Three dimensional accuracy and stability of segmented Le Fort I osteotomy - a systematic review

Segmental Le Fort I osteotomy has traditionally been regarded as less predictable and stable, a perception largely based on two-dimensional evaluation methods. Despite existing systematic reviews on clinical outcomes, a dedicated synthesis of three-dimensional assessments of surgical accuracy and postoperative stability is lacking.

This systematic review evaluated three-dimensional (3D) assessment methods and outcome of planning accuracy and postoperative stability in segmented Le Fort I osteotomies. The aim was to determine the reliability of 3D methods in capturing surgical accuracy and long-term skeletal stability.

Medline, Embase, Web of Science, and Cochrane were searched up to October 25, 2024. Eligible studies included randomized controlled trials, prospective or retrospective studies, or case series with > 5 patients reporting 3D evaluation of planning accuracy or stability. Exclusion criteria were systematic reviews, meta-analyses, single case reports, ex-vivo or animal studies, and studies involving syndromic patients, facial trauma, or prior maxillofacial surgery. Risk of bias and quality of evidence were assessed using the GRADE approach. Twenty-two studies met inclusion criteria: three randomized and nineteen non-randomized controlled trials. Fourteen assessed planning accuracy, five evaluated stability, and three examined both.

Twenty-two studies met the inclusion criteria and were included in the qualitative synthesis. Considerable methodological heterogeneity limited direct comparison and precluded meta-analysis. Overall, segmented Le Fort I osteotomy demonstrated clinically acceptable accuracy; however, certain movements-particularly transverse widening, advancement, and pitch-were more prone to underachievement, with discrepancies ranging from 0.77 to 1.41 mm, 0.55 to 2.69 mm, and 0.12° to 5.22°, respectively. During follow-up, transverse relapse was more pronounced at the dental level (0.39-1.41 mm) compared to skeletal changes (0.05-0.86 mm).

Segmented Le Fort I osteotomy shows reliable outcomes in 3D evaluations, but some maxillary movements remain difficult to achieve and maintain such as advancement and pitch. Standardized, voxel-based 3D assessment protocols are recommended to improve comparability and strengthen the evidence base. (PROSPERO registration: CRD42018111854).