title: Presence of impacted teeth as a determining factor of unfavorable splits in 1256 sagittal-split osteotomies.
abstract: OBJECTIVE
  The purpose of this study was to determine the incidence of unfavorable mandibular fracture in sagittal-split osteotomies in the presence or absence of impacted third molar teeth.
  
  
  METHODS
  This retrospective study evaluated 1256 mandibular sagittal-split osteotomies in two groups of patients: Group I had impacted third molar teeth removed during sagittal-split osteotomy; in Group II, the third molar teeth had been removed at least 6 months before the sagittal-split osteotomy. Statistical testing consisted of chi-square analysis of contingency table for p < 0.05.
  
  
  RESULTS
  In 1256 mandibular sagittal-split osteotomies there were 24 (1.9%) with unfavorable fractures. Five of 24 occurred when third molar teeth were removed at the time of osteotomy and 19 of 24 mandibular fractures occurred when no impacted third molar tooth was present at the time of osteotomy. However, no significant difference was demonstrated between the groups.
  
  
  CONCLUSIONS
  The result of this study suggests that mandibular fractures may occur with greater frequency when the impacted third molar teeth have been removed at least 6 months before sagittal-split osteotomy as compared with that when third molar teeth are removed concomitant with sagittal-split osteotomy.
authors.affiliation: Department of Oral and Maxillofacial Sciences, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: D S
authors.initials: DS
authors.lastname: Precious
authors.forename: K E
authors.initials: KE
authors.lastname: Lung
authors.forename: B R
authors.initials: BR
authors.lastname: Pynn
authors.forename: R H
authors.initials: RH
authors.lastname: Goodday
mesh_terms: D000293:Adolescent; D000328:Adult; D016009:Chi-Square Distribution; D002648:Child; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008334:Mandible / Q000601:surgery*; D008337:Mandibular Fractures / Q000145:classification / Q000209:etiology*; D008875:Middle Aged; D008964:Molar, Third / Q000473:pathology*; D010027:Osteotomy / Q000009:adverse effects* / Q000379:methods; D012189:Retrospective Studies; D013997:Time Factors; D014081:Tooth Extraction; D014095:Tooth, Impacted / Q000150:complications*; D016896:Treatment Outcome