Does Accurate Positioning of the Temporomandibular Joint Titanium Condylar Prosthesis Prevent Complications?

Purpose: Reconstruction of the temporomandibular joint defect is challenging. The purposes of this study were to identify factors associated with the accuracy of positioning of a titanium condylar prosthesis and to measure the association between the accuracy of the condylar prosthesis position and postoperative complications. Materials and Methods: We designed a retrospective cohort study and enrolled a sample of patients whose condyle was reconstructed with an alloplastic condylar prosthesis. The primary predictor variable was the accurate positioning of the prosthesis in the fossa in comparison with the native condyle. The primary outcome variable was the development of postoperative complications related to the inaccurate positioning of the condylar prosthesis. Other variables were included and discussed in detail in the article. In addition, the postoperative pain level was assessed with a visual analog scale score. Because of the small sample size, we elected to use a descriptive data analysis for the research. Results: The final sample was composed of 40 patients, with a mean age of 38 years. A postoperative complication developed in 6 patients (15%), including cutaneous plate exposure after radiation therapy, erosion through the tympanic plate of the condylar fossa, and erosion into the temporal bone. The average displacement of the condylar prosthesis in the patients in whom complications developed was 5.04 mm in the vertical and 1.5 mm in the lateral dimension, which was less than the average of all other patients in the study. Seven patients reported higher levels of pain represented by the visual analog scale score, and this was associated with increased deviation of the condylar prosthesis position by 4.4% and 16.6% in the vertical and lateral dimensions, respectively. Conclusions: This retrospective study showed that the amount of displacement of the temporomandibular joint prosthesis did not correlate with the incidence of complications or postoperative pain. (C) 2018 American Association of Oral and Maxillofacial Surgeons