption has raised several concerns about the health

consequences such as obesity, diabetes, dental caries, dental erosion and mental

health problems5.

Introduction

2 | P a g e

Wide range of appliances routinely applied during orthodontic treatment is made

of alloys which contain cobalt, chromium, iron, nickel, titanium, among which of

the major concern are nickel and chromium. The SS brackets, wires, bands,

auxiliaries as face bow, also elements of removable appliances, contain

approximately 18% chromium, 8% nickel. NiTi wires contain around 47–50% of

NiTi. Nickel is known as strong immunologic sensitizer.4

Metallic orthodontic devices release metals in the presence of an electrolyte.

Metal corrosion may influence both the mechanical behavior and the appearance

of the appliances. Silver-soldered joints are particularly prone to deterioration,

resulting in metal release, surface change, and loss of strength. Furthermore,

brackets with metallic backing may release corrosion products that could discolor

the underlying tooth substance. 6,7

Blanco-Dalmau et al. found 31.9% of the women and 20.7% of the men in a

population of 403 showed a positive reaction to a patch test with nickel sulfate.8

Both nickel and chromium can cause dermatitis, asthma, and do have mutagenic

and cytotoxic effect.9,10,11

Having that on mind, it is important to define amount of metal (nickel and

chromium) released during orthodontic treatment and its influence on an

organism. There are two ways to achieve it: by in vitro and in vivo studies.

In the current literature, the number of the studies related with the impact of acidic

foods and soft drinks on the corrosion of orthodontic appliances and release of

metal ions is very limited.

Nickel and chromium are normally present in the foods consumed by man. Nickel

is the most common cause of metal-induced allergic contact dermatitis and

produces more allergic reactions than all other metals combined, followed by

Introduction

3 | P a g e

chromium. The average dietary intake of nickel is 200–300 μg/day. Nickel aids in

iron absorption, as well as adrenaline and glucose metabolism. It also helps in

improving bone strength and may play a role in the production of red blood cells.

The primary route of eliminating nickel is through the urine.12,13,14

Nickel is ubiquitous and is found in foods (highest in legumes, nuts, grains,

potatoes, chocolate, and fish), tap water, cosmetics, and cooking utensils.15

Barret et al proposed that the acid pH (about pH 6.5), enzymatic activity of the

saliva, organic acids and bacterial flora might provide an environment within the

oral cavity that favours corrosion. The release of metal ions from orthodontic

appliances could, therefore, hypothetically increase the quantity of these ions in

the body to above that ingested with diet and exposure to atmospheric pollution

and/or costume jewellery. 16,17

Nickel allergy (NA) is common with a prevalence of 10–15% and occurs

worldwide.18

The most common manifestation of NA is allergic contact dermatitis (ACD), a

type IV T-cell–mediated delayed-type hypersensitivity reaction. ACD occurs in

areas where skin contacts nickel-containing objects such as costume jewelry,

snaps on clothing, eyeglasses, and watches. Occupational and industrial arenas

also can be a source of nickel exposure. Allergic contact urticaria to nickel has

been reported.19

Characteristic lesions of contact stomatitis vary from barely visible, mild

erythema to a fiery red color with or without edema. Symptoms may include loss

of taste, numbness, burning sensation, and soreness of the involved area, often

accompanied by angular cheilitis. Itching is not a frequent symptom. Although it

is more difficult to provoke contact stomatitis than contact dermatitis, severe

Introduction

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gingivitis associated with orthodontic therapy may be a manifestation not only of

poor oral hygiene but also of a contact hypersensitivity reaction to nickel and/or

chromium ions released during the corrosion of stainless steel.20

Aim and Objectives

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AIM AND OBJECTIVES

NEED FOR THE STUDY

The goal was to elaborate dietary recommendations for orthodontic patients, in

order to diminish the negative effects related with intensified metal ions release by

dietary factors.

AIM

The aim of the study was to investigate the effect of dietary habits on the release

of Ni ions from orthodontic appliances in south Indian population

OBJECTIVES

The objective was to elaborate dietary recommendations for orthodontic patients,

in order to diminish the negative effects related with intensified metal ions release

by dietary factors.

Review of Literature

6 | P a g e

REVIEW OF LITERATURE

Dietary habits affect well-being and health.1 The increased consumption of soft drinks

has raised several concerns about the health consequences such as obesity, diabetes,

hypocalcemia, dental caries, dental erosion, and mental health problems.21,22 The use

of various combinations of metal alloys for prolonged durations in orthodontic

patients warrants special consideration regarding their biocompatibility. The oral

cavity is a complete corrosion cell, with many factors that enhance the biodegradation

of orthodontic appliances.23 Saliva acts as an electrolyte for electron and ion

conduction, and the fluctuation of pH and temperature, the enzymatic and microbial

activity, and the various chemicals introduced into the oral cavity through food and

drink are all corrosion conductors.24

The inherent heterogeneity of each metal alloy and its use with other alloys, the

microsurface discontinuity, the forces acting on the appliances, and the friction

between wires and brackets also add to the corrosion process. It has been reported that

metal ions are taken up by the adjacent oral tissues.25,26,27 An increasing demand for

biocompatibility testing of medical devices has led to the application of different

evaluation methods. In contemporary dentistry, applied materials are being introduced

to the market and frequently one material promptly replaces another, which entails

questions about long-term biocompatibility.28 Orthodontic alloys are made from

various metals, among which chromium and nickel are of major

concern.29,30,31,32,33,34,35,36 Both of these genotoxic, mutagenic, and cytotoxic metals

might induce contact allergy, asthma, hypersensitivity, birth defects, and reproductive

damage.37,38,39,40,41,42,43 Corrosion of orthodontic alloys might lead to release of

considerable amounts of nickel and chromium ions into saliva.44


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The systemic absorption of such metals is an extra health risk.45,46 Despite its

importance, systemic nickel changes during orthodontic treatment have been assessed

merely in a few controversial studies.17,47,48,49,50,51,52 showing systemic increases 47,51

or lack of any significant changes17,47,50,52

Usually, orthodontic treatment with fixed appliances lasts for approximately 2–3

years. Most of the patients are youngsters or adolescents. Some parts of a removable

appliance and all parts of a fixed appliance are manufactured from alloys which

contain nickel and chromium.53 Those metals are well known as sensitizing and

mutagenic agents. This shows that it is important to assess biocompatibility of

orthodontic appliances.54 As pointed out by Wataha, the corrosion of an alloy is of

fundamental importance to its biocompatibility because the release of elements from

the alloy is nearly always necessary for adverse biologic effects such as toxicity,

allergy, mutagenicity, and carcinogenicity. Alloy corrosion provides free ions that

affect the tissues around it. There is little evidence that elements released from casting

alloys contribute significantly to systemic toxicity. The cause of this might be

explained by the low release of ions over time.55 Metal tolerance and the amounts

causing toxicity are not well understood. Metals are not biodegradable, and their

sustained release might produce irreversible toxic effects from their accumulation in

the tissues. Also, the increased exposure could limit the recovery time needed for

cellular repair. Metal toxicity is governed by multiple factors, making it difficult to

truly assess the levels that produce cellular damage.56,57


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STUDIES RELATED TO DIET, NUTRITION CONSIDERATIONS IN

ORTHODONTICS:

Jeevan M. Khatri, Vijaymala D. Kolhe et al (2018)58 Studied the relationship

between diet and orthodontic treatment. A good diet plays an important role in

maintaining good health. With so much focus on healthier foods and more nutritional

food choices, dietary counseling and nutritional education relevant to oral health have

become an important component of dental education. In fact, 1987 guidelines for

accreditation of dental schools by the American Dental Association require that “the

graduate must be competent to provide dietary counseling and nutritional education

relevant to oral health.” Study of diet and nutrition is also a mandatory part of

curriculum in Indian dental schools. Orthodontic treatment creates physical,

physiologic, and emotional stresses that increase the nutrient mobilization and

utilization, thus raising the nutritional requirements of the person. This along with the

fact that the nutritional needs of adolescents (the age of a typical orthodontic patient)

are already stressed by growth and development as well as the emotional stress of

puberty, maintenance of a well‑balanced diet is of great importance. Fixed

orthodontic treatment (braces in common language) typically lasts for around 1½ to 3

years and, during this duration, certain dietary restrictions and modifications are

advised. Typically, the orthodontist often advises their patients to eat soft food during

treatment to avoid pressure sensitivity, but very few give clear‑cut instructions or

provide diet charts. In absence of these, patients generally switch over to convenient

easy‑to‑eat food, without any special attention to the nutrient values of the consumed

food. The literature suggests that orthodontic patients’ nutritional status can affect the

reaction of the tissues to orthodontic forces. Nutritional considerations are most


9 | P a g e

critical during growth and development and environmental challenges. The literature

suggests that the nutritional status of the orthodontic patients can affect the biologic

response of the periodontal ligaments and the bone to orthodontic bands and brackets.

They concluded that to optimize patient’s physiologic response to orthodontic

treatment, it may be beneficial to provide dietary guidance to orthodontic patients in

choosing soft food diets. This includes obtaining nutrition history, evaluating the diet,

educating the patient about diet components important for oral health, motivating the

patient to improve diet, and follow‑up to support patient’s effort to change food

behaviors. Patients with braces who prefer or switchover to convenience foods such

as cakes, pastries, ice creams, and cookies, which are high in simple sugars and fats,

should be advised regarding the value of fruits, vegetables, grains, and cereals in the

irregular diet. Nutrition goals for the orthodontic patient should be to eat a variety of

foods including protein sources, dairy food, fruits, vegetables, and cereals and to limit

salt, fat, and sugar intake.

R Sharma, S Mittal, A Singla, M Virdi et al (2009)59 presented an

overview of the relationship between diet and orthodontic treatment and the

nutritional strategies which can be employed to obtain good oral and general health in

orthodontic patients.. Orthodontic treatment creates physical, physiologic and

emotional stresses that increase the nutrient mobilization and utilization thus raising

the nutritional requirements of the person. This along with the fact that the nutritional

needs of adolescents (the age of a typical orthodontic patient) is already stressed by

growth and development as well as the emotional stress of puberty, maintenance of a

well-balanced diet is of great importance. Fixed orthodontic treatment (braces in

common language) typically lasts for around 1½ to 3 yrs and during this duration

certain dietary restrictions and modifications are advised. Typically the orthodontist


10 | P a g e

often advise their patients to eat soft food during treatment to avoid pressure

sensitivity but very few give clear cut instructions or provide diet charts. In absence of

these, patients generally switchover to convenient easy to eat food, without any

special attention to the nutrient values of the consumed food.

The literature suggest that orthodontic patients nutritional status can affect the

reaction of the tissues to orthodontic forces. Ascorbic acid deficiency for example is

thought to slow down orthodontic tooth movement by decreasing the body’s ability to

heal. Less than adequate levels of ascorbic acid hinder the breakdown and reformation

of collagen which is necessary for tooth movement. About 17-72% of orthodontic

patients have less than optimal levels of ascorbic acid. Retention may also be affected

by ascorbic acid levels as shown by a study in which guinea pigs with deficiency of

ascorbic acid experienced more rapid relapse of malocclusion after treatment than

non-deficient ones. The involvement of certain nutrients in orthodontics has been

looked at in the past, but the diet as a whole has not been evaluated .

They concluded that to optimize patient’s physiologic response to orthodontic

treatment, it may be beneficial to provide dietary guidance to orthodontic patients in

choosing soft food diets. This includes obtaining nutrition history, evaluating the diet,

educating the patient about diet components important for oral health, motivating the

patient to improve diet and follow up to support patient’s effort to change food

behaviors. Compliance with dietary advice is more likely if follow-up is provided.

Dietary progress should be discussed at further appointments. Nutrition care should be

an integral part of orthodontic care.

Stephen F. Litton et al(1974)60 studied the effects of an ascorbic acid deficiency

during tooth movement in guinea pigs to determine what morphologic changes could


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be observed during this vitamin deficiency.

Lack of normal collagen synthesis, because of the lack of ascorbic acid, resulted in an

almost complete cessation of osteogenesis and disorganization of the periodontal

ligament. It appears that ascorbic acid is necessary for the normal morphology of the

periodontal ligament and alveolar bone. This need was accentuated during the

application of light forces which placed a stress on the various tissues.

It has been documented that a relationship exists between collagen synthesis and

ascorbic acid. The lack of ascorbic acid in certain animals, including man, is believed

to prevent the normal hydroxylation of the amino acid proline to hydroxyproline.

Collagen, which contains proline and hydroxyproline, is a major constituent of the

tooth and surrounding supportive structures. During orthodontic tooth movement, the

periodontal ligament and alveolar bone are affected by the application of the

mechanical forces.

The tooth has been reported to be the first system affected in an ascorbic acid

deficiency. Changes include altered morphology of the odontoblast and its process,

hemorrhage of the pulp, osteoid-like formations in the pulp, atrophy of cells, and

cessation of dentin formation. Utilizing isotopic ascorbic acid, some authors have

found label over the odontoblasts of animals deficient in ascorbic acid. They

postulated that, even though there was an altered morphology of the cells, they had

not lost their potential to synthesize dentin.


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STUDIES RELATED TO SOFT DRINKS AND LOW ACIDIC FOODS ON

DENTAL EROSION.

C. Abalos, A. Paul, A. Mendoza, E. Solano, C. Palazon, and F.J. Gil

et al (2013)61 studied the the influence of soft drinks on the surface of Ni-Ti

archwires and their corrosion behavior. the corrosion resistance of Ni-Ti alloys

decreases in acid saliva and chlorine or fluoride-containing solutions. Corrosive

agents deteriorate the passive film of the titanium oxide surface, decreasing corrosion

resistance of the alloy and hence its biocompatibility. carbonated drinks, only studies

on the enamel coating that affects adherence to brackets can be found in the literature.

Such drinks are a part of the diet of young people receiving orthodontic treatment, and

can also degrade the orthodontic archwire surface. When the passive film is broken,

corrosion takes place. As a consequence, the release of metallic ions into the medium,

surface morphological changes including an increase in roughness and friction

coefficient between the archwire and the bracket, are produced. Soft drinks with low

pH values exert corrosive action on the surface of Ni-Ti orthodontic archwires,

although in different ways depending on the surface pattern. Archwires with cracked

or scratched surface patterns are the least corrosion resistant. Cracks as pre-existing

manufacturing defects show the greatest surface deterioration, due to the internal

energy stored. However, the initial roughness of archwires is not related to the

increase in roughness when they are exposed to soft drink. The cracked surface

pattern moreover shows the greatest increase in roughness; therefore, cracks should be

avoided in the archwire surface pattern. The absence of standard surface treatment

protocols for Ni-Ti results in variability in the surface finish, which in turn responds


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differently to corrosion. Such protocols should be helpful in securing better quality

surfaces.

T Attin, K Weiss, K Becker, W Buchalla, A Wiegand et al (2005)2

evaluated the enamel erosive potential of modified acidic soft drinks under controlled

conditions in an artificial mouth. Frequent contact of the dentition with exogenous

acids, originating from acidic food or beverages might result in dental erosion.

Evidence shows that erosion is strongly correlated with the frequency and amount of

soft drink intake. The consumption of soft drinks shows a continuing upward trend

with a distinct increase in several countries. The increasing consumption of acidic soft

drinks appears to be an increasingly important factor implicated in the etiology of

dental erosion. Erosion may be prevented by reducing the intake of acidic foods and

drinks and by modifying drinking habits. Some modifications to acidic beverages

have been suggested to reduce the potential of such drinks to demineralize and

dissolve the mineral compounds of teeth. Additions of hydrocolloids, magnesium,

calcium-citrate-malate, fluoride and calcium/phosphate to soft drinks have been

tested. Studies have shown that high amounts of calcium, phosphate or fluoride were

able to reduce the formation of erosive lesions in enamel distinctly. While

modifications of acidic solutions might lead to reduction of the erosive potential

capacity of the solutions, it is not known, whether these modifications will also reduce

erosive potential of commercial beverages with more complex compositions.

They concluded that modification of the test beverages with low concentrations of

calcium, phosphate and fluoride is able to reduce the erosive potential of the drinks.

However, with these low concentrations enamel dissolution could not be completely

prevented.


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Asmyhr, Grytten J, Holst D et al (2012)21 studied the occurrence of risk

factors for dental erosion for a group of young adults who are particularly susceptible

to erosion. Young adults in many parts of the world consume an increasing amount of

soft drinks. The increased consumption has raised several concerns about the health

consequences such as obesity, diabetes, dental caries, dental erosion and mental health

problems. Traditionally, caries has been regarded as the dental disease that affects

most children and young people in the Western world. This is still true, but during the

last decade, there have been several studies that have shown that erosion is also a

significant dental health problem in these young age groups. Studies show that as

many as 40–50% of 11–14-year-old children have moderate erosion.

They concluded that consumption of soft drinks and juice is high, even though the

awareness and knowledge about the causes of erosion are widespread. Young adults

with mothers with high education drink soft drinks both with and without sugar less

frequently than those who have mothers with low education. This may be a reflection

of a general healthy lifestyle among highly educated people.

STUDIES RELATED TO METAL RELEASE FROM ORTHODONTIC

APPLIANCES

H. Y. Park, T. R. Shearer et al (1983)62 measured the amounts of nickel and

chromium released from a simulated orthodontic appliance incubated in 0.05 percent

sodium chloride solution. They concluded that the average release of metals was 40

ug nickel and 36 ug chromium per day for a full-mouth appliance. This was well


15 | P a g e

below the average dietary intake of nickel and chromium consumed by Americans.

However, the clinician should be aware that release of nickel and chromium from

orthodontic bands might sensitize patients to nickel and chromium and may cause

hypersensitivity reactions in patients with a prior history of hypersensitivity to these

metals.

Characteristic lesions of contact stomatitis vary from barely visible, mild erythema to

a fiery red color with or without edema. Symptoms may include loss of taste,

numbness, burning sensation, and soreness of the involved area, often accompanied

by angular cheilitis. Itching is not a frequent symptom. Although it is more difficult to

provoke contact stomatitis than contact dermatitis, severe gingivitis associated with

orthodontic therapy may be a manifestation not only of poor oral hygiene but also of a

contact hypersensitivity reaction to nickel and/or chromium ions released during the

corrosion of stainless steel.

Nils R. Gjerdet and Hakon Hero et al (1987)63 Studied the release of metals

from cobalt-chromium and stainless steel orthodontic archwires as a consequence of

short-term heating to different temperatures.

They concluded that that the corrosion resistance of stainless steel and cobalt-

chromium wires of the present composition is impaired when the wires are heated

above 400°C, stainless steel being more sensitive than cobalt-chromium. Some

clinical and technologic procedures involve heating to temperatures close to or above

the critical ranges. When heating of orthodontic wires is indicated, the temperature

should be kept as low as possible, and the heating procedure should be well controlled

to minimize corrosion of the appliances.


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Margret Rosa Grimsdottlr, Nils R. Gjerdet et al (1992)64 analyzed

different types of alloys used in orthodontics, and to study whether nickel and

chromium will be released from these alloys when stored in physiologic saline. Face-

bows, brackets, molar bands, and arch wires were analyzed.

They concluded that the release of nickel and chromium seemed to be related to the

composition and the manufacturing of the appliances but was not directly related to

the actual nickel and chromium content. Appliances with silver and gold solders

showed enhanced release of nickel and chromium, whereas alloys containing titanium

released little nickel when tested under static conditions.

Robert D. Barrett, Samir E. Bishara et al (1993)16 compared in vitro the

corrosion rate of a standard orthodontic appliance consisting of bands, brackets and

either stainless steel or nickel-titanium arch wires. The corrosion products analyzed

were nickel and chromium. Evaluation was conducted with the appliances immersed

for 4 weeks in a prepared artificial saliva medium at 37" C.

They concluded that :

1. Orthodontic appliances release measurable amounts of nickel and chromium when

placed in an artificial saliva medium.

2. The nickel release reaches a maximum after approximately 1 week, then the rate of

release diminishes with time.

3. The chromium release increases during the first 2 weeks and levels-off during the

subsequent 2 weeks.

4. The release rates of nickel and chromium from stainless steel or nickel-titanium

arch wires are not significantly different.


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5. For both arch wire types, the release rate for nickel averaged 37 times greater than

that for chromium.

6. The estimated release rates from full-mouth orthodontic appliances are less than

10% of the reported average daily dietary intake for nickel and 0.25% of those

reported for chromium.

7. How much of these corrosive products are actually absorbed by patients

undergoing orthodontic treatment still needs to be determined.

Samir E. Bishara, Robert D. Barrett et al (1993)17 studied whether

orthodontic patients accumulate measurable concentrations of nickel in their blood

during their initial course of orthodontic therapy. Blood samples were collected at

three different time periods: before the placement of orthodontic appliances, 2 months

after their placement, and 4 to 5 months after their placement.

They arrived at the following conclusions:

1. Patients with fully banded and bonded orthodontic appliances did not show a

significant increase in the nickel blood levels during the first 4 to 5 months of

orthodontic therapy.

2. Orthodontic therapy using appliances made of alloys containing nickel-titanium did

not result in a significant increase in the blood levels of nickel.

N. Staffolani, F. Damiani, C. Lilli, M. Guerra, N.J. Staffolani, S.

Belcastro, P. Locci et al (1999)65 assayed the release of metal ions from one

orthodontic appliance which included two 304 and 316 steel molar bands, ten 316

steel brackets, one nickel–titanium archwire and a brazing alloy to connect the

elements of molar bands and brackets. The authors dipped the orthodontic appliaces


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in both inorganic (pH 3.5–6.5) and organic acid solutions (w/v 1% each of tartaric,

citric and ascorbic acid at pH 2.2 or 1.5% each of lactic and acetic acid at pH 2.5).

The release of nickel (Ni), chromium (Cr), copper (Cu), silver (Ag) and palladium

(Pd) was determined using an atomic absorption spectrophotometer.

Their results showed that the release of Ni, Cr and Cu was markedly less at pH 6.5

than at pH 3.5 at all time points in acid solution. Daily release/single appliance after

the first day decreased. Contrary to expectations, appliances immersed in organic

acid solutions at pH 2.2 or 2.5 after 28 days generally released an amount of ions

similar to that observed in inorganic acid solution at pH 3.5, with the exception of Cu.

Release of silver and palladium, two metals present in the brazing alloy, proved to be

very low (approximately 0.2 mg after 28 days).

They concluded that daily release of Ni, Cu and Cr by an orthodontic appliance in

acid pH, particularly favourable to corrosion, was well below that ingested with a

normal daily diet. They also concluded that the quantities of metal ions released in our

experimental conditions should not be cause for concern in utilising the appliance.

Neamat Abu-bakr et al (2000)66 evaluated changes in the mechanical

properties and surface texture of compomer and other materials, used in similar

clinical circumstances, when immersed in various media. The purpose of their study

was to evaluate the effect of alcoholic and low pH soft drinks on the

compressive strength, surface microhardness, solubility, and surface texture of the

compomer.

The results showed that the average compressive strength and Vickers surface

hardness showed a significant difference between materials. Results showed an

overall increase in the solubility of specimens immersed in low pH soft drinks.


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They concluded that there was a difference in the mechanical properties and surface

texture of the materials tested in this study when they were immersed in various

media.

Mockers, Deroze and Camps et al (2002)67 studied the cytotoxicity of

orthodontic bands, brackets and archwires invitro.They concluded that the orthodontic

bands, brackets and archwires were considered as non-cytotoxic.

Theodore Eliades et al (2002)68 addressed the critical issues of corrosion

potential and nickel leaching from alloys by investigating the effect of intraoral

conditions on the surface reactivity of the materials. After an overview of

fundamentals of metallurgical structure of orthodontic alloys, authors provided an

analysis of corrosion processes occurring in vivo. The recent evidence suggests that

the formation of a proteinaceous biofilm on retrieved orthodontic materials that later

undergoes calcification. Authors illustrated the vastly irrelevant surface structure of in

vivo– vs in vitro–aged alloys and discussed the potential implications of this pattern

in the reactivity of the materials. However, for patients who have a history of

hypersensitivity, authors suggested the use of the Ni-free alloy substitutes or Ni

alternatives.

In general, the clinical manifestations of Ni hypersensitivity are easy to diagnose, and

extraoral or intraoral appliances containing Ni must be removed after the development

of dermal or mucosal signs in the form of rashes or swelling. Administration of

cortisone-based substances to counteract hypersensitivity has been shown to affect the

tooth movement process, reducing the movement rate, and this administration should

be avoided if the symptoms are not severe.


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Her-Hsiung Huang, Yu-Hui Chiu et al (2005) assayed the corrosion

resistance, in terms of ion release, of different NiTi orthodontic wires in artificial

saliva with various acidities. They concluded that the average amount of Ni ions

released per day from the tested NiTi wires in artificial saliva with various acidities,

was well below the critical concentration necessary to induce allergy and under daily

dietary intake level. According to the release amount of Ti ions, the passive film

(mainly TiO2) on NiTi wires was very protective against corrosion in the slightly

acidic artificial saliva.

Nicolas Schiff, Mickaël Boinet, Laurent Morgon, Michèle Lissac et al

(2006)69 studied the influence of fluoride in certain mouthwashes on the risk of

corrosion through galvanic coupling of orthodontic wires and brackets. Their aim was

to assess the risk of corrosion caused by galvanic coupling between wires and

brackets in different solutions: artificial saliva and fluoride mouthwashes. Two

titanium alloy wires, nickel-titanium (NiTi) and copper-nickel-titanium (CuNiTi), and

the three most commonly used brackets, titanium (Ti), iron-chromium-nickel

(FeCrNi) and cobalt-chromium (CoCr), were tested in a reference solution of

Fusayama – Meyer artificial saliva and in two commercially available fluoride (250

ppm) mouthwashes, Elmex® and Meridol®. The results indicate that NiTi wires

released the most ions in the presence of Meridol® mouthwash while Cu-NiTi wires

released the most ions in the presence of Elmex® mouthwash. Although the risks are

minimal, the clinical consequences of corrosion of orthodontic devices are quite

plausible: impaired mechanical performance can lead to unsatisfactory aesthetic

results, while Ni and Cr ions released in the organism can cause allergic reactions (


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Kusy, 2004 ). It is important to eliminate these risks. Fluoride mouthwashes are

advised in the prevention of dental caries during orthodontic treatment.

Their results suggested that mouthwashes should be prescribed according to the

orthodontic materials used. A new type of mouthwash for use during orthodontic

therapy could be an interesting development in this field.

F Amini, A Borzabadi Farahani, A Jafari, M Rabbani et al (2008)37

compared the concentration of nickel, chromium and cobalt in oral mucosa cells of

patients with and without fixed orthodontic appliances. The warm and moist condition

in the mouth offers an ideal environment for the biodegradation of metals,

consequently facilitating the release of metals ions that can cause adverse effects.

Biocompatibility is strongly related to ionic release and therefore the public may

express concern about possible leakage of metal ions from an orthodontic appliance.

Their findings indicated that there was no difference in the concentration of chromium

and cobalt in oral mucosa cells of patients with or without fixed appliances. However,

a significantly higher concentration of nickel can be found in buccal mucosa cells of

patients wearing fixed orthodontic appliances. Continued follow-up is needed to

determine the long-term significance of nickel release.

Maja Kuhta; Dubravko Pavlin; Martina Slaj et al (2009)70 examined the

effects of three different parameters—pH value, type of archwire, and length of

immersion—on release of metal ions from orthodontic appliances.

They concluded that all three observed parameters—chemical composition of the

archwire, pH value of the artificial saliva, and time of exposure to the solution—

influenced ion release. Statistically significant stimulation of ion release at lower pH,


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which is in line with the hypothesis that organic acids in dentobacterial plaque affect

the release of ions, emphasizes the major role of oral hygiene in minimizing

corrosion. The most significant release of all analyzed metal ions was measured after

the first or the second observed time period, which supports the role of oxide layers in

slowing down a corrosive process on the metal surface. Release of metal ions was

influenced by composition of the orthodontic archwire, but this was not proportional

to the content of metal in the wire. Quantities of all released ions were below toxic

levels and did not exceed the daily dietary intake. However, these levels are sufficient

to cause an allergic reaction because of the high haptenic potential of released

elements.

Marcin Mikulewicz & Katarzyna Chojnacka et al (2009)71 discussed

various approaches used to investigate biocompatibility by the analysis of metals

release by the materials of which orthodontic appliances are made. Analysis of

various biomarkers of exposure: saliva, serum, mucosa cells, or urine is used in in

vivo tests. In this work, the techniques, results, and conclusions of original papers

were compared by the implementation of the concept of a systematic review. Their

aim was to report the state-of-the-art in the research on methods used to assess

exposure to trace metals from orthodontic appliances.

They concluded that metal ions were released mostly in the initial stage of the

treatment. However, the majority of studies included 1–2 months long period and did

not reflect long-term changes nor the impact of the complete treatment, the duration

of which is several years, on the whole organism and the overall accumulation of

metals from orthodontic appliances. In studies which evaluated nickel concentrations

in blood and urine, long-term metal release was detected and significant differences


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were found. It leads to the conclusion that nickel ions are released from orthodontic

appliances in measurable amounts to human organism.

TP Chaturvedi, SN Upadhayay et al (2010)72 concluded that a primary

requisite of any alloy metal used in the mouth is that it must not produce corrosion

products that will be harmful to body. In spite of recent innovative metallurgical and

technological advances and remarkable progress related to orthodontic materials,

failures do occur. One of the reasons for these failures could be corrosion (material

degradation) of orthodontic appliances. It causes severe and catastrophic

disintegration of the metal body. Corrosion (material degradation) attack may be

extremely localized and causes rapid mechanical failure of a structure, even though

the actual volume loss of material is quite small. Surface roughening and deposit build

up may have adverse effects on the efficiency of relative wire/bracket function in

orthodontic treatment. Application of fluoride containing gel/toothpaste may affect

efficiency of orthodontic appliances. In future nickel free materials should be

expected in use.

Future research is needed regarding material composition influencing corrosion,

manufacturing of metallic brackets, influence of various diet pattern as well as diet

substance on corrosion, use of topical fluoride treatment during orthodontic treatment

for oral hygiene maintenance.

Antonio Jose Ortiz, Esther Fernandez, Ascension Vicente et al

(2011)73 determined the amounts of metallic ions that stainless steel, nickel free, and

titanium alloys release to a culture medium, and evaluated the cellular viability and

DNA damage of cultivated human fibroblasts with those mediums.


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They concluded that tubes and brackets made of the 3 alloys used, released metal ions

into a standard culture medium. Those from stainless steel had greater toxicity to

cultured human fibroblasts, measured as cell viability or as Comet olive moment, than

those from nickel-free and titanium alloys, in that order. The titanium brackets and

tubes are the most biocompatible of the 3 alloys studied.

Hend Salah Hafez, Essam Mohamed Nassef Selim et al (2011) tested the

biocompatibility (cytotoxic and genotoxic effects on human tissues) of fixed

orthodontic appliances, with 3 distinct hypotheses:

(1) Fixed orthodontic appliances do not have a toxic effect,

(2) Fixed orthodontic appliances do not have an effect on the cellular metal content in

buccal mucosa cell samples,

(3) There is no difference between the effects of the various materials of fixed

orthodontic appliances.

They concluded that Fixed orthodontic appliances decreased cellular viability,

induced DNA damage, and increased the nickel and chromium contents of the buccal

mucosa cells.

Marcin Mikulewicz & Paulina Wołowiec et al (2014)52 evaluated metal

ion accumulation in hair of patients undergoing orthodontic treatment with fixed

appliances in time.

They concluded that the kinetics of metal ions released from orthodontic appliance

and their transfer to hair tissue can be evaluated by a biomarker of chronic exposure,

which is hair mineral analysis. The outcomes of the present study revealed that the

content of Cr was statistically significantly higher during the treatment than before the


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beginning of therapy. However, the doses of released metal ions did not pose a

toxicological danger.

R. S. Senkutvan, Sanjay Jacob , Anila Charles et al (2014)74 analyzed

and evaluated the rate of Ni ion release from different types arch wires used in

orthodontics.

They concluded that the release of Ni was very much below with the average dietary

intake of Ni which was not capable of causing any toxic effects. The Ni release

reached a maximum after approximately 1 week, and then the rate of release

diminishes with time. The estimated release rates from full‑mouth orthodontic

appliances are less than 10% of the reported average daily dietary intake for Ni and

how much of these corrosive products are actually absorbed by patients undergoing

orthodontic treatment still needs to be determined. The ingested amount of Ni

released from orthodontic appliances cannot be quantified using the currently

available release data, but it is well below the daily dietary intake levels.

Fariborz Amini & Mobina Mollaei et al (2014)75 evaluated comparatively

the hair nickel and chromium concentrations in fixed orthodontic patients in a

prospective design.

Authors concluded that hair nickel and chromium levels might increase after 6 months

of treatment with fixed orthodontic appliances. Gender and age influence neither the

baseline nickel or chromium values nor their time-dependent alterations.


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Fariborz Amini, Mahsa Shariati et al (2016)76 evaluated the baseline and

during-treatment nickel and chromium levels in the GCF of fixed orthodontic patients.

As an additional finding, the gingival index was also evaluated.

They concluded that nickel and chromium concentrations in GCF might increase

considerably after 1 month and 6 months of treatment with fixed orthodontic

appliances. Gingival conditions might worsen in the initial 6 months of orthodontic

treatment.

R Vinoth Kumar, N Rajvikram et al (2016)77 evaluated the release of nickel

and chromium ions in human saliva during fixed orthodontic therapy. Their results

showed that levels of nickel and chromium were statistically significant, while nickel

showed a gradual increase in the first 10 days and a decline thereafter. Chromium

showed a gradual increase and was statistically significant on the 30th day.

They concluded that there was greatest release of ions during the first 10 days and a

gradual decline thereafter. Control group had traces of nickel and chromium. While

comparing levels of nickel in saliva, there was a significant rise from baseline to 10th

and 30th-day sample, which was statistically significant. While comparing 10th day to

that of 30th day, there was no statistical significance. The levels of chromium ion in

the saliva were more in 30th day, and when comparing 10th-day sample with 30th day,

there was statistical significance. Nickel and chromium levels were well within the

permissible levels. However, some hypersensitive individuals may be allergic to this

minimal permissible level.


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STUDIES RELATED TO Ni ALLERGY AND HYPERSENSITIVITY

Bertil Magnusson, Maud Bergman et al (1982)78 investigated if patients

with known nickel allergy react to dental alloys containing various amounts of nickel

after exposure to test pieces of the alloys applied on the skin. Nickel is one of the

most common metallic contact sensitizers. Of patients with eczema 6.7-11.0% were

found to have positive patch test reactions to nickel. The reactions were found three to

five times more often in women than in men.

Contact dermatitis from nickel-containing objects is usually recognized by the

patients themselves and such objects are consequently avoided. There are, however, a

great number of objects containing nickel in our environment which are not avoided

by nickel sensitive patients because the content of the alloys are decreased. Unknown

exposure to nickel is virtually inescapable. Once nickel hypersensitivity has occurred,

it will remain. The classical clinical patterns of nickel eczema with onset under

suspenders, cheap jewellery in form of necklaces, bracelets, earrings, rings,

wristwatches and other similar objects have changed to some extent with the change

in fashion. The onset of the eczema may occur in several different locations and can

be uncharacteristic (atypical) in its clinical picture.

Luis Blanco-Dalmau et al (1984)79 concluded that a standardized patch test

should be performed on every patient who is to be treated with a prosthesis that

contains nickel to detect nickel sensitivity. A patch test should also be performed on

industrial workers or employees who may be exposed to nickel.


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Lilian Staerkjaer and Torkil Menne et al (1990)80 investigated whether

nickel sensitive persons are at greater risk of developing discomfort in the oral cavity

during orthodontic treatment.

Allergy to nickel is a cell-mediated type IV allergy. Once hypersensitivity has been

established, all dermal and mucosal surfaces are usually involved. It is stated that oral

antigenic contacts in non-sensitized individuals may induce tolerance rather than

sensitization. In a guinea-pig model Vreeburg et al. (1984) demonstrated that a fixed

occlusal splint containing 80.5 per cent nickel and 11.4 per cent chromium could

induce a state of tolerance to these metals in non-sensitized guinea-pigs. Vander Burg

et al. (1986) examined junior hairdressers and junior nurses for nickel allergy. The

examination of the junior nurses showed that those who had a history of previous

orthodontic treatment revealed a lower prevalence of nickel sensitivity (P<0.05) than

those junior nurses who had no history of orthodontic treatment. This might indicate

that the orthodontic treatment had induced tolerance. No such effect of orthodontic

treatment was observed in the junior hairdressers, who revealed a higher prevalence

of nickel sensitivity. This may be due to heavier exposure to the allergen at an early

age, a conclusion which is supported by the lower age at which the junior hairdressers

had their ears pierced.

Authors concluded that out of 1085 girls treated by intraoral orthodontic appliances

did not reveal any instance of intraoral nickel allergic reaction. On the contrary, some

studies indicate that orthodontic appliances may induce tolerance leading to a lower

incidence of nickel sensitivity.


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Justin K. Bass, Howard Fine, George J. Cisneros et al (1993)81

determined the prevalence of nickel sensitivity in a sample of orthodontic patients

before treatment and determined if standard orthodontic therapy can sensitize patients

to nickel. They also assessed gingival response to nickel-containing orthodontic

appliances in patients who are nickel sensitive before treatment.

Authors concluded that :

• The prevalence of nickel allergy is higher in females than males. (28% in

females, 0% in males.)

• Nickel-containing orthodontic appliances had little or no effect on the gingiva

and oral health of the patient.

• Orthodontic treatment may induce nickel sensitivity.

J. D. Bumgardner, J. Doeller, L. C. Lucas et al (1995)82 concluded that

the metal ions released from the nickel-chromium alloys investigated impaired

cellular energy metabolism. Furthermore, larger decreases in energy metabolism were

associated with the preferential release of nickel and beryllium ions from the

beryllium containing alloys. However, alterations in cellular energy metabolism by

the alloys were not sufficient to lead to alterations in cellular morphology,

ultrastructural organization, or viability within the time constraints of these cell

culture tests. Nevertheless, the impairment of energy metabolism was associated with

decreased functional capability of the cells. Reductions in cellular function due to

metal ions released from these alloys, especially the beryllium containing alloys, raise

concerns over the maintenance of the health of the oral tissues.

Nickel-chromium alloys completely inhibited G-6-PDH activity of the cultured cells.

It was also reported that metal ions from nickel- and chromium containing alloys


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inhibited G-6-PDH enzyme activity of macrophages. Nickel-chromium alloys also

caused reductions in intracellular ATP levels as compared to controls. However, these

reductions, which were not <20% of controls, were not significant enough to alter

cellular morphologies or viabilities. These results correspond to previous

investigations in which metal ions released from nickel-chromium alloys did not

affect the viabilities or morphologies of cultured.

Their results indicated that the types of metal ions released from nickel-chromium

dental alloys affect the functional capability of cells at levels below those necessary to

alter cellular viability and samples. The fact that corrosion products released from

these alloys inhibited metabolic enzyme activity, and caused decreases in both cellular

ATP and proliferation were at much lower levels than levels of individual metal salt

solutions required to inhibit similar cellular processes, strongly suggests a negative

synergistic effect of released metal ions on cellular metabolism. Indeed, larger

reductions in both cellular ATP levels and proliferation were observed for beryllium-

containing alloys. These alloys have been shown to referentially release nickel and

beryllium ions.

Heidi Kerosuo, Arja Kullaa et al (1996)83 investigated the frequency of

nickel hypersensitivity in adolescents in relation to sex, onset, duration and type of

orthodontic treatment, and the age at which ears were pierced. Authors confirmed that

nickel sensitization is more common in females than in males. Also, consistent with

previous reports, the results indicated the strong positive correlation between ear

piercing and nickel sensitivity in girls.

The concern of sensitizing patients to nickel through orthodontic treatment was not

supported by this study. Orthodontic treatment as such did not seem to increase the


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prevalence of nickel hypersensitivity of the adolescents. Oral contacts by nickel

containing fixed orthodontic appliances, before events that may cause sensitization to

nickel (ear piercing) may have decreased the prevalence of nickel sensitization on the

adolescents.

They concluded that orthodontic treatment does not increase the risk for nickel

hypersensitivity. Rather, these results seem to suggest that orthodontic treatment with

metallic appliances before sensitization to nickel (ear piercing) may even reduce

nickel hypersensitivity. This possible clinical benefit might be of some relevance in

planning the timing of ear piercing and orthodontic treatment.

Gabriele Schuster, Ralf Reichle, Radha Ranei Bauer et al (2004)84

conducted a survey among orthodontists in the German state of Hesse, as the

orthodontic literature is largely confined to observations of single cases, meaning that

no reliable figures on the occurrence of allergic reactions in orthodontic offices are

available. The allergic potential of orthodontic appliances is overestimated in general.

Their results revealed that after extrapolation, probably less than 0.2% of patients

exhibit an allergic skin reaction in the course of their orthodontic therapy.

The clinical relevance of nickel ions released from orthodontic materials is generally

considered to be low. It is even suggested an early treatment onset might lead to a

physical reaction in terms of desensitization through the materials used. What is

important is that the intraoral stimulus (orthodontic appliance) should occur before the

extraoral stimulus (costume jewelry, wristwatch, earrings, etc.). It is often difficult to

distinguish an irritation or a toxic eczema from an allergic reaction.

Any changes to the skin should therefore be examined by a dermatologist. A

suspected contact allergy has to be confirmed by a skin patch test. Larger scale studies


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using skin patch tests are needed to provide more exact data on the allergic potential

of orthodontic treatment.

In order to minimize the possibility of an allergic contact reaction, corrosion-resistant

materials should be used as a matter of principle. For this reason (laser) welding is

preferable to soldering, and the recycling of brackets and bands is obsolete in all

events. Gold plating or other coatings (titanium nitride) of brackets, bands and

archwires should be avoided in general.

By paying careful attention to the case history, the orthodontist can avoid using

nickel-containing materials in patients known to have a nickel allergy and can use

ceramic, plastic or titanium brackets instead for fixed appliance therapy.

In appropriate cases, titanium molybdenum alloys or fiberglass-reinforced plastics can

be used as archwire materials. A metal/skin contact through extraoral

devices can be avoided by applying an adhesive tape, Teflon®, or synthetic (e.g. nail

polish) coating or by using polyethylene tubes.

For removable appliance therapy, nickel-reduced wires have stood the test in practice.

Alternatively flexible devices in terms of silicone elastomer positioners can be used in

appropriate cases.

Marisa Cristina Leite Santos Genelhu, Marcelo Marigo et al(2005)85

assessed the roles of age, sex, previous allergic history, and time of exposure in the

NiACS (nickel-induced allergic contact stomatitis), etiopathogeny induced by fixed

orthodontic appliances.

Some oral clinical manifestations in orthodontic patients, such as gingival

hyperplasia, labial desquamation, angular cheilitis, multiform erythema, and


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periodontitis might be associated with an inflammatory response induced by the

corrosion of orthodontic appliances and the subsequent release of nickel.

This inflammatory response, from an immunologic standpoint, is considered type IV

hypersensitivity. It is manifested as nickel allergic contact stomatitis (NiACS), and its

etiology and diagnosis are difficult to establish.

In its initial phase, clinical lesions have diverse features depending on the

concentration and intensity of the exposure, the presence of local barriers, and the

area affected. A burning sensation is the most frequent symptom. The aspect of the

affected mucosa is also variable, from slight erythema to shiny lesions with or without

edema. Vesicles are rarely observed, but, when they are present, they quickly rupture,

forming erosion areas.

In chronic cases, the affected mucosa is typically in contact with the causal agent and

appears erythematous or hyperkeratotic to ulcerated. Other symptoms can also be

present, such as perioral dermatitis and, rarely, orolingual paresthesia.

Authors concluded that a detailed history, with special attention to previous allergic

reactions, is the main prognostic factor to avoid NiACS manifestations during

orthodontic therapy.

Kristen K. Volkman, Michael J. Inda et al (2007)86 characterized

the relationship between Nickel allergy and many orthodontic appliances using a

survey of practicing orthodontists in Wisconsin.

The most common manifestation of nickel allergy is allergic contact dermatitis

(ACD), a type IV T-cell–mediated delayed-type hypersensitivity reaction. Allergic

contact dermatitis occurs in areas where skin contacts nickel-containing objects such

as costume jewelry, snaps on clothing, eyeglasses, and watches. Occupational and


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industrial arenas also can be a source of nickel exposure. Allergic contact urticaria to

nickel has been reported. Nickel allergy is more common in women by two- to six

fold, presumably because of ear piercing being the sensitizing event where intimate

contact between nickel plated earrings and injured skin occurs. Use of nickel plated

earrings in combination with other irritants such as moisture or shampoo could

potentiate sensitization. Nickel allergy is more common in younger patients and in

those who are nonatopic.

The authors concluded that adverse reactions to many orthodontic appliances in

patients with nickel allergy have been observed but are uncommon. Using suitable

alternatives, patients usually can be accommodated.

J. Noble, S. I.Ahing, N. E. Karaiskos et al (2008)87 in their paper provided

a summary of nickel allergy, its epidemiology, diagnosis and recommendations and

alternatives to treatment.

IMMUNE RESPONSE: The response by the immune system to nickel is usually a

Type IV cell mediated delayed hypersensitivity also called an allergic contact

dermatitis. It is mediated by T-cells and monocytes/macrophages rather than

antibodies and consists of two phases. The first phase, or sensitisation, occurs when

nickel initially enters the body. There is usually no response present at this time but

the immune system is primed or sensitised for an allergic response. The major

sensitisation routes are nickel-containing jewellery and foods. Foods that are high in

nickel include chocolate, soyabeans, nuts and oatmeal. A response, or the elicitation

phase, is in the form of a contact mucositis or dermatitis that occurs during re-

exposure to nickel and develops over a period of days or rarely up to three weeks. If


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nickel is leached from orthodontic appliances, this Type IV hypersensitivity reaction

can occur.

They concluded that, though an allergic response to nickel in the oral mucosa from

nickel containing orthodontic appliances is more infrequent than from nickel contact

on the epidermis, it can occur, particularly in females. If nickel-related intraoral

clinical signs and symptoms appear, the orthodontist should be prepared to undertake

or continue treatment without the use of Ni-Ti wires and even without stainless steel.

The frequency of orthodontic treatment and the common use of nickel containing

orthodontic materials raises the interesting question of whether orthodontic treatment

may act to increase or decrease the burden of nickel hypersensitivity in the

population. There is evidence that oral exposure to nickel may induce immunologic

tolerance to nickel and thereby reduce the incidence of nickel to nickel

hypersensitivity are distressing to patients there are many choices of materials

available to the orthodontist as alternatives.

Olga Elpis Kolokitha, Evangelia Chatzistavrou et al (2009)88 presented

a case report of an severe reaction to nickel-containing orthodontic appliances in an

adult female patient, which occurred after the surgical exposure of her impacted teeth.

The patient had no previous history of allergy and had been wearing fixed metal upper

appliances while in orthodontic treatment to assist the eruption of her impacted teeth.

The adverse hypersensitivity reactions appeared only after the surgical exposure and

included severe signs of eczematic and urticarial reactions of the face with redness,

irritation, itching, eczema, soreness, fissuring, and desquamation as well as intraoral

diffuse red zones. Diagnostic patch testing performed by the allergist revealed


36 | P a g e

sensitization to nickel. The use of nickel-free brackets and archwires enabled the

authors to achieve the treatment goal and the patient’s satisfaction.

Ronny Fors, Berndt Stenberg et al (2012)89 investigated the association

between nickel sensitization and exposure to orthodontic appliances and piercings.

Authors gave the following conclusions:

• There was no increase in the risk of sensitizing adolescents to nickel by the

use of oral orthodontic appliances.

• When orthodontic appliance use preceded exposure to piercing, there was a

reduced risk of nickel sensitivity.

• There was a reduced risk with the use of full fixed appliances with an assumed

high release of nickel as compared with appliances including alloys with a

lower nickel release. The risk reduction was most prominent when the

duration of orthodontic treatment (before piercing) was 1–2.5 years.

• These results should thus reduce parental and patient concerns about

sensitization from orthodontic appliances.

The results support the concept of induction of immunological tolerance via

oral administration of nickel.

Lina Gölz, Spyridon N. Papageorgiou, Andreas Jäger et al (2015)90

assessed the existing evidence and investigated whether the prevalence of nickel

hypersensitivity, as assessed with nickel patch tests, is affected by orthodontic

treatment. As a secondary objective, the influence of orthodontic treatment was

adjusted, if possible, for other known confounding factors that might influence nickel

hypersensitivity. Unrestricted electronic and manual searches were performed until


37 | P a g e

July 2013 for human clinical studies assessing orthodontic treatment and nickel

hypersensitivity.

Authors concluded that according to the existing evidence, they could not show that

orthodontic treatment influences the prevalence of nickel hypersensitivity.

However, there was evidence of confounding by various influencing factors, such as

patient sex, piercings, or allergic history, which could not be removed, owing to

incomplete data.

The existing evidence indicated that there was a significantly lower risk of nickel

hypersensitivity when orthodontic treatment preceded piercing than when orthodontic

treatment occurred after piercing. This protective role of orthodontic treatment against

nickel allergy was robust to possible confounding. This might, in part, be explained

by orally induced tolerance via nickel ions released during orthodontic treatment.

Materials and Method

38 | P a g e

MATERIALS AND METHOD

MATERIALS:

Fixed orthodontic appliance components:

• Orthodontic archwires : Nickel-titanium archwires and Stainless

steel archwires (BROOKLYN ORTHODONTICS, USA)(Figure 1)

• Heat activated nickel titanium archwires (AMERICAN

BRACESTM) (Figure-2)

• Brackets (“0.022”-inch slot stainless steel MBT prescription

(OrthoxTM) (Figure-3)

• Stainless steel bands (SLR-WELCARE ORTHODONTICS)-

(Figure-4)

• Buccal tubes (Figure-5)

• Lingual attachments (Figure-6)

Glass containers (Figure-7)

Glass tubes with wooden cork (Figure-8)

Tweezer (Figure-9)

PRODUCTS:

Saliva substitute : SALEVA-DENT AIDS (Figure-10)

Each bottle of Saleva-Dent Aids contains:

• Purified water

• Sodium Phosphate

• Sodium chloride


39 | P a g e

• Potassium chloride

• Sodium Saccharine

• Sodium carboxymethyl cellulose

• Colour – Brilliant blue FCF

30 Different dietary samples

METHODOLOGY:

Type of study:

Cross sectional study (In-vitro)

Procedure Protocol

• 100 ml of saliva substitute placed in 30 different containers labelled with

each respective dietary sample name.

• Fixed orthodontic appliances comprised of brackets, bands, buccal tubes,

lingual attachments, archwires were placed in each container.

• Each day the fixed orthodontic components were immersed in the

respective dietary samples four times daily for two minutes and then

placed back at the respective glass containers containing artificial saliva.

• This procedure is repeated daily for 90 days.

• The sample of artificial saliva (20ml) from the glass container is taken into

glass tubes with the help of pipette and the glass tubes are sealed with

wooden cork.

• The samples are tested using Inductive coupled plasma mass spectrometer

(ICP-MS) at three different time periods (1 week , 1 month and 3 months)


40 | P a g e

HUMAN SUBJECTS’ PROTECTION: Not applicable

RISKS: Not applicable

PATIENT PROTECTION: Not applicable

FUNDING

• Self-funding by the Principle investigator

• Monetary compensation: Nil

CONFIDENTIALITY: Not applicable

INFORMED CONSENT: Not applicable

Color plates

41 | P a g e

Figure 1: Orthodontic archwires : Ni-Ti archwires and SS archwires (BROOKLYN

ORTHODONTICS)

Figure 2: Heat activated nickel titanium archwires (AMERICAN BRACES)

Color plates

42 | P a g e

Figure 3: Brackets (“0.022”-inch slot stainless steel MBT prescription (Orthox )

Figure 4: Stainless steel bands (SLR-WELCARE ORTHODONTICS)

Color plates

43 | P a g e

Figure 5: Lingual attachments

Figure 6: Buccal tubes

Color plates

44 | P a g e

Figure 7: Glass container with wooden cork

Figure 8: Tweezer

Color plates

45 | P a g e

Figure 9: Glass container

Figure 10: Saliva substitute : SALEVA-DENT AIDS

Results

46 | P a g e

RESULTS

In the present study, 100 ml of saliva substitute placed in 30 different containers

labelled with each respective dietary sample name were taken and fixed

orthodontic appliances comprised of brackets, bands, buccal tubes, lingual

attachments, archwires were placed in each container. Each day the fixed

orthodontic components were immersed in the respective dietary samples four

times daily for two minutes and then placed back at the respective glass containers

containing artificial saliva. This procedure is repeated daily for 90 days. The

sample of saliva substitute (20ml) from the glass container is taken into glass

tubes with the help of pipette and the glass tubes are sealed with wooden cork.

The samples were tested at three different time periods (1 week, 1 month and 3

months)

The results were evaluated and tested for nickel leach from the fixed orthodontic

components into the salivary substitute at three different time intervals. (1 week, 1

month and 3 months)

STATISTICAL ANALYSIS:

Statistical analysis was done by IBM SPSS (IBM Corp. Released 2011.

IBM SPSS Statistics for Windows, Version 20.0. Armonk, NY: IBM Corp.)

Table 1: Baseline nickel content present in saliva substitute.

S.NO. SALIVA SUBSTITUTE BASELINE NICKEL CONTENT

A SALEVATM 0.23 mg/L

Results

47 | P a g e

Table 2: Amount of nickel leach from fixed orthodontic components into the

Saliva substitute from different dietary components in three different time

interval

S.NO. DIETARY COMPONENT

T1

(mg/L)

1 WEEK

T2

(mg/L)

1 MONTH

T3

(mg/L)

3 MONTHS

1. LEMON JUICE 0.63 1.13 2.78

2. PEPSI 0.75 1.32 2.98

3. COCA COLA 0.79 1.01 2.95

4. SPRITE 0.70 0.94 2.69

5. BOVONTO 0.68 0.88 2.70

6. 7UP 0.71 0.97 2.75

7. FANTA 0.66 0.90 2.55

8. MIRINDA 0.68 0.87 2.49

9. THUMBS UP 0.78 1.06 2.77

10. MOUNTAIN DEW 0.72 0.98 2.68

11. RED BULL 0.73 1.11 2.91

12. MONSTER 0.70 0.99 2.80

13. GATORIDE 0.67 0.88 2.45

14. VINEGAR 0.57 1.11 2.91

15. TEA 0.38 0.66 1.36

16. COFFEE 0.41 0.69 1.50

17. CURD 0.71 0.98 2.85

18. SAMBHAR 0.31 0.60 1.08

19. RASAM 0.30 0.58 0.98

20. ORANGE JUICE 0.61 0.96 2.08

21. APPLE JUICE 0.70 0.81 1.66

22. APPY FIZZ 0.69 1.01 1.78

23. POMEGRANATE JUICE 0.60 0.89 1.44

24. TROPICANA 0.58 0.78 1.32

25. MINUTE MAID 0.55 0.69 1.02

26. MAZZA 0.52 0.68 1.22

27. GRAPE JUICE 0.68 0.93 2.01

28. FROOTI 0.55 0.62 1.30

29. LEMON TEA 0.68 0.99 1.98

30. MILK 0.51 0.90 1.87

Results

48 | P a g e

Table 3: Amount of nickel leach from fixed orthodontic components into the

Saliva substitute from different dietary components in three different time

interval after deducting the baseline nickel content from saliva substitute.

S.NO. DIETARY COMPONENT

T1

(mg/L)

1 WEEK

T2

(mg/L)

1 MONTH

T3

(mg/L)

3 MONTHS

1. LEMON JUICE 0.4 0.9 2.55

2. PEPSI 0.52 1.09 2.75

3. COCA COLA 0.56 0.78 2.72

4. SPRITE 0.47 0.71 2.46

5. BOVONTO 0.45 0.65 2.47

6. 7UP 0.48 0.74 2.52

7. FANTA 0.43 0.67 2.32

8. MIRINDA 0.45 0.64 2.26

9. THUMBS UP 0.55 0.83 2.54

10. MOUNTAIN DEW 0.49 0.75 2.45

11. RED BULL 0.5 0.88 2.68

12. MONSTER 0.47 0.76 2.57

13. GATORIDE 0.44 0.65 2.22

14. VINEGAR 0.34 0.88 2.68

15. TEA 0.15 0.43 1.13

16. COFFEE 0.18 0.46 1.27

17. CURD 0.48 0.75 2.62

18. SAMBHAR 0.08 0.37 0.85

19. RASAM 0.07 0.35 0.75

20. ORANGE JUICE 0.38 0.73 1.85

21. APPLE JUICE 0.47 0.58 1.43

22. APPY FIZZ 0.46 0.78 1.55

23. POMEGRANATE JUICE 0.37 0.66 1.21

24. TROPICANA 0.35 0.55 1.09

25. MINUTE MAID 0.32 0.46 0.79

26. MAZZA 0.29 0.45 0.99

27. GRAPE JUICE 0.45 0.7 1.78

28. FROOTI 0.32 0.39 1.07

29. LEMON TEA 0.45 0.76 1.75

30. MILK 0.28 0.67 1.64

Results

49 | P a g e

Table 1 reveals the baseline nickel content already present in the saliva substitute

sample which was tested by Inductive coupled plasma mass spectrometer (ICP-

MS), which showed a presence of 0.23 mg/l amount of nickel content.

Table 2 gives the amount of nickel leached from 30 different dietary samples into

the saliva substitute, tested by Inductive coupled plasma mass spectrometer (ICP-

MS) at three different time intervals:

T1: At 1 week

T2: At 1 month

T3: At 3 months

Table 3 gives the exact amount of nickel leached from 30 different dietary

components into the saliva substitute after deducting the baseline nickel content

which was already present in the saliva substitute at three different time intervals.

The results revealed that at 1st week time interval, Coca Cola, Thumbs up, Pepsi

showed the highest amount of nickel leach (0.56 mg/l, 0.55mg/l, 0.52mg/l


After 1 month, the results revealed that Pepsi, Lemon juice, Red bull, Vinegar

showed the highest amount of nickel leached (1.09mg/l, 0.9mg/l, 0.88mg/l,

0.88mg/l respectively) into the saliva substitute.

3 months interval results show that Pepsi, Coca cola, Red bull, Vinegar showed

the highest amount of nickel leached (2.75mg/l, 2.72mg/l, 2.68mg/l, 2.68mg/l


Results

50 | P a g e

CHARTS

Chart-1

Chart-2

0.4

0.520.56

0.470.450.48

0.430.45

0.550.490.5

0.470.44

0.34

0.150.18

0.48

0.080.07

0.38

0.470.46

0.370.350.32

0.29

0.45

0.32

0.45

0.28

0

0.1

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0.3

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NICKEL CONTENT - T1

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0.830.75

0.88

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0.65

0.88

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0.75

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0.73

0.58

0.78

0.66

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NICKEL CONTENT - T2

Results

51 | P a g e

Chart-3

2.5

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2.7

5

2.7

2

2.4

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2.4

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2.5

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2.3

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NICKEL CONTENT - T3

Discussion

52 | P a g e

DISCUSSION

Our diet has an impact on our well-being and on our health. In recent years,

people have become more aware and concerned about maintaining good health

and having a healthy lifestyle. A good diet plays an important role in maintaining

good health.58,91 Even the governments of different countries have been working

to formalize national nutrition monitoring system, and there are new labeling laws

for foods regarding fat and salt content.92

With so much focus on healthier foods and more nutritional food choices, dietary

counseling and nutritional education relevant to oral health have become an

important component of dental education. In fact, 1987 guidelines for

accreditation of dental schools by the American dental Association require that

“the graduate must be competent to provide dietary counseling and nutritional

education relevant to oral health.” Study of diet and nutrition is also a mandatory

part of curriculum in Indian dental schools.93

The warm and moist condition in the mouth offers an ideal environment for the

biodegradation of metals, consequently facilitating the release of metals ions that

can cause adverse effects.

The marked increase of orthodontic treatment has drawn attention to potential

undesired effects. Nickel (Ni)-containing alloys are present in a substantial

number and wide variety of appliances, auxiliaries, and utilities used in

orthodontics and thus become an integral part of almost every routine orthodontic

intervention.

As contemporary orthodontics relies on various bonded attachments, arch wires,

and other devices to achieve tooth movement. The demands made on them are

Discussion

53 | P a g e

complex because they are placed under many stresses in the oral environment,

which include immersion in saliva, ingested fluids, temperature fluctuations, and

masticatory force.

The oral cavity is a complete corrosion cell, with many factors that enhance the

biodegradation of orthodontic appliances. Saliva acts as an electrolyte for electron

and ion conduction, and the fluctuation of pH and temperature, the enzymatic and

microbial activity, and the various chemicals introduced into the oral cavity

through food and drink are all corrosion conductors. The inherent heterogeneity of

each metal alloy and its use with other alloys, the microsurface discontinuity, the

forces acting on the appliances, and the friction between wires and brackets also

add to the corrosion process.

Orthodontic alloys are made from various metals, among which chromium and

nickel are of major concern. Both of these genotoxic, mutagenic, and cytotoxic

metals might induce contact allergy, asthma, hypersensitivity, birth defects, and

reproductive damage. Corrosion of orthodontic alloys might lead to release of

considerable amounts of nickel and chromium ions into saliva.

The present study aims to investigate the effect of dietary habits on the

release of Ni ions from orthodontic appliances in south Indian population.

For the study, we have selected 30 different types of dietary food items which are

commonly consumed by the south Indian population. 100 ml of saliva substitute

placed in 30 different containers labelled with each respective dietary sample

name were taken and fixed orthodontic appliances comprised of brackets, bands,

buccal tubes, lingual attachments, archwires were placed in each container. Each

Discussion

54 | P a g e

day the fixed orthodontic components were immersed in the respective dietary

samples four times daily for two minutes and then placed back at the respective

glass containers containing artificial saliva. This procedure is repeated daily for 90

days. The sample of saliva substitute (20ml) from the glass container is taken into

glass tubes with the help of pipette and the glass tubes are sealed with wooden

cork.

The samples were tested at three different time periods (1 week, 1 month and 3

months) using Inductive coupled plasma mass spectrometer (ICP-MS).

The salivary substitute (Saleva-Dent aids) was tested using ICP-MS before the

immersion of fixed orthodontic components for assessing the baseline nickel

content of the saliva substitute.

The test result showed that the saliva substitute had a nickel content of 0.23mg/l,

indicating the baseline nickel content of the solution.

Each day the fixed orthodontic components were immersed in the respective

dietary samples four times daily for two minutes and then placed back at the

respective glass containers containing saliva substitute.

After 1week interval, saliva substitute from each 30 containers were taken into

numbered glass tubes from 1 to 30, and was tested for nickel content using

Inductive coupled plasma-Mass spectrometer (ICP-MS).

The results revealed that at 1st week time interval, Coca Cola, Thumbs-up, Pepsi

showed the highest amount of nickel leach (0.56 mg/l, 0.55mg/l, 0.52mg/l


Discussion

55 | P a g e

After 1 month, the results revealed that Pepsi, Lemon juice, Red bull, Vinegar

showed the highest amount of nickel leached (1.09mg/l, 0.9mg/l, 0.88mg/l,

0.88mg/l respectively) into the saliva substitute.

3 month interval results show that Pepsi, Coca cola, Red bull, Vinegar showed the



To maintain a healthy body it is essential to follow a balanced diet. A diet is called

balanced when it comprises of all the basic nutrients that the body requires and

also meets the calorie requirements of the individual his/her age, sex, activity level

etc in mind. A well balanced diet for a typical Indian teenager is given below.

Food Group Quantity Sources

Cereals 300g Wheat, Rice, Millets

Pulses 60g (Veg), 30g (Non-

Veg)

Sprouts/Fermented

Meat 30g Egg/Chicken/Fish

Vegetables 300g (minimum) Peas, Carrot, Pumpkin,

Beans, Green Leaf

Vegetables etc.

Fruits 100g (minimum) Orange, Apple, Papaya,

Guava, Mango etc

Milk & Milk Products 300g Cheese, Curd etc

Sugar 20g Confectionary

Fats 20g Oil/Butter/Ghee

Orthodontists often advise their patients to eat soft foods during treatment to

accommodate pressure sensitivity experienced with tooth movement however

there is little literature on how orthodontic treatment affects a patient’s diet and

even little reports on clear cut diet guidelines for orthodontic patients. A nutritious

balanced diet is the last thing on the patients mind in the initial 3-4 days of

orthodontic adjustments especially when they think that with the braces

Discussion

56 | P a g e

they have very limited food choices.

Most of them are not aware that it is possible to eat more healthily with braces

because; now one has to watch what he/she is eating.

A BRACES FRIENDLY BALANCED DIET

Cereals (Carbohydrates): - This group should provide ¼ th of our total energy

requirements. The forms in which cereals are generally consumed in a typical

Indian diet consist of chapattis, rice and bread. They are generally an easy food

groups for braces wearers because most grain products are very soft and easily

chewed. In cases of discomfort dunking/mashing chapattis in curries and dals

ensure that you don’t miss out on two most vital components of a balanced diet –

carbohydrates and proteins.

Milk and milk products: - Dairy products should comprise about ¼ th of the total

dietary requirements. Strong bones and teeth rely on a diet that is rich in calcium.

Dairy products provide us with calcium, vitamin D, potassium and even protein.

Dairy products are an excellent choice for braces wearers because most dairy

products are soft and require very little chewing. Milk, milk shakes, yogurt (curd)

and cottage cheese are commonly used milk products in Indian

diets and its consumption by patients should be encouraged.

Vegetables: - Vegetables again comprise about ¼ th of the total dietary

requirements. Vegetables provide us with vitamins and minerals that are essential

for growing bodies. Most Indian diets consume vegetables in the cooked form, so

Discussion

57 | P a g e

they don’t provide much of the problem for braces wearers. They can be meshed

up further for increased comfort. Raw vegetables or salads can be grated or cut

into bite sized pieces.

Fruits: - Fruit is an essential part of a healthy diet but eating it with braces can be

quite challenging. Hard fruits like apple, unripe pears and peaches can be very

difficult to bite into because of the brackets that are on the teeth. After a wire

change even the softest food can be a nightmare. For 3-4 days after an orthodontic

appointment, choose citrus juicy fruits such as oranges and berries. Hard fruits can

be cut bite sized pieces so they can be chewed with the back teeth. If nothing else

works fruit juice is always a healthy easy option. Frequently it is uncomfortable to

bite or chew something very cold with all that metal around the teeth. Having

eatables at room temperature helps.

Nuts and Seeds: - Carefully selecting the choices from this vegetarian group will

help keep the braces secure. Nuts and seeds are very hard and they are very small

– two challenging aspects for braces wearers. During the duration of active

orthodontic treatment select nut spreads or coarsely grind your favorite nuts and

seed.

Meat: - Meat poses a problem for braces wearers because it is fibrous, making it

hard to chew. Avoid eating meat right from the bone. Tofu or cottage cheese

provides a safe alternative to meat as a source of protein. Select, lean, tender cuts

of meat and cut them into bite size pieces before you eat it.

Summary and Conclusion

58 | P a g e

SUMMARY AND CONCLUSION

SUMMARY

The present study was done in the department of orthodontics and

Dentofacial Orthopaedics, Tamil Nadu government dental college and hospital,

Chennai in collaboration with Chennai Mettex lab, Chennai. A total of 30

different types of dietary food items which are commonly consumed by the south

Indian population was selected.

100 ml of saliva substitute placed in 30 different containers labelled with each

respective dietary sample name were taken and fixed orthodontic appliances

comprised of brackets, bands, buccal tubes, lingual attachments, archwires were

placed in each container. Each day the fixed orthodontic components were

immersed in the respective dietary samples four times daily for two minutes and

then placed back at the respective glass containers containing artificial saliva. This

procedure is repeated daily for 90 days. The sample of saliva substitute (20ml)

from the glass container is taken into glass tubes with the help of pipette and the

glass tubes are sealed with wooden cork. The samples were tested at three

different time periods (1 week, 1 month and 3 months)

The results were evaluated and tested for nickel leach from the fixed orthodontic

components into the salivary substitute at three different time intervals. (1 week, 1

month and 3 months).


59 | P a g e

From the findings observed in this present study it can be concluded that

1. At 1st week time interval, Coca Cola, Thumbs-up, Pepsi showed the

highest amount of nickel leach (0.56 mg/l, 0.55mg/l, 0.52mg/l


2. After 1 month, Pepsi, Lemon juice, Red bull, Vinegar showed the highest

amount of nickel leached (1.09mg/l, 0.9mg/l, 0.88mg/l, 0.88mg/l


3. At 3 months interval, Pepsi, Coca cola, Red bull, Vinegar showed the



CONCLUSION

The results suggest that consumption of food products of low pH (such as Pepsi,

Coca cola, Red bull, Thumbs up, lemon juices and vinegar) can intensify

aggressiveness of conditions in the oral cavity and has an effect on increasing the

release of Ni from orthodontic appliances. Therefore, it would be useful to

recommend to orthodontic patients to limit consumption of foods and drinks

which are characterized by low values of pH to reduce the quantity of ions

solubilized from metal alloys.


60 | P a g e

An orthodontic appliance friendly balanced diet

FOOD GROUP MAIN NUTRIENTS

Cereals, grain products, rice and wheat

flour, maize, rice flakes, and Maida

Energy, protein, invisible fats,

Vitamins B and B2, folic acid,

iron, and fiber

Pulses ‑ Legumes, Bengal gram, black

gram, green gram, red gram, Rajmah,

soyabean

Energy, protein, invisible fats,

Vitamins B and B2, folic acid,

calcium, iron, and fiber

Milk and meat products Protein, fat, Vitamin B2, calcium

Meat and chicken liver, fish, eggs Protein, fat, and

Vitamin B2

Fruits ‑ Apple, guava, tomato ripe,

papaya, orange, sweet lime, watermelon

Fiber, Vitamin C, carotenoids

Vegetables (green leafy) Invisible fat, carotenoids,

Vitamin B2, folic acid, iron,

calcium fiber

Other vegetables- Carrot, brinjal,

Lady’s finger, capsicum, beans, onion,

cauliflower

Carotenoids, folic acid, calcium

fiber

Fat and sugar‑butter, ghee, groundnut,

coconut oil

Energy, fats, and essential fatty

acids

Sugar and jiggery Energy


61 | P a g e

BRACES‑FRIENDLY EATING TIPS

When you abide by the rules of what to eat and what not to eat when wearing

braces, you are doing yourself a favor. Your orthodontist gives you dietary

guidelines for a reason. When you are wearing braces, it is important to avoid

certain foods that can damage the orthodontic appliances, brackets, and wires,

which may cause delays in treatment.

The key rule is: Nothing hard, sticky or chewy!

Here is a handy red, yellow, and green light list of do’s and don’ts when it comes

to snacking while wearing braces.

“ABSOLUTELY NO” FOOD GROUP

Gum – sugarless or otherwise

Sticky foods – toffees, candies etc

Hard food – nuts (unless grinded), popcorn, corn on the cob, pizza crusts, ice,

cookies.

Red light (never eat!):

Nuts, popcorn, chewing gum, hard pretzels, pizza crust, Gummy Bears, caramels,

jelly beans, chocolate chips, ice cubes, chapatti, paratta, nan and boiled candy, and

foods with low ph value.


62 | P a g e

Yellow light (use caution, cut up, and chew with back teeth) :

Nacho Chips, Bagels, Ribs, chicken wings, raw vegetables, hard fruit (i.e., apples,

unless sliced thin or cut in small pieces), fruit with pits (i.e., peaches), corn on the

cob, crusty bread, Granola Bars, and foods high in sugar (e.g., pop, candy): don’t

eat often and brush soon after.

Green light (go for it!):

Ice cream (no nuts), potato chips, steamed vegetables, pasta potatoes, French fries,

soft pretzels, yogurt, pudding, jelly, soup, subs, sandwiches, cereal in milk,

cheese, eggs, milkshakes, caramel bars, and peanut butter cups.

Bibliography

63 | P a g e

BIBLIOGRAPHY

1. Burkert NT, Muckenhuber J, Grobschsdl F, Rasky E, Freidl W (2014)

Nutrition and Health – The Association between Eating Behavior and Various

Health Parameters: A Matched Sample Study. PLoS ONE 9(2): e88278.

doi:10.1371/journal.pone.0088278

2. Attin, K Weiss, K Becker, W Buchalla, A Wiegand, Impact of modified acidic

soft drinks on enamel erosion. Oral Diseases (2005)

3. SariME, Erturk AG, Koyuturk AE, Bekdemir Y (2014) Evaluationof the effect

of food and beverages on enamel and restorative materialsby SEM and Fourier

transform infrared spectroscopy. Microsc Res Tech 77:79–90

4. Marcin Mikulewicz & Katarzyna Chojnacka, Trace Metal Release from

Orthodontic Appliances by In Vivo Studies: A Systematic Literature Review.

Biol Trace Elem Res (2010) 137:127–138 DOI 10.1007/s12011-009-8576-6

5. Occurrence of risk factors fordental erosion in the population of young adults

in Norway Asmyhr, Grytten J, Holst D. Occurrence of risk factors for dental

erosion in the population of young adults in Norway. Community Dent Oral

Epidemiol2012. © 2012 John Wiley & Sons

6. Berge M, Gjerdet NR. Corrosion of silver soldered orthodontic wires. Acta

Odontol Scand 1982;40:75-9.

7. Maijer R, Smith DC. Corrosion of orthodontic bracket bases. Am J Orthod

1982;81:43-8.

8. Blanco-Dalmau L, Carrasquillo-Alberty H, Silva-Parra J (1984) A study of

nickel allergy. J Prosthet Dent 52:116–119

9. Eliades T, Pratsinis H, Kletsas D, Eliades G, Makou M (2004)

Characterization and cytotoxicity of ions released from stainless steel and

Bibliography

64 | P a g e

nickel-titanium orthodontic alloys. Am J Orthod Dentofacial Orthop 125:24–

29

10. Genelhu M, Marigo M, Alves-Oliveira LF, Malaquias L, Gomez RS (2005)

Characterization of nickelinduced allergic contact stomatitis associated with

fixed orthodontic appliances. Am J Orthod Dentofacial Orthop 128:378–381

11. Hayes RB (1997) The carcinogenicity of metals in humans. Cancer Causes

Control 8:371–385

12. Grimsdottir MR, Hensten-Pettersen A, Kulmann A. Cytotoxic effect of

orthodontic appliances. European Journal of Orthodontics 1992;14:47–53

13. Bass JK, Fine H, Cisneros GJ. Nickel hypersensitivity in the orthodontic

patient. American Journal of Orthodontics and Dentofacial Orthopedics

1993;103:280–285

14. Kerosuo H, Kullaa A, Kerosuo E, Kanerva L, Hensten-Petterson A. Nickel

allergy in adolescents in relation to orthodontic treatment and piercing of ears.

American Journal of Orthodontics and Dentofacial Orthopedics

1996;109:148–154

15. Rietschel RL, and Fowler JF Jr (Eds). Contact dermatitis and other reactions to

metals.

16. Barret RD, Bishara SE, Quinn JK. Biodegradation of orthodontic appliance.

Part I. Biodegradation of nickel and chromium in vitro. American Journal of

Orthodontics and Dentofacial Orthopedics 1993;103:243–250

17. Bishara SE, Barret RD, Selim MI. Biodegradation of orthodontic appliances.

Part II. Changes in the blood level of nickel. American Journal of

Orthodontics and Dentofacial Orthopedics 1993;103:115– 119

Bibliography

65 | P a g e

18. Mydlarski PR, Katz AM, Mamelak AJ, et al. Contact dermatitis. In

Middleton’s Allergy Principles & Practice. Adkinson N F Jr, Yunginger JW,

Busse WW, Bochner BS, Holgate ST, and Simons E R (Eds). Philadelphia:

Mosby, 1581–1597, 2003.

19. Contact urticaria. In Fisher’s Contact Dermatitis. Rietschel RL, and Fowler JF

Jr (Eds). Philadelphia: Lippincott Williams & Wilkins, 581–604, 2001.

20. In vitro yelease of nickel and chromium from simulated orthodontic

appliances H. Y. Park, D.M.D., and T. R. Shearer, Ph.D.

21. Asmyhr Q, Grytten J, Holsr D (2012) Occurrence of risk factors for dental

erosion in the population of young adults in Norway. Community Dent Oral

Epidemiol 40:425–431

22. Aghili HA, Hoseini SM, Yassaei S, Fatahi Meybodi SA, Zaeim MH,

Moghaadam MG (2014) Effects of carbonated soft drink consumption on

orthodontic tooth movements in rats. J Dent (Teheran) 11:123–130

23. Anusavice K. Phillips’ science of dental materials. 11th ed. Philadelphia: W.

B. Saunders; 2003: p. 57-64.

24. Eliades T, Bourauel C. Intraoral aging of orthodontic materials: the picture we

miss and its clinical relevance. Am J Orthod Dentofacial Orthop

2005;127:403-12.

25. Amini F, Farahani A, Jafari A, Rabbani M. In vivo study of metal content of

oral mucosa cells in patients with and without fixed orthodontic appliances.

Orthod Craniofac Res 2008;11:51-6.

26. Faccioni F, Franceschetti P, Cerpelloni M, Fracasso M. In vivo study on

metal release from fixed orthodontic appliances and DNA damage in oral

mucosa cells. Am J Orthod Dentofacial Orthop 2003; 124:687-94.

Bibliography

66 | P a g e

27. Garhammer P, Schmalz G, Hiller KA, Reitinger T. Metal content of biopsies

adjacent to dental cast alloys. Clin Oral Invest 2003;7:92-7.

28. Brantley WA, Eliades T (2001) Orthodontic materials: scientific and clinical

aspects. Georg Thieme, Stuttgart, pp 271–286

29. House K, Sernetz F, Dymock D, Sandy JR, Ireland AJ (2008)Corrosion of

orthodontic appliances—should we care? Am J Orthod Dentofac Orthop

133:584–592

30. Faccioni F, Franceschetti P, Cerpelloni M, Fracasso ME (2003) In vivo study

on metal release from fixed orthodontic appliances and DNA damage in oral

mucosa cells. Am J Orthod Dentofac Orthop 124:687–693

31. Mikulewicz M, Chojnacka K (2010) Trace metal release from orthodontic

appliances by in vivo studies: a systematic literature review. Biol Trace Elem

Res 137:127–138

32. Hafez HS, Selim EM, Kamel Eid FH, Tawfik WA, Al-Ashkar EA, Mostafa

YA (2011) Cytotoxicity, genotoxicity, and metal release in patients with fixed

orthodontic appliances: a longitudinal in-vivo study. Am J Orthod Dentofac

Orthop 140:298–308

33. Amini F, Rakhshan V, Mesgarzadeh N (2012) Effects of long-term fixed

orthodontic treatment on salivary nickel and chromiumlevels: a 1-year

prospective cohort study. Biol Trace Elem Res 150:15–20

34. Amini F, Rakhshan V, Sadeghi P (2012) Effect of fixed orthodontic therapy

on urinary nickel levels: a long-term retrospective cohort study. Biol Trace

Elem Res 150:31–36

35. Amini F, Harandi S, Mollaei M, Rakhshan V (2015) Effects of fixed

orthodontic treatment using conventional versus metal injection molding

Bibliography

67 | P a g e

(MIM) brackets on salivary nickel and chromium levels: a double-blind

randomized clinical trial. Eur J Orthod. doi:10.1093/ ejo/cju079

36. Amini F, Rahimi H, Morad G, Mollaei M (2013) The effect of stress on

salivary metal ion content in orthodontic patients. Biol Trace Elem Res

155:339–343

37. Amini F, Borzabadi Farahani A, Jafari A, Rabbani M (2008) In vivo study

ofmetal content of oralmucosa cells in patients with and without fixed

orthodontic appliances. Orthod Craniofacial Res 11:51–56

38. Matos de Souza R, Macedo de Menezes L (2008) Nickel, chromium and iron

levels in the saliva of patients with simulated fixed orthodontic appliances.

Angle Orthod 78:345–350

39. Amini F, Jafari A, Amini P, Sepasi S (2012) Metal ion release from fixed

orthodontic appliances—an in vivo study. Eur J Orthod 34: 126–130

40. Eliades T, Athanasiou AE (2002) In vivo aging of orthodontic alloys:

implications for corrosion potential, nickel release, and biocompatibility.

Angle Orthod 72:222–237

41. Hwang CJ, Shin JS, Cha JY (2001) Metal release from simulated fixed

orthodontic appliances. Am J Orthod Dentofac Orthop 120: 383–391

42. Kocadereli L, Atac PA, Kale PS, Ozer D (2000) Salivary nickel and chromium

in patients with fixed orthodontic appliances. Angle Orthod 70:431–434

43. Agaoglu G, Arun T, Izgi B, Yarat A (2001) Nickel and chromium levels in the

saliva and serum of patients with fixed orthodontic appliances. Angle Orthod

71:375–379

44. Natarajan M, Padmanabhan S, Chitharanjan A, Narasimhan M (2011)

Evaluation of the genotoxic effects of fixed appliances on oral mucosal cells

Bibliography

68 | P a g e

and the relationship to nickel and chromium concentrations: an in-vivo study.

Am J Orthod Dentofac Orthop 140:383–388

45. Kusy RP (2004) Clinical response to allergies in patients. Am J Orthod

Dentofac Orthop 125:544–547

46. Li Z, Gu JY, Wang XW, Fan QH, Geng YX, Jiao ZX, Hou YP, Wu WS

(2010) Effects of cadmium on absorption, excretion, and distribution of nickel

in rats. Biol Trace Elem Res 135:211–219

47. Abtahi M, Jahanbin A, Yaghoubi M, Esmaily H, Zare H (2013) Are more

nickel ions accumulated in the hair of fixed orthodontic patients? Indian J

Dent Res 24:298–301

48. Martin-Camean A, Molina-Villalba I, Jos A, Iglesias-Linares A, Solano E,

Camean AM, Gil F (2014) Biomonitorization of chromium, copper, iron,

manganese and nickel in scalp hair from orthodontic patients by atomic

absorption spectrometry. Environ Toxicol Pharmacol 37:759–771

49. Menezes LM, Quintao CA, Bolognese AM(2007) Urinary excretion levels of

nickel in orthodontic patients. Am J Orthod Dentofac Orthop 131:635–638

50. Levrini L, Lusvardi G, Gentile D (2006) Nickel ions release in patients with

fixed orthodontic appliances. Minerva Stomatol 55: 115–121

51. Mikulewicz M, Wolowiec P, Loster B, Chojnacka K (2014) Metal ions

released from fixed orthodontic appliance affect hair mineral content. Biol

Trace Elem Res

52. Kusy RP (2002) Orthodontic biomaterials: from the past to the present. Angle

Orthod 72:501–512.

53. Hafez HS, Selim EMN, Eid FHK, Tawfik WA, Al-Ashkar EA, Mostafa YA

(2011) Cytotoxicity, genotoxicity, and metal release in patients with fixed

Bibliography

69 | P a g e

orthodontic appliances: a longitudinal in-vivo study. Am J Orthod Dentofacial

Orthop 140:298–308

54. Wataha J. Biocompatibility of dental casting alloys: a review. J Prosthet Dent

2000;83:223-34.

55. Rojas E, Herrera L, Poirier L, Ostrosky-Wegman P. Are metals dietary

carcinogens? Mutat Res 1999;443:157-81.

56. Schmalz G, Garhammer P. Biological interactions of dental cast alloys with

oral tissues. Dent Mater 2002;18:396-406.

57. Khatri JM, Kolhe VD. Nutrition and orthodontics.Int J Orthod Rehabil

2018;9:163-7.

58. R Sharma, S Mittal, A Singla, M Virdi. Nutritional Guidelines for Orthodontic

Patients. The Internet Journal of Nutrition and Wellness. 2009 Volume 10

Number 2.

59. Stephen F. Litton, Orthodontic tooth movement during an ascorbic acid

deficiency. Am J Orthod March 1974.

60. C. Abalos, A. Paul, A. Mendoza, E. Solano, C. Palazon, and F.J. Gil. Influence

of Soft Drinks with Low pH on Different Ni-Ti Orthodontic Archwire Surface

Patterns. Journal of Materials Engineering and Performance Volume 22(3)

March 2013—759

61. H. Y. Park, and T. R. Shearer, In vitro yelease of nickel and chromium from

simulated orthodontic appliances. Am J Orthod August 1983.

62. Gjerdet NR, Here H. Metal release from heat-treated orthodontic archwires.

Acta Odontol Scand 1987;45:409-414. Oslo. ISSN 0001-6357.

Bibliography

70 | P a g e

63. Margret Rosa Grimsdottlr, Nils R. Gjerdet, Arne Hensten-Pettersen

Composition and corrosion of in vitro orthodontic appliances.AM J

ORTHOD DENTOFAC ORTHOP 1992;101:525-32.

64. N. Staffolani, F. Damiani, C. Lilli, M. Guerra, N.J. Staffolani, S. Belcastro, P.

Locci. Ion release from orthodontic appliances. Journal of Dentistry 27 (1999)

449–454

65. Neamat Abu-bakr, Linlin Han, Akira Okamoto, and Masaaki Iwaku, Changes

in the mechanical properties and surface texture of compomer immersed in

various media. The journal of prosthetic dentistry volume 84 number 4

66. O Mockers, D Deroze, J Camps. Cyotoxicity of orthodontic bands, brackets

and archwires in vitro. Dental materials 18(2002) 311-317

67. Theodore Eliades, Athanasios E. Athanasiou, In Vivo Aging of Orthodontic

Alloys: Implications for Corrosion Potential, Nickel Release, and

Biocompatibility. Angle Orthodontist, Vol 72, No 3, 2002

68. Nicolas Schiff, Mickaël Boinet, Laurent Morgon, Michèle Lissac, Francis

Dalard and Brigitte Grosgogeat. Galvanic corrosion between orthodontic wires

and brackets in fluoride mouthwashes. European Journal of Orthodontics 28

(2006) 298–304 doi:10.1093/ejo/cji102.Advance Access publication 20

January 2006

69. Maja Kuhta; Dubravko Pavlin; Martina Slaj; Suzana Varga; Marina Lapter-

Varga, Mladen Slaj.Type of Archwire and Level of Acidity:Effects on the

Release of Metal Ions from Orthodontic Appliances. The EH Angle Education

and Research Foundation DOI: 10.2319/083007-401.1.

Bibliography

71 | P a g e

70. Marcin Mikulewicz & Katarzyna Chojnacka. Trace Metal Release from

Orthodontic Appliances by In Vivo Studies: A Systematic Literature Review.

Biol Trace Elem Res (2010) 137:127–138 DOI 10.1007/s12011-009-8576-6

71. TP Chaturvedi, SN Upadhayay. An overview of orthodontic material

degradation in oral cavity. Indian J Dent Res, 21(2), 2010

72. Antonio Jos_e Ortiz,a Esther Fern_andez,b Ascensi_on Vicente,a Jos_e L.

Calvo,c and Clara Ortiz Metallic ions released from stainless steel,nickel-free,

and titanium orthodontic alloys: Toxicity and DNA damage. Am J Orthod

Dentofacial Orthop 2011;140:e115-e122

73. Hend Salah Hafez, Essam Mohamed Nassef Selim, Faten Hussein Kamel Eid,

Wael Attia Tawfik, Emad A. Al-Ashkar, and Yehya Ahmed Mostafa.

Cytotoxicity, genotoxicity, and metal release in patients with fixed orthodontic

appliances: A longitudinal in-vivo study. Am J Orthod Dentofacial Orthop

2011;140:298-308

74. R. S. Senkutvan, Sanjay Jacob, Anila Charles, Vaishali Vadgaonkar, Suruchi

Jatol-Tekade, Parag Gangurde. Evaluation of nickel ion release from various

orthodontic arch wires: An in vitro study. Journal of International Society of

Preventive and Community Dentistry January-April 2014, Vol. 4, No. 1

75. Fariborz Amini & Mobina Mollaei & Saghar Harandi & Vahid Rakhshan,

Effects of Fixed Orthodontic Treatment on Hair Nickel and Chromium Levels:

A 6-Month Prospective Preliminary Study. Biol Trace Elem Res,17 November

2014 DOI 10.1007/s12011-014-0188-0.

76. Fariborz Amini, Mahsa Shariati, Farhad Sobouti, and Vahid Rakhshan, Effects

of fixed orthodontic treatment on nickel and chromium levels in gingival

Bibliography

72 | P a g e

crevicular fluid as a novel systemic biomarker of trace elements: A

longitudinal study. Am J Orthod Dentofacial Orthop 2016;149:666-72.

77. Kumar RV, Rajvikram N, Rajakumar P, Saravanan R, Deepak VA,

Vijaykumar V. An Accurate Methodology to detect Leaching of Nickel and

Chromium Ions in the Initial Phase of Orthodontic Treatment: An in vivo

Study. J Contemp Dent Pract 2016;17(3):205-210.

78. Magnusson, B., Bergman, M., Bergman, B. & Soremark, R.: Nickel allerg)-

and nickel-containing dental alloys. Scand. J. Dent. Res. 1982: 90: 163-167.

79. Luis Blanco-Dalmau, Harold Carrasquillo-Albert and Juan Silva-Parra, A

study of nickel allergy. The journal of prosthetic dentistry july 1984 volume 52

number 1.

80. Lilian Staerkjaer and Torkil Menne. Nickel allergy and orthodontic treatment.

European Journal of Orthodontics 12 (1990) 284-289.

81. Justin K Bass, Howard Fine, George J Cisneros. Nickel hypersensitivity in

orthodontic patients. Am J Orthod dentofac orthop 1993;103:280-5.

82. J. D. Bumgardner, J. Doeller, and L. C. Lucas. Effect of nickel-based dental

casting alloys on fibroblast metabolism and ultrastructural organization.

Journal of Biomedical Materials Research, Vol. 29, 611-617 (1995).

83. Heidi Kerosuo, Arja Kullaa, Eero Kerosuo, Lasse Kanerva, and Arne Hensten-

Pettersen, Nickel allergy in adolescents in relation to orthodontic treatment

and piercing of ears. AM J ORTHOD DENTOFAC ORTHOP 1996;109:148-

54.

84. Gabriele Schuster, Ralf Reichle, Radha Ranei Bauer, Peter M. Schopf.

Allergies Induced by Orthodontic Alloys: Incidence and Impact on Treatment.

J Orofac Orthop 2004;65:48–59. DOI 10.1007/s00056-004-0312-4.

Bibliography

73 | P a g e

85. Marisa Cristina Leite Santos Genelhu, Marcelo Marigo, Lúcia Fraga Alves-

Oliveira, Luiz Cosme Cotta Malaquias, and Ricardo Santiago Gomez.

Characterization of nickel-induced allergic contact stomatitis associated with

fixed orthodontic appliances. Am J Orthod Dentofacial Orthop 2005;128:378-

81.

86. Kristen K. Volkman, Michael J. Inda, Peter G. Reichl, and Michael C.

Zacharisen. Adverse reactions to orthodontic appliances in nickel-allergic

patients. Allergy Asthma Proc 28:480 –484, 2007; doi:

10.2500/aap.2007.28.3018.

87. J. Noble, S. I. Ahing,

N. E. Karaiskos,

W. A. Wiltshire. Nickel allergy and

orthodontics, a review and report of two cases. BRITISH DENTAL JOURNAL

VOLUME 204 NO. 6 MAR 22 2008.

88. Olga Elpis Kolokitha; Evangelia Chatzistavrou. A Severe Reaction to Ni-

Containing Orthodontic Appliances. Angle Orthod. 2009;79:186–192.

89. Ronny Fors, Berndt Stenberg, Hans Stenlund and Maurits Persson. Nickel

allergy in relation to piercing and orthodontic appliances – a population study.

Contact Dermatitis 3 March 2012. doi:10.1111/j.1600-0536.2012.02097.x.

90. Lina Gölz, Spyridon N. Papageorgiou and Andreas Jäger. Nickel

hypersensitivity and orthodontic treatment: a systematic review and meta-

analysis. Contact Dermatitis 24 February 2015. doi:10.1111/cod.12392

91. Romito LM. Introduction to nutrition and oral health. Dent Clin North Am

2003;47:187‑207.

92. Yetley EA, Beloian AM, Lewis CJ. Dietary methodologies for food and

nutrition monitoring. Vital Health Stat 4 1992;27:58-67.

Bibliography

74 | P a g e

93. Ministry of Health and Family Welfare, Government of India. MDS Course

Regulation 2007. Dental Council of India, Ministry of Health & Family

Welfare, Government of India; 2007.

dietary habits influence on trace element release from

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