Role of coronoidectomy and temporalis myotomy in surgical management of oral submucous fibrosis.

PURPOSE: The involvement of temporalis muscle fibers by oral submucous fibrosis (OSMF) and the procedure of coronoidectomy and temporalis myotomy in the surgical treatment protocol for the disease is a controversy. The primary objective of this study is to evaluate the histopathological changes in temporalis muscle fibers in patients undergoing surgical treatment for OSMF and to authenticate the importance of temporalis myotomy and coronoidectomy in surgical treatment protocol. METHOD: A 3-year prospective study was conducted to assess the histopathological changes in temporalis muscle in surgically treated OSMF cases. The predictor variables were drawn from demographic characteristics (age and gender) etiology, and mouth opening. The outcome variables were histopathological assessment of temporalis muscle fibers for parameters suggestive of degenerative changes and fibrosis changes at cellular level. RESULTS: Out of 56 patients, 30 patients were had surgical intervention. Twenty-eight (93.3%) were male and 2 (6.6%) were female with a ratio of 14:1. Histopathological examination of temporalis muscle fibers revealed hyalinization of muscle fibers in 80% of the patients followed by loss of striation (73.33%), fragmentation (60%), nucleus internalization (33.33%), infiltration of macrophages and other inflammatory cells (20.67%), multiple nuclei (20%), and swollen muscle fibers (6.67%). Mean preoperative mouth opening was 12.4 and post-operatively 41.3 mm on 1-year follow-up and this was stable on further follow-up. CONCLUSION: The results of this study suggest involvement of temporalis muscle with disease itself and the justification for coronoidectomy and temporalis myotomy in the surgical protocol was established.