Objective: To analyze the masticatory efficiency of individuals with class II dentofacial deformity before and 6 months after orthognathic surgery compared to a control group. The study was approved by the Ethics Committee. Sixteen individuals with a diagnosis of class II dentofacial deformity (DG-II), 5 men and 11 women (mean: 27 years) and on 30 control volunteers (CG), 12 men and 18 women (mean: 24 years) participated in the study. Masticatory efficiency was analyzed by the colorimetric method with beads. Each individual chewed four beads capsules (2 in a habitual manner, 2 on both sides), one at a time, being timed for a period of 20 s, with a 3-min interval between chewing episodes. In the statistical analysis, the values of masticatory efficiency were compared in DG-II before and 6 months after orthognathic surgery using the paired Student’s t -test. The masticatory efficiency of DG-II before and 6 months after surgery was compared to that of CG by analysis of variance (ANOVA). There was a statistically significant difference ( p < 0.05) in the masticatory efficiency of DG-II between the period before and after orthognathic surgery both in habitual free mastication and in unilateral mastication. A significant difference ( p < 0.0001) in masticatory efficiency was also observed between CG and DG-II both before and after surgery regarding all masticatory tasks.

Conclusion: Masticatory efficiency improved in individuals with class II deformity after orthognathic surgery, although 6 months after surgery their values of masticatory efficiency were not equal to those of individuals without dentofacial deformity.

Conflict of interest: None declared.