Can a unilateral total temporomandibular joint prosthesis affect the healthy contralateral temporomandibular joint? A systematic review

Temporomandibular joint (TMJ) prostheses are considered an important alternative for the treatment of severe end-stage TMJ disorders. However, unilateral TMJ replacement may affect the healthy contralateral TMJ. The purpose of this study was to systematically review the literature on the effects of unilateral total TMJ prosthesis placement on the contralateral healthy TMJ. The PubMed, Scopus, Web of Science, and Cochrane Library databases were searched for English- language articles published up to December 2023. Inclusion criteria encompassed clinical studies (randomized, prospective, retrospective, observational) that evaluated clinical and patient-reported outcomes after total unilateral TMJ prosthesis placement (both glenoid and mandibular components). The initial search identified 141 non-duplicate studies, of which eight remained after title and abstract reading. Four studies included only unilateral prostheses; the other four included bilateral interventions and/or control groups without any TMJ intervention. The studies reported on stock and custom prostheses, with custom prostheses being the most used. As the studies had different specific objectives, no pattern of data reporting was found and the research question could not be answered. Randomized clinical trials with standardized variables are required to achieve reliable conclusions. Furthermore, long-term follow-up is necessary to determine whether the function of the healthy TMJ is compromised.