Comparison of biting forces in different age and sex groups: a study of biting efficiency with mobile and non-mobile teeth.

This study aimed (1) to investigate the influences of sex, age and number of teeth on biting ability through a descriptive survey, and (2) to compare the biting ability between the subjects with and without mobile teeth in a case-control study. A total of 687 subjects cooperated in the descriptive survey. Each subject bit on a pressure detecting sheet with their maximum biting force. Three indices of biting ability: biting pressure (MPa), biting force (N) and occlusal contact area (mm2) were calculated from the impressed marks on the sheet using a high vision video processor system. These indices were correlated well with the number of teeth according to the multiple regression analysis. In the case-control study, matching procedures with sex, age and number of teeth were performed between the subjects with and without mobile teeth. No differences in the three indices were observed between the two well-balanced groups. The results showed that the number of teeth is most important to maintain biting ability, and that the presence of mobile teeth does not always reduce biting ability.