Introduction: Compared to the classic maxilla-first sequence in bimaxillary orthognathic surgery, inverted mandible-sequence has been encouraged for potentially higher accuracy. However, evidence regarding this topic is lacking. Methods: A systematic review of the literature on different sequencing of bimaxillary surgery was conducted, gathering from following databases: Cochrane, Pubmed, Scopus, Medline (Ovid), Web of Science, ScienceDirect. Articles mentioning “sequencing”, “mandible-first”, “orthognathic surgery” of at least case-report level of evidence were included without restriction. Relevant articles were included for quality assessment and extracted data for indications of mandible-first sequence from all studies. Meta-analysis of surgical accuracy at upper central incisors in horizontal and vertical dimension was performed from included experimental studies. Results: The search of initially 619 articles resulted in 9 final articles: 6 case reports and 3 experimental studies. The four most commonly listed indications for mandible-first approach included instability of condylar centric relation (CR) position, posterior maxillary downgrafting, when rigid fixation of maxilla cannot be ascertained, and large maxillomandibular advancements. The pooled analysis of experimental studies composed of 188 patients (122 females, 66 males). Quality assessment of these studies resulted as moderate. Meta-analysis revealed no difference of surgical accuracy between both sequencing, with considerable heterogeneity. Conclusion: Mandible-first approach has been advocated under certain indications, in order to reduce potential jaw repositioning error and ease of surgical manipulation. Differences were not found in maxilla repositioning at central incisors, horizontally and vertically between both approaches. However, the results should be taken with caution because of heterogeneity in study design and outcome measurements.
Borikanphanitphaisan, Thatchawee and Ko, Ellen Wen-Ching
"Accuracy of Different Sequencing in Bimaxillary Orthognathic Surgery: A Systematic Review and Meta-analysis,"
Taiwanese Journal of Orthodontics: Vol. 31
, Article 2.
Available at: https://j.tjo.org.tw/tjo/vol31/iss1/2