Fibromatosis of infratemporal space

Fibromatosis is a rare benign mesenchymal neoplasm which primarily originates in the muscle, connective tissue, fascial sheaths, and musculoaponeurotic structures. It is commonly seen as abdominal tumour but in maxillofacial region, the occurrence of these tumours is very rare and exceedingly rare in infratemporal space. Often misdiagnosed due to its varied clinical behaviour, fibromatosis is benign, slow-growing, infiltrative tumour without any metastatic potential, but is locally aggressive causing organ dysfunction along with high recurrence rate. We report a case of fibromatosis involving the left infratemporal space in a 35-year-old female who presented with chief complaint of limited mouth opening for the preceding 4 years.