Evaluating Surgical Accuracy in Bimaxillary Surgery: A Systematic Review and Meta-Analysis of Mandible-First versus Maxilla-First Approaches.

Background: Mandible-first surgery (MdFS) has gained attention as an alternative to the traditional maxilla-first surgery (MxFS) in bimaxillary procedures. Given the distinct sequence of operations between these approaches, evaluating the clinical advantages of MdFS compared to MxFS is crucial for optimizing surgical decision-making. This systematic review and meta-analysis examine intraoperative achievability and postoperative stability between these two surgical approaches.

Methods: A thorough literature search was performed using PubMed, Embase, Web of Science, and MEDLINE, covering articles published from 2013 to 2023. Studies included were retrospective, prospective, and randomized trials that compared the accuracy and/or stability of MdFS with MxFS. The primary endpoint for the meta-analysis was the standardized mean difference in surgical accuracy for translational movements, with a secondary focus on rotational accuracy.

Results: A total of 11 studies encompassing 712 patients met the inclusion criteria. The analysis suggested that MdFS might reduce accuracy in the sagittal dimension (CI, 0.05 to 0.74) but offered greater achievability in the vertical direction (CI, - 0.47 to - 0.07). Additionally, MdFS was associated with a relatively posterior (CI, - 1.18 to - 0.60) and inferior (CI, - 0.64 to - 0.07) positioning of the maxillomandibular complex.

Conclusion: Despite certain limitations, our findings indicate that MdFS can achieve clinical outcomes similar to MxFS in terms of both accuracy and stability. However, further researches with larger sample sizes and more rigorous study designs are necessary to validate these conclusions.

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