Temporomandibular joint (TMJ) ankylosis is a severe condition that leads to joint destruction, resulting in mandibular hypomobility and impairments in speech, mastication, and oral hygiene. The most common causes of TMJ ankylosis include local infections and facial trauma. Post-trauma physiotherapy plays a crucial role in preventing its occurrence. This article presents the case of a patient who sustained facial trauma and subsequently developed bilateral TMJ ankylosis. The treatment involved interpositional arthroplasty using a temporal muscle flap and bilateral coronoidectomy. These techniques successfully restored mouth opening, reestablished TMJ function, and improved the patient’s quality of life.