title: Accuracy of perioperative mandibular positions in orthognathic surgery.
abstract: Mandibular position is an important parameter used for the diagnosis of dentofacial deformities, as well as for orthognathic surgery planning and execution. Centric relation (anterior and superior relationship of the mandibular condyles interposed by the thinnest portion of their disks against the articular eminencies), centric occlusion (when lower teeth contact upper teeth at centric relation), and maximal intercuspation (complete interdigitation of lower and upper teeth) are not often addressed as factors that influence the results of orthognathic surgery, although these relationships are critical to ensure accuracy during the surgery. The present study assessed occlusal measurements taken before and after the induction of general anaesthesia from consecutive orthognathic surgery subjects. The variables assessed included the differences between these occlusal measurements, patient age, gender, type of deformity, and type of proposed orthognathic surgical procedure. The results demonstrated statistically significant differences for mandibular retrusion from maximal intercuspation to centric occlusion position, whereas the mandible appeared not to change significantly from centric occlusion after the induction of general anaesthesia. Patient age and the type of deformity appeared to influence the results. While in most instances centric occlusion can be adequately reproduced under general anaesthesia, for some specific orthognathic cases more accurate results might be obtained if the mandible-first sequence is used.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Sao Paulo - USP, Sao Paulo, Brazil; Post-Graduate Department, Faculty of Dentistry, University of Cuiabá - UNIC, Brazil. Electronic address: alex80@terra.com.br.
authors.forename: A M
authors.initials: AM
authors.lastname: Borba
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Sao Paulo - USP, Sao Paulo, Brazil.
authors.forename: O
authors.initials: O
authors.lastname: Ribeiro-Junior
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Sao Paulo - USP, Sao Paulo, Brazil.
authors.forename: M A
authors.initials: MA
authors.lastname: Brozoski
authors.affiliation: Post-Graduate Department, Faculty of Dentistry, University of Cuiabá - UNIC, Brazil.
authors.forename: P S
authors.initials: PS
authors.lastname: Cé
authors.affiliation: Department of Statistics, Institute of Exact and Earth Sciences, Federal University of Mato Grosso - UFMT, Brazil.
authors.forename: M M
authors.initials: MM
authors.lastname: Espinosa
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Sao Paulo - USP, Sao Paulo, Brazil.
authors.forename: M C Z
authors.initials: MC
authors.lastname: Deboni
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Illinois, Chicago, IL, USA.
authors.forename: M
authors.initials: M
authors.lastname: Miloro
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Sao Paulo - USP, Sao Paulo, Brazil.
authors.forename: M G
authors.initials: MG
authors.lastname: Naclério-Homem
mesh_terms: D000328:Adult; D003768:Dental Occlusion, Centric; D005260:Female; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000601:surgery*; D008334:Mandible / Q000002:abnormalities* / Q000601:surgery*; D008437:Maxilla / Q000002:abnormalities / Q000601:surgery; D008875:Middle Aged; D003765:Models, Dental; D056948:Orthognathic Surgical Procedures; D011446:Prospective Studies
keywords: centric dental occlusion; dental occlusion; dentofacial deformities; orthognathic surgery