Temporomandibular custom hemijoint replacement prosthesis: prospective clinical and kinematic study.

PURPOSE: To evaluate the clinical and functional outcomes of a custom temporomandibular hemijoint fossa/eminence implant prosthesis.

MATERIALS AND METHODS: This prospective cohort study enrolled patients with osteoarthritis of the temporomandibular joint. The primary study variables were pain experience, pain intensity, chewing ability, jaw opening, joint noise, and overall satisfaction of the surgical outcome at 3, 6, and 13 months after surgery. Pre- and postsurgical kinematic analyses measured maximum incisal opening, operated and unoperated condyle translations, and mandibular body axis rotation using mandibular kinematic data combined with patient-specific computed tomographic data. The primary analysis of interest concerned preoperative versus postoperative changes.

RESULTS: The study sample was composed of 36 subjects (mean age, 46 years; 94% female; 40 joints). There were statistically significant improvements between pre- and postoperative measurements for each study variable. The kinematic data documented preservation or an increase of bilateral condylar motion, mandibular axis rotation, and mandibular incisor motion.

CONCLUSIONS: Temporomandibular joint hemiarthroplasty with a custom metal fossa/eminence prosthesis provides satisfactory clinical and functional outcomes when used for advanced osteoarthritis in patients with focal joint pain secondary to computed tomographically documented joint pathology.