Modified Cut for Gap Arthroplasty in Temporomandibular Joint Ankylosis

Temporomandibular joint ankylosis is a debilitating disease affecting the function, esthetics and psychology of the patient. Treatment of this condition aims at establishing not only the function and esthetics but also aims to prevent reankylosis. Among the different treatment modalities, interpositional gap arthroplasty followed by aggressive jaw physiotherapy is considered most effective. This is achieved by making two horizontal osteotomy cuts at a distance of 10-15 mm in the TMJ region. The gap is then interposed with an autogenous or alloplastic graft material. However, during the application of a jaw stretcher intraoperatively with the surgical site open and with the jaw wide open, a bony contact was seen to occur between the posterior aspect of the upper and lower osteotomy cuts. Taking this into consideration, the lower osteotomy cut is modified by making the posterior one-third cut divergent. This eliminates the bony contact during maximum mouth opening and thus prevents the chances of reankylosis as well.