The effect of micro-osteoperforation (MOP) in molar distalization treatments: an exploratory systematic review and meta-analysis of RCTs

OBJECTIVE: Molar distalization is a therapeutic approach commonly used for treating Class II malocclusions. However, the extended duration of this treatment often leads to its replacement with alternative methods that offer shorter treatment times. Micro-osteoperforation (MOP) has been introduced as a technique aimed at accelerating tooth movement and reducing treatment duration. The purpose of this study is to evaluate the impact of MOP on molar distalization outcomes to provide evidence for its effective and safe use. SEARCH METHODS: A comprehensive search was conducted across multiple databases, including MEDLINE, Web of Science, EMBASE, Scopus, and Cochrane's CENTRAL, up to April 2024, without any language or date restrictions. SELECTION CRITERIA: Only randomized clinical trials (RCTs) that addressed the defined PICO question were included in the analysis. The risk of bias in the included studies was assessed using the Cochrane Risk of Bias 2.0 (RoB 2) tool. DATA COLLECTION AND ANALYSIS: Relevant data were extracted using custom-designed forms, and a random-effects inverse variance meta-analysis was performed to synthesize the results. The primary outcomes analyzed were the rate and amount of molar distalization, while secondary outcomes included pain levels, root resorption, and periodontal health. RESULTS: Four RCTs, involving a total of 71 participants, were included in this exploratory review. Most studies were at low or some concerns risk of bias. The meta-analysis revealed no significant differences in the rate or amount of molar distalization between the MOP and control groups (mean difference [MD] = 0.1 mm/month and 0.01 mm, respectively, P > .05). However, the MOP group reported significantly higher pain levels on the day of the procedure (MD = 2, P = .01) on a 10-point visual analog scale (VAS) compared to the control group. This difference in pain perception was no longer significant seven days after the procedure (MD = 0.52, P = .52). CONCLUSION: While MOP is associated with increased immediate postoperative pain, it does not significantly enhance the efficiency of molar distalization. Therefore, the use of MOP for distalization should be judiciously considered and reserved for cases that involve particularly challenging or prolonged movements, based on the specific needs and characteristics of each patient. Limitations of this review include the small number of available RCTs and variability in MOP protocols, which may limit the generalizability of the findings. REGISTRATION: The protocol for this systematic review was registered at PROSPERO with the ID CRD42024589482.