Masticatory performance is influenced by masticatory muscle activity balance and the cumulative occlusal contact area

Abstract

ObjectiveTo investigate the influence of masticatory muscle activity balance, occlusal contact area balance and the area of occlusal contact on masticatory performance in healthy dentate adults. DesignThis cross-sectional study included ninety-three healthy subjects with complete dentition. Surface electromyography (sEMG) was used to record bilateral anterior temporalis activity and masseter muscle activity during maximum voluntary clenching and while chewing a test food. Seven levels of area of occlusal contact and near contact (ACNC) were registered and calculated cumulatively. The percentage overlapping coefficients were calculated for both muscle groups at maximum voluntary clenching and chewing and all levels of ACNC. Masticatory performance was measured by determining the median particle size of frankfurter sausage after 15 chewing cycles. Pearson’s correlation and stepwise multiple linear regression analyses were used to assess the correlations between variables and the influence of the variables on masticatory performance, respectively, at the 0.05 level of significance. ResultsMuscle balance during clenching and chewing, all near contact levels of cumulative ACNC and ACNC balance correlated negatively with median particle size (P < 0.05). The model based on stepwise multiple linear regression analysis showed muscle balance during clenching and cumulative ACNC at < 250 μm influenced median particle size. ConclusionMasticatory muscle activity balance during maximum voluntary clenching and the cumulative amount of near contact area were associated with masticatory performance, suggesting the amount of occlusal contact area—as well the balance of masticatory muscle activity—play a role in masticatory performance.