Surgical treatment of type III temporomandibular joint ankylosis with a lateral arthroplasty while retaining the medially displaced condyle

We discuss our findings on the retention of the medially displaced residual condyle during the treatment of type III temporomandibular joint ankylosis, as well as the postoperative results observed during follow-up. Thirty-two patients with type III temporomandibular joint ankylosis that met the inclusion criteria of the study were included as subjects. The morphological integrity of the medially displaced residual condyle was verified in all of the participating patients through the use of cone beam computed tomography. The duration of the ankylosis ranged from 2 to 12 years. The maximum length that patients were able to open their mouths ranged from 6 mm to 14 mm. The surgical treatments used in this report included the separation of bony fusions between the condyle and the glenoid fossa, resection of the ankylosed sites, preservation of the displaced condyles in their medial position and suturing the remains of the disc to its typical position or taking the temporalis myofascial flap instead. The long-term results were evaluated by computed tomography and clinical follow-up examinations. Three-year postoperative follow-up examinations were performed for all of the patients included in this study. No recurrences were observed in the patients who adhered to the postoperative therapeutic advice. Patients had an average maximal mouth opening distance of 34.50 ± 5.75 mm as recorded during the final follow-up examination. The released medially residual condyle can still function normally in temporomandibular joint movement and without reankylosis after a bone fusion resection. The displaced condyle should thus be preserved instead of being removed during the treatment of type III temporomandibular joint ankylosis.