epidemiology and prevention of dental caries

Departement of public health dentistry

Epidemiology ,prevenTion of dental caries

Presented by,Shiji margaretCRRI

contentEpidemiology definitionDental caries definitionRelation between diet and dental cariesCaries factorsGlobal distributionDietVariation of caries within the mouthTypes of dental cariesAgent factors of dental cariesRisk factorsPreventionConclusion

Epi = uponDemos = peoplelogy = sTUDYEpidemiology = the science which deals with what falls upon people…..

definition

The study of distribution and determinants of health related status or events in a specified population and this application of this study for the control of the diseases

dental caries

It is an infectious microbial disease of teeth that results in the localized destruction and dissolution of the calcified tissues.

Low Caries incidence existed in Ancient Man

•Examination of ancient skulls

shows that:

Low caries incidence in the ancient man is due to diet which was :

Comparatively low in carbohydrates.

Natural (unrefined) diet.

Coarse & not fully prepared or cooked.

Relationship between diet and dental caries

Bacterial enzyme + fermentable carbohydrates = acid

Acid + enamel = dental caries

The classic Vennediagram of caries.

Must have a tooth, plaque bacteria, fermentable carbohydrate, saliva, and enough time in order for a carious lesion to develop .

Caries results when all of the factors that contribute to caries overlap. (red color, center).

Several factors influencing each component, ( see the diagram,) affect the rate and severity of the caries.

Caries Factors

Current global distributionDuring most of the 20th

century, dental cariespattern was :I. High prevalence in

developed countries & higher socioeconomic group.

II. Low prevalence in developing countries with less economic development.

Caries was referred to as “a disease of civilization.”

Global DistributionThe most obvious reason for this

historical pattern is diet; the high level of consumption of refined carbohydrates in developed countries in contrast to diets low in fermentable carbohydrates in poorer societies where hunting and farming are the main source of food.

High level of consumption of refined carbohydrates in developed countries led to increase in cariogenic bacteria.

Diet low in fermentable carbohydrates in developing countries surviving on farming & hunting lower level of cariogenic bacteria.

Explanation of this pattern is :

diet

DietIntake of refined carbohydrates

especially sucrose (sugar) is considered a strong etiologic factor in the causation of dental caries.

The distribution pattern of dental caries closely follows that of plaque. Thus, the sites in the mouth which are most prone to caries are those where plaque accumulates.

Variation of caries within the mouth:

I- Types of dental caries

1)Pit & fissure caries:

It is the first to appear in the mouth.

Pits &fissure surfaces constitute the most susceptible surfaces in the mouth.

2) Proximal caries:It is the next to appear

in the mouth.It is related to plaque

accumulation in the non-self cleansing areas (beneath the contact points).

3) Cervical caries

Is the third type of dental caries that occurs uniformly throughout life.

It is related to progressive changes in the free gingival margin, poor oral hygiene & decreased salivary flow (xerostomia)

4) Root caries:Occurs usually in old

age (60 y<).Root surfaces become

exposed by gingival recession in advancing age.

These exposed areas provide perfect areas for plaque accumulation.

Agent Factors of Dental CariesMicroorganismsMainly Streptococcus mutans are responsible

for initial development of dental caries with contribution of other species such as:

Lactobacillus acidophilus Lactobacillus caseiStreptococcus salivariusStrpetococcus milleriStreptococcus sanguisActinomycis (root caries)

The host Risk Factors

1- Age. 2- Gender. 3- Race. 4- Genetic & familial.5- Role of saliva.

Age Caries was considered a

childhood disease because all susceptible tooth surfaces become carious during early child years and few carious lesions are affected during adulthood.

Caries increases progressively by age, and the increase is more slowly during adult years

GenderIt is observed that caries prevalence is higher in females than in males of the same age.

Race

Early studies, observed that some races as those in Africa & India, had high degree of caries resistance than “Europeans”.

Recently, the concept of racial differences have been faded, and the evidence reveals that the global differences are the result of environment. .

Familial & genetic patternDental caries has

long ago shown to be grouped according to families

Members of the same household were found to be alike in their caries pattern than between unrelated groups of individuals.

Such familial tendency may be due to:

1- Interfamilial bacterial transmission, especially from mother to baby.

2- similarity in dietary & oral hygiene habits. OR,

3- Genetic factor: as inheritance of tooth structure (deep narrow pits & fissures) or special arch form (irregularities & crowding).

Socioeconomic status• It is a measure of the individual’ background; education, income, occupation, and attitudes and values.

• It is inversely related to the status of many disease.

• It is a powerful determinant of caries status in any community.

Role of Saliva Diluting effect on fermented food residues.

Buffering capacity to neutralize acid end products resulting from such fermentation.

Provides ions for remineralization of early carious lesions.

Provides antibacterial, antifungal and antiviral agents.

Prevention of dental caries

1. Neutralize the plaque acids:

This can be done by adding base or adding buffers such as sodium bicarbonate (baking soda) to the saliva to boost its ability to neutralize acids.

2. Improve hygiene:

With bacterial levels low, less acid is produced. Plaque layers don’t have a chance to grow thick; Saliva can penetrate better to the enamel surface through thin layers of plaque.

3. Introduce antimicrobials:

Since caries is a disease caused by bacteria, simply eliminating the bacteria or controlling their growth will reduce the caries incidence. Chlorhexidine, xylitol, ozone, even experimental antibodies, have been used to control bacterial growth

4. Stimulate saliva:

Saliva contains numerous components - that fight tooth decay buffers, remineralizing minerals, antimicrobial enzymes, antibodies.

5. Topical fluorides: Fluoride added to the remineralizing incipient lesion increases the enamel crystals’resistance to dissolution by plaque acids

DENTAL CARIES is so prevalent that the only possible solution is the “prevention”. The best way to avoid getting it is to practice good oral hygiene habits

conclusion

THANK U…