A five-year review of the OMX temporomandibular prosthetic total joint replacement system

The aim of this study was to undertake a 5-year review of the OMX temporomandibular prosthetic total joint replacement system (OMX-TMJ).

Data was collected from patients who had an OMX-TMJ implanted between May 2015 and November 2020 at Epworth-Freemasons and St. Vincent's hospitals in Melbourne, Australia. The data points included patient demographics, primary diagnosis, and clinical outcomes in terms of visual analogue scale (VAS) for pain, maximum inter-incisal mouth opening, and complication events.

There were 206 OMX-TMJ devices implanted in 151 patients over the 5-year study period. The vast majority were female patients (n = 137, 90.7%) with a mean age of 44.8 years (range 20-76 years) at the time of surgery. Most patients presented with primary (idiopathic) osteoarthritis (119 joints-57.8%) that failed to respond to conservative measures. Based on a mean follow-up period of 36 months (range 12 months to 73 months), the average mouth opening improved from 30.8 mm pre-surgery to an average of 39.1 mm following OMX-TMJ surgery (p < 0.05). Joint pain (VAS: 0-10) significantly improved from 6.14 pre-surgery to 0.87 following OMX-TMJ surgery (p < 0.001). Twenty-one patients (13.9%) experienced device-related complications which resulted in explantation of 7 (3.4%) OMX-TMJ devices over the 5-year period.

This study shows that the OMX-TMJ prosthetic total joint replacement system is a reasonably safe, versatile, and reliable implant that effectively improves mandibular opening and reduces joint pain across a broad range of end-stage TMJ disorders.