Resumo

ROSSI JUNIOR, Wagner Costa et al. Masseter and Extraction of Third Molars: Electromyographic Evaluation. Rev. cir. traumatol. buco-maxilo-fac. [online]. 2011, vol.11, n.2, pp. 101-108. ISSN 1808-5210.

Proposition: to evaluate for electromyography the masseter muscle, four hours before and forty eight hours after surgery, during rest, forced centric occlusion and maximum mouth opening, in patients undergoing extraction of third molars.Methodology: were selected 10 subjects with lower third molars mesioangulados rights, class II B position, female, aged between 18 and 25. The third molars were extracted from the right side. Results: electromyographically, the results showed significant differences (p <0.05) in right masseter muscle at rest, with an increase electrical activity of 44,07% between pre and post operatively while in centric occlusion forced a decline in activity of 68,68%. In left masseter, both at rest and forced centric occlusion, there were no statistically significant differences (p> 0.05). At maximum mouth opening was an increase of electrical activity in right and left masseter, between the preoperative and postoperative period of 119.96% and 93.97%, respectively (p <0.05). Conclusions: the extraction of lower third molars change activity of masseter muscle, contributing to the onset of trismus.

Palavras-chave : electromyography; exodontia; trismus..