Dental caries status of 12-year-old students in the state of Mexico.

A total of 2275 schoolchildren 12 yr of age from the four health regions of the State of Mexico were examined for the prevalence and severity of dental caries. The proportion of caries-free children was only 10%, and the DMFS index was 6.94. 78% of the index derived from decayed surfaces, and 19% from filled surfaces. Pits and fissures of the permanent first molars were the most frequently affected surfaces. Higher dental caries scores were found in rural areas compared with the urban centers. No significant relationship was found between use of dentifrice and dental caries. Several reasons for this lack of relationship are discussed. 10% of the children account for 23% of the DMFS index. Results indicate the need to aim preventive and restorative programs at the whole population as well as at specific high risk groups or individuals.