Efeito de interferências oclusais excêntricas artificias no Desempenho mastigatório: um ensaio clínico randomizado duplo-cego

Abstract

Occlusal interferences lead to changes on mandibular kinematic in order to compensate and improve function. However, the particular effect for different kind of eccentric disturbances on comminuting capacity was still not considered. To determine the immediate effect of eccentric occlusal interferences on masticatory performance. This crossover clinical trial included 12 healthy dentate, aged 25.2 ± 3.3 years, whichwere submitted to seven kinds of interferences: uni- and bilateral laterotrusive, uni- and bilateral mediotrusive, protrusive, dummy, and control (no interference). The interferences were planned in semi-adjustable articulator, fabricated with composite resin and adhered on lower first molars maintaining maximum intercuspation of subjects. Masticatory performance and chewing rate until 20 cycles was evaluated by comminution of silicone test food and multiple sieve method. For each condition, interferencesremained in mouth until complete the tests, after that, 1 week was used as a washout period. Subjects in uni- (4.94 ± 0.41 mm) and bilateral (4.81 ± 0.49 mm) laterotrusive, bilateral mediotrusive (4.65 ± 0.50 mm) and protrusive (4.83 ± 0.54 mm) conditions showed the highercomminuted median particle sizes (p < 0.05), while with the control (4.01 ± 0.52 mm) and dummy (4.18 ± 0.58 mm) settings they presented the lower values (p < 0.05). Only with uni- and bilateral laterotrusive interferences, subjects showed narrower dispersion of comminuted particles (p < 0.05). There were no differences among conditions (p = 0.1944) to chewing rate data. The findings suggested that eccentric occlusal interferences decrease the masticatory performance.