[3D mandibular distraction planification in a case of severe temporomandibular ankylosis]

When occurring in childhood, temporomandibular ankylosis joint is responsible for complex maxillofacial deformities, including mandibular growth deficiency. We present a case of temporomandibular joint ankylosis associated with severe mandibular asymmetry treated by mandibular bone distraction performed under computer assistance.

A 27-year-old patient presented with a severe facial asymmetry consisting in hypoplasia of the left hemi-mandible and maxilla. Mouth opening was non-existent. The CT-scan showed a left temporomandibular ankylosis. A left mandibular distraction was decided. The distraction characteristics (choice and positioning of the distractor, axis and amount of distraction) were determined preoperatively on the 3D CT-scan. The planning has been transferred to a navigation console (Kolibri®, Brainlab®). A combined intraoral and cutaneous was performed. Navigation allowed for an appropriate placement of the osteotomy line and fixation of the distractor. Distraction was started at the 5th postoperative day at the rate of 1mm per day and lasted 25 days without complication.

3D planning allows for better indication setting, better preparation of the procedure, reducing complications and operative time. It may help as an educational tool for young surgeons and for a better understanding from the patient. Navigation is an accurate method for the transfer of the planning in the operation room.