dentin hypersensitivity educational teaching resource

DENTIN HYPERSENSITIVITY

Physiology, Etiology, Epidemiology, Diagnosis, and Treatment

Dentin Hypersensitivity

After viewing this lecture, attendees should be able to:

• describe the oral anatomy as it relates to dentin hypersensitivity.• discuss the etiology and physiologic mechanism of dentin hypersensitivity.• describe the prevalence and epidemiology of dentin hypersensitivity.• describe the diagnosis and management of dentin hypersensitivity.


Dentin hypersensitivity is best defined as a “short, sharp, pain arising from exposed dentin in response to stimuli—typically thermal, evaporative, tactile, osmotic or chemical, and which cannot be ascribed to any other form of defect or pathology.”1

• Enamel• Dentin• Cementum• Dental Pulp

The 4 main dental tissues:

Enamel

Dentin

Cementum

Dental Pulp

Oral Anatomy: Dental Tissues

• Anatomic Crown• Anatomic Root• Pulp Chamber

The 3 parts of a tooth:

Anatomic Crown

Anatomic Root

PulpChamber

Oral Anatomy: Dental Tissues

Oral Anatomy:Dental Tissues

Enamel

Dentin

Cementum

Dental Pulp

Oral Anatomy:Dentinal Tubules

• Presence of tubules renders dentin permeable to fluid movement

• Number of tubules per unit area varies

• Dentinal tubules are conical

Dentin

Pulp

Tubule

Fluid Nerve Fibers

Odontoblast Cell

Dentin Hypersensitivity: Physiology

The dental pulp is richly innervated.

According to conduction velocities, the nerve units can be classified into A group—having the conduction

velocity more than 2 m/s and C group—with conduction velocity less than 2 m/s

The sharp, better localized pain is mediated by A delta

fibers, whereas C fiber activation seems to be connected

with the dull radiating pain sensation.

Myelinated A fiber

seems to be responsible for dentin sensitivity.


The most widely accepted mechanism of action for dentin hypersensitivity is the Hydrodynamic Theory, which was first proposed by Gysi in 1900 and

validated by Brannstrom in 1996.2

Mechanism of Dentin Hypersensitivity


There are two essential elements of the hydrodynamic mechanism:2

• Fluid flow through dentinal tubules• Pulpal sensory nerves

Mechanism of Dentin Hypersensitivity

Dentin Hypersensitivity:

Physiology

Two processes required:3

• dentin must be exposed• dentin tubules must be open to:

– dentin surface– patent to the pulp

Hydrodynamic Theory

Enamel

ExposedDentin

RecedingGingiva

Tubules

Odontoblast


Physiology

Trigger stimuli include:3 • Thermal

– Hot– Cold

• Tactile• Evaporative• Osmotic

Hydrodynamic Theory


Physiology

The true physiologic stimulus is the inward or outward fluid

shifts, not the actual trigger.4

Hydrodynamic Theory

Fluid-filledTubules

Dentin NerveFibers

Odontoblast Cell

Dentin Hypersensitivity:Physiology

• Mathews et al (1994– stimuli such as cold causes fluid flow away from

the pulp, produces more rapid and greater pulp nerve responses than those such as heat, which causes an inward flow.

• This certainly would explain the rapid and severe response to cold stimuli compared to the slow dull response to heat

Insert Text Here14


• The dehydration of dentin by air blasts or absorbent paper causes outward fluid movement and stimulates the mechanoreceptor of the odontoblast, causing pain.

• Prolonged air blast causes formation of protein plug into the dentinal tubules, reducing the fluid movement and thus decreasing pain

Insert Text Here15


Hydrodynamic theory showing pain because of fluid

movement

16


Etiology

The most important factor in the etiology of dentin hypersensitivity is exposed dentin.5,6

Hydrodynamic Theory

• The result of gingival recession(exposure of root surfaces)

• The result of loss of enamel from tooth wear or trauma

• Loss of cementum • Removal or absence of a smear

layer

RecedingGingiva

ToothWear

Dentin Hypersensitivity: Etiology

Gingival Recession is caused by:7

• Physiologic factors– Hormonal fluctuations– Poor nutrition– Aging

• Periodontal diseases

– Gingivitis– Periodontitis

• Periodontal therapy– Scaling and root planning

– Surgery

• Restoration margins

• Chronic trauma– Oral hygiene (toothbrushing)– Habits (tobacco smoking &

chewing)

• Predisposing anatomic factors– Thin gingiva– Prominent roots – Dehiscences– Fenestrations– Frenum pulls– Roots moved outside alveolar

housing by orthodontics

• Physical Loss– Abrasion—mechanical– Attrition—tooth/tooth– Abfraction—lesions

• Chemical dissolution– Erosion

-Extrinsic acids -Intrinsic acids

• Multifactorial etiology – Erosion, abrasion, attrition,

abfraction

Tooth Wear can occur as a result of:3,8



Etiology

• Not all exposed dentin is sensitive3

Dentinal Tubules

• Surface appearance

• Open/patent tubules

• Greater number of tubules

• Tubules larger in diameter

• Absence of smear layer

• Tubules open from tooth wear

Characteristics of Sensitive Dentin:

Dentin

ToothWear

RecedingGingiva


• Dentin becomes exposed through enamel or cementum loss and/or gingival recession

• Opening of tubules by removal of the smear layer initiates the lesion

• Disturbed flow stimulates A-beta (A-β) and some A-delta (A-δ) nerve fibers

Understanding Dentin Hypersensitivity Pain4


• Aggressive toothbrushing• Periodontal diseases• Periodontal therapy• Tooth whitening/bleaching

Understanding Dentin Hypersensitivity Pain


Understanding Dentin Hypersensitivity Pain


Etiology

• Erosion—acts alone, or in combination with abrasion to cause enamel loss

• Extrinsic/intrinsic acids cause surface softening of enamel which takes hours to re-harden and results in greater susceptibility to physical insult

Understanding Dentin Hypersensitivity Pain9

3. Strassler HE, Drisko CL, Alexander DC.

• Incidence: 15% (4% to 57%)• Age range: 15 – 70+ years• Peak incidence: 20 – 40 years • Gender: Female > Males

Global Prevalence3


Epidemiology

Pain or discomfort caused by cold, hot, sweet, sour, foods/drinks or tooth brushing.


Epidemiology

• Teeth: Canines (cuspids) and premolars (bicuspids)

• Sites: Buccal cervical regions

Most Commonly Found3

Canine Premolar

Canine

In: Pashley DH, Tay FR, Haywood VB, et al. Dentin Hypersensitivity: Consensus-Based Recommendations for the Diagnosis and Management of Dentin Hypersensitivity.

Frequency of Dentate Adults who Responded Positively to Having or Ever

Having Sensitive Teeth

Dentin Hypersensitivity: Epidemiology

In a multi-national survey conducted with 11,000 adults in 2002, 48% of participants said at some point they had consulted a dentist due to sensitive teeth.10,11

27

Insert Text Here28

Dentin Hypersensitivity: Epidemiology

• Dietary changes – Acidic food/drinks• Periodontal procedures• Cosmetic treatments – Bleaching/whitening12-14

– Restorative• Aging – Retain natural teeth

There are a number of factors that may contribute to an increased prevalence of dentin hypersensitivity:3

Dentin Hypersensitivity: Management

• Differential diagnosis• Exclude or treat other causes

of dentin pain• Identify etiological factors• Prevent, remove or modify

etiological factors• Management/treatment

Management begins with patient education and modification of risk factors15

Dentin Hypersensitivity: Management/Diagnosis

Complete History• Sign and symptoms• Intensity• Frequency and duration• Dietary changes• Other related events

Clinical Examination• Visual assessment• Physical assessment – Dental explorer (probe): tactile stimulus• Periodontal probe

– Depth of periodontal pocket

• Percussion testing• Response to cold air

Dentin Hypersensitivity is a diagnosis of exclusion

Radiographic examination• Rule out periapical lesions

Differential Diagnosis• Cracked tooth syndrome• Fractured restoration• Chipped teeth• Dental caries• Periodontal disease• Post-restorative sensitivity• Marginal leakage• Pulpitis• Palatogingival groove• Bleaching sensitivity

Needs to rule out:15

Non-Odontogenic Origin• Musculoskeletal• Neuropathic• Neurovascular• Inflammatory (sinusitis)• Systemic (cardiac, herpes, zoster, sickle cell anemia, neoplasm)• Psychogenic• Referred pain


• Tooth sensitivity is one of the most common forms of dental pain• Usually occurs on the side opposite the dominant hand• The buccal cervical sites on the canine and pre-molars are the most

common sites for tooth sensitivity

Incidences3


Dentin Hypersensitivity:Management/Diagnosis

• Root sensitivity is typically a result of gingival recession that may be compounded by tooth wear

• Sensitivity in the crown may be caused by some form or combination of factors attributed to tooth wear

Tooth Wear3

RecedingGingiva

DentinWear

Enamel Wear

• All forms of vital tooth bleaching are associated with some level of sensitivity• Bleaching sensitivity is caused by the easy passage of hydrogen peroxide and

urea through the intact enamel, through the dentin in the interstitial spaces into the pulp within 5 to 15 minutes16

Tooth Whitening/Bleaching16



Tooth hypersensitivity differs from dentinal or pulpal pain.

In case of dentin hypersensitivity, patient’s ability to locate the source of pain is very good, whereas in

case of pulpal pain, it is very poor

The character of the pain does not outlast the stimulus; the pain is intensified by thermal

changes, sweet and sourThe pain can be duplicated by hot or cold

application or by scratching the dentinInsert Text Here

36

Prevention and Treatment of Bleaching Hypersensitivity

16. Pashley DH, Tay FR, Haywood VB, et al.



• Cold beverages • Eating cold food• Breathing cold air• Toothbrushing• Improper dental floss use• Eating sour/acid food• Eating sweet/sugary liquids

and foods• Bleaching/whitening procedures

Occurrence of pain:3

• Thermal—pain in response to cold or hot• Evaporative—blowing air on the tooth surface• Tactile—pain in response to touch• Osmotic—pain in response to sugar/acid• Dental treatment—this type of sensitivity is transient and will resolve

with removal of treatment or over time


Sensitivity may occur in response to various stimuli:3

Dentin Hypersensitivity:Management/Etiological Factors

Tooth Wear/Erosion:• Use fluoride-rich dentifrice • Behavior modification • Decrease abrasive forces• Application of topical fluoride• Enhance the defense mechanisms of the body• Provide nutritional counseling

Management of Pre-disposing Factors17

Dentin Hypersensitivity:Management/Etiological Factors

Gingival Recession:• Correct toothbrushing technique• Plaque control• Avoidance of harmful habits• Periodontal disease management• Replacement of restorations with defective margins• Smoking cessation

Management of Pre-disposing Factors17

Dentin Hypersensitivity:Treatment

• Obturate tubules or alter fluid flow in dentinal tubules

• Modify or block pulpal nerve response

Management of Dentin Hypersensitivity3,4

KNO3

CHEMICAL AGENTS18 Nerve Inactivators

• Potassium salt (nitrate-KNO3)

Tubule Obtundants• Strontium chloride• Calcium hydroxide• Fluorides• Sodium citrate• Potassium oxalate• Iontophoresis with NaF

Management of Dentin Hypersensitivity

Protein Precipitators• Strontium chloride• Silver nitrate• Formaldehyde

Dentin Hypersensitivity: Treatment

Potassium salt (nitrate-KNO3)

Insert Text Here44

Potassium salt (nitrate-KNO3)

• Potassium ion is a desensitization agent because it diffuses through dentin tubules and increases the extracellular potassium concentration at the

nerve ending, eliminating the potassium ion concentration gradient across the nerve cell membrane. Without this concentration gradient, the nerve cell will not depolarize and will not respond to stimuli; thus the sensation

of pain will not be transmitted. Potassium ion can be delivered in a variety of salt forms (e.g., potassium nitrate, potassium citrate). The most

common potassium salt used in sensitivity dentifrices is potassium nitrate (KNO3)

Insert Text Here45

Insert Text Here46

Tubule Blocking or Occluding Agents

47

Insert Text Here48


• Calcium sodium phosphosilicate (Novamin®, Sensodyne® Repair & Protect).

• In saliva, Novamin® releases calcium and phosphate ions and raises the pH. Under these conditions, calcium phosphate salts precipitate from solution to not only block dentin tubules but also to form an insoluble calcium phosphate layer on the surface of enamel

Insert Text Here49


Insert Text Here50

PHYSICAL AGENTS18

Dentin Hypersensitivity: TreatmentManagement of Dentin Hypersensitivity

• Composite resins• Bonding agents• Sealants• Glass-ionomer cements• Varnishes• Soft tissue grafts• Lasers

Insert Text Here52

Insert Text Here53


At-home treatments—patient applied• Anti-sensitivity dentifrice• Fluoride-based gels• Rinses

Options for Treatment19


In-office by dental professional• Chemicals (oxalates)• Physical agents• Restorations • Endodontic (root canal)• Tooth extraction

Options for Treatment19 (listed as least invasive to most)

Dentin Hypersensitivity: “the common cold of dentistry.”3


Dentin Hypersensitivity—References

1. Ajcharanukul O, Kraivaphan P, Wanachantarak S, et al. Effects of potassium ions on dentin sensitivity in man. Arch Oral Biol. 2007;52(7);632-639.2. Matthews B, Vongsavan N. Interaction between neural and hydrodynamic mechanisms in dentine and pulp. Arch Oral Biol. 1994:39(Suppl):87S-95S.3. Strassler HE, Drisko CL, Alexander DC. Dentin hypersensitivity: its inter-relationship to gingival recession and acid erosion. Inside Dentistry. 2008;29(5

Special Issue):3-8.4. Dentin hypersensitivity: current state of the art and science. In: Pashley DH, Tay FR, Haywood VB, et al. Dentin Hypersensitivity: Consensus-Based

Recommendations for the Diagnosis and Management of Dentin Hypersensitivity. Inside Dentistry. 2008;4(9 Special Issue):8-18. 5. Watson PJ. Gingival recession. J Dent. 1984;12(1):29-35. 6. Smith RG. Gingival recession. Reappraisal of an enigmatic condition and a new index for monitoring. J Clin Periodontol. 1997;24(3):201-205. 7. Dentin hypersensitivity and gingival recession. In: Pashley DH, Tay FR, Haywood VB, et al. Dentin Hypersensitivity: Consensus-Based Recommendations

for the Diagnosis and Management of Dentin Hypersensitivity. Inside Dentistry. 2008;4(9 Special Issue):19-24. 8. Imfeld T. Dental erosion. Definition, classification and links. Eur J Oral Sci. 1996;104(2 (Pt 2)):151-155. 9. ten Cate JM, Imfeld T. Dental erosion. Summary. Eur J Oral Sci. 1996;104(2 (Pt 2)):241-244. 10. Addy, Martin, Dentin hypersensitivity: new perspective on an old problem. Int Dent J. 2002;52:367-375.11. Drisko, CH. Dentin hypersensitivity – dental hygiene and periodontal considerations. Int Dent J. 2002;52;385-393.12. Auschill TM, Hellwig E, Schmidate S, et al. Efficacy, side-effects and patient’s acceptance of different bleaching techniques (OTC, in-office, at home). Oper

Dent. 2005;30(2):155-163.13. Broening WD, Blalock JS, Fraizer KB, et al. Duration and timing of sensitivity related to bleaching. J Esthet Restor Dent. 2007; 19(5): 256-264

Dentin Hypersensitivity—References

14. Haywood VB, Leonard R, Nelson CF, et al. Effectiveness, side effects and long-term status of nightguard vital bleaching. J Am Dent Assoc. 1994;125(9):1219-1226.

15. Dentin hypersensitivity: consensus-based recommendations for the diagnosis and management of dentin hypersensitivity. In: Pashley DH, Tay FR, Haywood VB, et al. Dentin Hypersensitivity: Consensus-Based Recommendations for the Diagnosis and Management of Dentin Hypersensitivity. Inside Dentistry. 2008;4(9 Special Issue):1-7.

16. Considerations for managing bleaching sensitivity. In: Pashley DH, Tay FR, Haywood VB, et al. Dentin Hypersensitivity: Consensus-Based Recommendations for the Diagnosis and Management of Dentin Hypersensitivity. Inside Dentistry. 2008;4(9 Special Issue):25-31.

17. Lussi A, Hellwig E. Risk assessment and preventative measures. In: Lussi A, ed. Dental Erosion: From Diagnosis to Therapy. Basel, Switzerland: Karger; 2006:190-199. Whitford GM. Monographs in Oral Science; vol 20.

18. Dentin Hypersensitivity: Etiology, Diagnosis and Successful Management. Advancements in Oral Health Educational Module. 19. Canadian Advisory Board on Dentin Hypersensitivity. Consensus-based recommendations for the diagnosis and management of dentin hypersensitivity. J

Can Dent Assoc. 2003;69(4):221-226.

dentin hypersensitivity educational teaching resource

Education

etiology dentin

dentin permeable

dehydration of dentin

exposed dentin tubules

dentin surface patent

physiology hydrodynamic

hydrodynamic theory

hydrodynamic mechanism