Prospective cross-sectional study assessing prevalence and factors affecting trismus after multimodal treatment for oral cancers.

Trismus is a common complication following treatment for oral cancers. However, its incidence in site-specific cancers is not adequately studied. The purpose of this study was to assess the prevalence and risk factors associated with trismus in treated patients with oral cancer.The maximal mouth opening in treated oral cancers was measured. Logistic regression analysis was performed to find risk factors for developing trismus in the entire cohort and in a subgroup of patients with gingivobuccal complex cancers.A total of 401 patients were enrolled. The prevalence of trismus was 72.8%. On multivariate analysis, adjuvant therapy and submucous fibrosis were independent predictors. Reconstruction and method of reconstruction did not affect trismus. Bialveolar resections had significantly higher incidence of trismus.High prevalence of trismus was seen in patients following multimodal therapy for oral cancers. Adequate reconstruction alone may not prevent trismus and aggressive rehabilitation is key to its prevention.