Effectiveness of anterior repositioning splint versus other occlusal splints in the management of temporomandibular joint disc displacement with reduction: A meta-analysis

Background: Disc displacement with reduction (DDwR) is among the common disc disorders of temporomandibular joint (TMJ), which can be managed conservatively by splint therapy. Anterior repositioning splint (ARS) is the most commonly prescribed splint by dental practitioners, but not getting a normal disc–condyle relationship always and other side effects lead to need of comparing with other occlusal splints. This review will help in informed decision-making by clinicians in choosing an appropriate splint type for patients. Aim: The aim is to compare the effectiveness of ARS in the management of DDwR with other occlusal splints for TMJ and muscle pain, TMJ noise, any adverse effects, regaining normal disc–condyle relationship. Materials and Methods: We followed published protocol in the International prospective register of systematic reviews. Databases were searched till May 2023 using different search strategies as per the database. Title and abstract screening, followed by full-text screening and data extraction with risk of bias, was done by two independent reviewers in Covidence. Outcomes were reported as risk ratio (RR) or mean difference (MD) for dichotomous or continuous outcomes, respectively, using RevMan 5.4 (Review Manager 5.4) software. We used a random effect model for statistical analysis. Certainty of evidence was assessed using the Grading of Recommendation, Assessment, Development, and Evaluation Guideline Development Tool (GRADEpro GDT) software. Results: A total of 1145 reports were found from a database search. After screening, four studies were included for systematic reviews. Other occlusal splints reported were sagittal vertical extrusion device and mandibular ARS, full hard stabilization splint of canine or centric stabilization type. Data of only two studies could be used for meta-analysis having 30 participants received ARS and 40 received other occlusal splints. We did not find evidence of any difference between ARS and other occlusal splints for TMJ clicking in short term (RR 1.25, 95% confidence interval [CI] 0.91-1.72) but a small difference in favor of other occlusal splint in long term (RR 2.40, 95% CI 1.04–5.55). No evidence of any difference was found between both treatments for TMJ pain in short term (MD-5.68, 95% CI-17.31–5.95) and long term (MD 0.00, 95% CI-2.86–2.86) and muscle pain in short term. The certainty of evidence for comparison of two treatments for different outcomes was of low or very low level. Conclusion: Evidence is uncertain that other occlusal splints reduced TMJ clicking slightly in comparison to ARS. For the remaining outcomes, no evidence of any difference was found between the two splints and it may be biased due to selection bias, inadequate blinding of participants, and outcome assessor.