Epidemiology Of Dental Caries

Dental Caries DDental caries is an infectious, communicable disease resulting in destruction of tooth structure by acid-forming bacteria found in dental plaque, in the presence of sugar

Concepts of caries etiology Time Tooth Microorganism Substrate

Current concepts of Dental Caries The development of dental caries is a dynamic process of demineralization of the dental hard tissues by the products of bacterial metabolism, alternating with periods of remineralization

Cyclic Process of Decay Demineralization Remineralization Bacteria plus food makes the saliva very acidic within 5 minutes Saliva is normal 30 minutes after eating

Demineralization / Remineralization

Demineralization / Remineralization

Continuo……. Etiology of dental caries: Tooth susceptibility Bacterial plaque Carbohydrates Oral sugar clearance Time Saliva flow & pH

Continuo……. Epidemiology of dental caries: Host Factors Age Sex Race Emotional disturbance

Agent Factors * Streptococcus mutans…………….initiation of dental caries mutans plus sucrose reduces the pH in the plaque to a critical level of , which can overcome the buffering capacity of saliva and result in demineralization of enamel * Lactobacillus ……………progression of dental caries Lactobacillus counts are significantly higher in patients with open caries lesions

Environmental factors sunshine temperature fluoride nutrition social factors oral environment

Dental caries Crown cariesRoot caries

Occlusal caries

Smooth surface

acute arrested

Continuo……. Dental caries of primary teeth: Sequence of caries in primary dentition is as follows: *mandibular molars followed by maxillary molars, followed by maxillary anterior teeth. * Proximal caries progress more rapidly than occlusal caries and cause higher percentage of pulp exposure. * Caries in lower incisors is unusual except in rampant caries.

Dental caries of permanent teeth: 1- Mandibular first and second molars. 2- Maxillary first and second molars. 3- Mandibular second premolars, maxillary first and second premolars, maxillary centrals and laterals. 4- Maxillary canines and mandibular first premolars. 5- Mandibular centrals, lateral incisors and canines.

ASSESSMENT OF DENTAL CARIES Counts : Number of persons involved by the disease(presence or absence). Proportion : The prevalence of the disease can express as percentage Number per 1oo persons

Rates : Stander unit of population is often used - 1:1000 (10,100,100,10.000……) Intensity: Or severity by using an index

What is the index ? Is a graduated numerical scale with definite upper and lower limits describing the relative status of a population. Irreversible………… caries Reversible……………. gingivitis

MEASUREMENT OF DENTAL CARIES 1- Methods of examination Type 1………… mirror,probe, full mouth x-ray, study model, illumination ( complete examination) Type 2………… mirror,probe, bitewing x-ray, illumination Type 3………… mirror,probe, illumination Type 4…………, tongue depressor, illumination (screening)

Diagnostic criteria - WHO criteria - White spots - Discoloured,rough areas, softening, undermining

Indices for dental caries For permanent teeth : DMF index D……………. Decayed M ……………. Missed F ……………....Filled ( DMFT) OR ( DMFS)

For primary teeth: - def index - dmf index - df index

Number of d + m + f surfaces dmfs Index = ——————————— Total number of primary teeth Number of d + m + f tooth dmf Index = ——————————— Total number of primary teeth