SINGLE VS. BIMAXILLARY SURGERY FOR CLASS III MALOCCLUSION: A SYSTEMATIC REVIEW OF OUTCOMES

Abstract

Background: Skeletal Class III malocclusion presents complex functional and aesthetic challenges, often requiring orthognathic surgery. Single-jaw surgery (mandibular setback or maxillary advancement) and bimaxillary procedures are widely used, yet their long-term skeletal stability, occlusal outcomes, airway changes, and patient satisfaction remain variably reported.

Objective: To systematically review the literature comparing postoperative stability and outcomes of single-jaw versus bimaxillary orthognathic surgery in adult patients with skeletal Class III malocclusion.

Methods: A systematic review was conducted following PRISMA 2020 guidelines. PubMed, Scopus, Web of Science, Embase, and Google Scholar were searched from inception to December 2025. Studies comparing single- versus two-jaw surgery in adult Class III patients, reporting cephalometric, 3D, or clinical outcomes, were included. Eleven studies met inclusion criteria, comprising prospective, retrospective, and long-term observational designs. Data on skeletal relapse, angular changes, airway dimensions, occlusal outcomes, and patient-reported satisfaction were extracted and narratively synthesised.

Results: Bimaxillary surgery generally provided superior horizontal skeletal stability and preserved airway dimensions compared to single-jaw procedures. Single-jaw mandibular setbacks occasionally demonstrated long-term mandibular positional stability but were more prone to occlusal relapse. Patient satisfaction was consistently high across both procedures (85–92%), with common postoperative concerns including altered facial sensation and airway narrowing. Surgery-first and minipreparation approaches were effective but required careful case selection for severe malocclusions.

Conclusion: Bimaxillary surgery is more effective in minimising horizontal relapse, maintaining airway integrity, and achieving optimal aesthetic and occlusal outcomes. Single-jaw surgery remains appropriate for select mild cases but carries a higher risk of relapse. Further standardised studies with long-term follow-up are warranted to optimise surgical planning and outcomes.