Masticatory efficiency in class II and class III dentofacial deformities.

Masticatory efficiency may be impaired in individuals with dentofacial deformities. The objective of the present study was to determine the condition of masticatory efficiency in individuals with dentofacial deformities. 30 patients with class II (DG-II) and 35 patients with class III (DG-III) dentofacial deformity participated in the study, all had an indication for orthognathic surgery. 30 volunteers (CG) with no alterations of facial morphology or dental occlusion and with no signs or symptoms of temporomandibular joint dysfunction also participated. Masticatory efficiency was analysed using a bead system (colorimetric method). Each individual chewed 4 beads, one at a time, over 20s measured with a chronometer. The groups were compared in terms of masticatory efficiency using analysis of variance (ANOVA), with the level of significance set at P<0.05. Masticatory efficiency was significantly greater in CG (P<0.05) than in DG-II and DG-III in all chewing tasks tested, with no significant difference between DG-II and DG-III (P>0.05). It was observed that the presence of class II and class III dentofacial deformity affected masticatory efficiency compared to CG, although there was no difference between DG-II and DG-III.