Surgical navigation system for temporomandibular joint ankylosis in a child: a case report

BACKGROUND: Computer-assisted surgical navigation systems were initially introduced for use in neurosurgery and have been applied in craniomaxillofacial surgery for 20 years. The anatomy of the oral and maxillofacial region is relatively complicated and includes critical contiguous organs. A surgical navigation system makes it possible to achieve real-time positioning during surgery and to transfer the preoperative design to the actual operation. Temporomandibular joint ankylosis limits the mouth opening, deforms the face, and causes an increase in dental caries. Although early surgical treatment is recommended, there is controversy regarding the optimal surgical technique. In addition, pediatric treatment is difficult because in children the skull is not as wide as it is in adults. There are few reports of pediatric temporomandibular joint ankylosis surgery performed with a navigation system. CASE PRESENTATION: A 7-year-old Japanese girl presented severe restriction of the opening and lateral movement of her mouth due to a temporomandibular joint bruise experienced 2 years earlier. Computed tomography and magnetic resonance imaging demonstrated left condyle deformation, disappearance of the joint cavity, and a 0.7-mm skull width. We diagnosed left temporomandibular joint ankylosis and performed a temporomandibular joint ankylosis arthroplasty using a surgical navigation system in order to avoid damage to the patient's brain. A preauricular incision was applied, and interpositional gap arthroplasty with temporal muscle was performed. After the surgery, the maximum aperture was 38 mm, and the limitation of the lateral movement was eliminated. CONCLUSIONS: A navigation system is helpful for confirming the exact target locations and ensuring safe surgery. In our patient's case, pediatric temporomandibular joint ankylosis surgery was performed using a navigation system without complications.