Survival Rates of Reinserted Orthodontic Microimplants: An Exploratory Systematic Review

Background/Objectives: The loss of orthodontic microimplants is a common clinical complication that significantly disrupts the continuity of malocclusion treatment. Despite increasing clinical use of microimplant reinsertion, the factors influencing its success remain unclear. The aim of this exploratory systematic review was to examine the available literature regarding clinical outcomes related to the retention of orthodontic microimplants following their reinsertion. Methods: Studies that assessed the success of orthodontic microimplant reinserted were included in the review. Searches were conducted on 27 September 2025, in the following databases: BASE (Bielefeld Academic Search Engine), PubMed, Scopus, and EMBASE. The ROBINS-I (Risk of Bias in Non-randomized Studies—of Interventions) tool was used to assess the risk of bias. Due to heterogeneity of included studies, a narrative synthesis was performed. Results: Four of the 577 studies were included in the review. A total of 305 microimplants were reinserted in 276 patients. The overall success rate ranged from 44.16% to 66%. Analysis indicated a significantly higher success rate in the maxilla (up to 68.60%) compared to the mandible (lowest 36.84%). Furthermore, a narrative synthesis suggests better clinical outcomes for 8 mm long microimplants compared to 6 mm ones, as well as reduced reinsertion success in areas with high cancellous bone density. Regarding the modification of the insertion site, the current data are contradictory; while some studies indicate significant benefits from changing the site (e.g., to the midpalatal suture), others show no statistical difference compared to reinsertion at the same site. Overall, the evidence remains limited and heterogeneous. Conclusions: The current review of the literature on the success of reinsertion of orthodontic microimplants is subject to a high risk of misinterpretation, due to the limited amount of data and the risk of unidentified confounding factors. Further standardized clinical trials are needed to develop unified protocols for these procedures. Other: The review was prospectively registered with the Open Science Framework (OSF); osf.io/tbj2s.