Nodular fasciitis in the masticator space eroding into the mandible: a case report

•The first case of nodular fasciitis in the masticator space eroding the mandible.•Steroid injections diminished lesion size but did not lead to resolution.•Treatment consisted of wide local excision with temporomandibular joint reconstruction.

Nodular fasciitis is a benign soft tissue neoplasm of mesenchymal origin. It is usually characterized by rapid growth, infiltrative behavior, and heterogeneous histopathology, which can make diagnosis difficult and lead to delayed management. It has a 15%-20% occurrence rate in the head and neck and occurs rarely intraorally. In this report, we discuss an unusual case of nodular fasciitis originating in the masticator space and destroying the ascending ramus of the mandible. The treatment involved complete resection of the lesion and reconstruction with a temporomandibular joint prosthesis. At 24 months after surgery, the patient showed a return to normal function with no signs of recurrence.