[Prevalence of normal occlusion and malocclusion in Bauru (Sao Paulo) students. 2. Influence of socioeconomic level].

We have evaluated 2,416 children of both sexes from Bauru, with mixed dentition, at the age between 7 and 11 years, enrolled in 18 public and private schools. The data regarding their occlusal conditions were written down in index cards previously elaborated to make possible the percentual calculation and the illustrative graphics. In this article we propose to find out the percentage of normal occlusion and distribution of malocclusions, according to the anteroposterior relationship between the dental archs (following the ANGLE3 classification) and their social-economical status. The results show a low percentual of normal occlusion, in total of 11.47% from the studied population. Class I malocclusion was the most prevalent (55%), followed by class II (42%) and, finally, by class III (3%). The social-economical condition had an influence upon the percentual of normal occlusion and class I malocclusion. In a lower social-economical level there was an increase in the percentual of class I malocclusion to the detriment of the reduction of normal occlusion. Class II and III malocclusions were not influenced by the social-economical status.