Occlusal-supporting ability of individual maxillary and mandibular teeth

This study aimed to analyse occlusal force, area and pressure for individual maxillary and mandibular teeth by assessing their occlusal-supporting abilities. Ninety-nine subjects (49 men and 50 women; average age, 24·7 ± 3·4 years; range, 20-37 years) performed maximal voluntary clenching twice for 3 s in both the intercuspal position and the intercuspal position with sliding movement from edge-to-edge occlusion, with a pressure-sensitive sheet placed between the maxillary and mandibular dental arch. Occlusal force, area and pressure of individual teeth were calculated by colour development in the pressure-sensitive sheet with special analytical equipment and software. Occlusal contact condition of individual teeth was confirmed using the intra-occlusal record. All data were analysed using unpaired Student's t-test, Kruskal-Wallis test and Scheffe's test for multiple comparisons with a significance level of P < 0·05. The occlusal pressure in the intercuspal position with sliding movement from edge-to-edge occlusion was adopted as the representative occlusal-supporting ability for each individual tooth, although there were, in part, statistically significant differences in the effects of laterality, performance and gender. Overall, the occlusal pressure increased gradually from the central incisor, peaked at the canine or first premolar and decreased sharply-and significantly (P < 0·01)-towards the second molar. We conclude that the occlusal pressure of individual teeth can be used as an indicator of occlusal-supporting ability. This is therefore proposed as a possible suitable parameter for epidemiologic research, specifically for verifying the relationship between occlusal-supporting ability and status of residual periodontal ligament support.