Accuracy of maxillary repositioning surgery in teaching hospitals using conventional model surgery

Amir Yari; Mahboube Hasheminasab; Amirali Badri; Behrad Tanbakuchi; Paniz Fasih

doi:10.1007/s10006-023-01174-2

Accuracy of maxillary repositioning surgery in teaching hospitals using conventional model surgery

Oral Maxillofac Surg. 2023 Jul 24. doi: 10.1007/s10006-023-01174-2. Online ahead of print.

Authors

Amir Yari¹, Mahboube Hasheminasab², Amirali Badri³, Behrad Tanbakuchi⁴, Paniz Fasih⁵

Affiliations

¹ Department of Oral and Maxillofacial Surgery, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. amir.yari@hotmail.com.
² Department of Orthodontics, Arthur Dugoni School of Dentistry, University of the Pacific, San Francisco, CA, USA.
³ Department of Oral and Maxillofacial Surgery, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
⁴ Department of Orthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
⁵ Department of Prosthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

PMID: 37486423
DOI: 10.1007/s10006-023-01174-2

Abstract

Purpose: The aim of this study was to assess the accuracy of maxillary repositioning surgery in teaching hospitals using conventional model surgery.

Materials and methods: A total of 73 patients undergoing single-piece LeFort I osteotomies in the maxilla and bilateral sagittal split osteotomies in the mandible were included in the study. Preoperative and immediate postoperative cone-beam CT were compared in computer software (Dolphin3D©). Maxillary landmarks relative to the vertical and horizontal reference lines were evaluated. The difference between the planned and achieved maxillary positions was measured. Distance error in millimeters and achievement ratio (achieved displacement/planned displacement*100) were calculated for different maxillary movements.

Results: Midline correction and advancement were the most accurate movements with an overall mean distance error of 0.53 mm and 0.63 mm respectively while posterior impaction and setback were the least accurate movements with 1.38 mm and 1.76 mm mean discrepancies, respectively. A significant difference was observed only in setback movement regarding the discrepancy value (P < .05). Although setback and down-graft movements tended to under-correction, all other movements were overcorrected. As the magnitude of maxillary movements increases, the accuracy decreases. In severe displacements (≥ 8 mm), the accuracy declines significantly (P < .05).

Conclusion: Classic cast surgery and manually fabricated intermediate splints in teaching hospitals yield accurate and acceptable results in the majority of cases (84.6%). The accuracy of maxillary repositioning decreases as the magnitude of displacement increases.

Keywords: Maxillary repositioning; Orthognathic surgery; Splint; Surgical accuracy; Two-jaw surgery.

Publication types

Letter