A Systematic Review of the Success of Temporomandibular Joint Replacement Using Stock Prosthesis Compared to Custom Prosthesis

Objectives: Patients with severe temporomandibular joint (TMJ) pathology and degeneration experience high levels of pain in their daily lives and decreased range of mandibular movement. TMJ replacement is most often reserved for patients with end-stage TMJ disorders. Over the past few decades many advancements have been made in the types and materials used to replace the joint, and in turn have improved patients’ pain experience and daily function. Currently there are two categories of TMJ replacement prosthetics: stock prosthesis and custom prosthesis. When implanting the stock prosthesis, the surgeon must make the prosthesis fit at the time of surgery, while the custom prosthesis is made to fit the patient’s unique anatomy preoperatively. The model used to construct the custom prosthesis is extracted from a CT scan taken preoperatively. This makes the custom prosthesis more expensive and time consuming. To date, very little research has been done to directly compare the two categories of prosthesis. This study will systematically compare the stock TMJ prosthesis with the custom TMJ prosthesis, specifically looking at differences in functional outcomes and postoperative resolution of pain.
Methods: A systematic literature search (1960-2015) to identify eligible studies was completed using the PubMed, Web of Science and the Cochrane Library databases. The outcomes used to measure success of the TMJ replacement included postsurgical maximal incisal opening (MIO), and patient reported outcomes (PRO) such as pain and function. A random effects model will be used to calculate the weighted mean difference between the pre- and postoperative maximal incisal opening in both treatment groups.
Results: The search yielded 24 articles, nine of these articles met the inclusion criteria. The statistical analysis of the data is still pending at the time of abstract submission.
Conclusions: Preliminary analysis of the data suggests that while both stock and custom TMJ prosthesis increase IMO, the custom prosthesis allows for a greater increase in IMO than the stock prosthesis. The difference in PRO between stock and custom prosthesis is not significant. A more definitive conclusion will be made once statistical analysis is complete.