An electromyographic evaluation of orbicularis oris and masseter muscle in pretreatment and posttreatment patients of oral submucous fibrosis: A prospective study

Abstract

Background: Oral submucous fibrosis (OSMF) is a chronic disease of insidious onset featuring the deposition of fibrous tissue in the submucous layer of the palate, fauces, cheek, lips, pharynx, and esophagus. The underlying muscles of mastication may be affected resulting in trismus and disability due to muscle hypertrophy. Aims and Objectives: To evaluate the electromyographic activity of masseter and orbicularis oris muscles in patients with OSMF and to compare pretreatment and posttreatment activity of masseter and orbicularis muscles in patients with OSMF and with healthy control. Materials and Method: The study comprised 60 individuals. They were divided into two groups. One group was experimental/study group comprising 30 clinically and histopathologically diagnosed patients with OSMF and control group included another 30 healthy age- and sex-matched individuals. The electromyographic activity was evaluated among study group and control group, pre- and posttreatment patients with OSMF. The results were statistically evaluated using Student's t-test, paired t-test, analysis of variance test, and Bonferroni test. Results: The results showed that electromyographic activity of both the muscles in control group showed statistically significant decreased activity when compared with patients with OSMF. Patients with OSMF posttreatment showed statistically significant decreased activity when compared with pretreatment patients. Conclusion: Electromyography can serve as a useful aid in detecting the involvement of the muscles of mastication and muscle of facial expression in patients with OSMF and effect of the treatment on the muscular activity in patients with OSMF.