title: Comparison of intraoperative blood loss between four different surgical procedures in the treatment of bimaxillary protrusion.
abstract: OBJECTIVE
  This study was aimed at investigating the correlation between intraoperative blood loss and operation-related factors in the treatment of bimaxillary protrusion with four different procedures.
  
  
  METHODS
  Ninety-four patients were separated into the following four surgical groups: group 1: anterior subapical osteotomy of the maxilla (ASO Mx) + bilateral parasymphyseal osteotomy of the mandible (BPsO Md) + genioplasty (GeP); group 2: ASO Mx + BPsO Md; group 3: ASO Mx + ASO Md + GeP; and group 4: ASO Mx + ASO Md. Patient- and operation-related factors (age, intraoperative blood loss, operation time, and preoperative and postoperative blood parameters) were compared among the four groups.
  
  
  RESULTS
  The mean operation time and intraoperative blood loss were 438.7 minutes and 369.9 mL in group 1; 432.5 minutes and 356.5 mL in group 2; 393.3 minutes and 387.3 mL in group 3; and 353.5 minutes and 289.5 mL in group 4. Intergroup differences in intraoperative blood loss were not significant. A significant correlation between intraoperative blood loss and operation time was found in group 4 but not in the other groups.
  
  
  CONCLUSIONS
  No significant differences in blood loss were found among the four different surgical procedures in the treatment of bimaxillary protrusion.
authors.affiliation: School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors.forename: Yu-Chuan
authors.initials: YC
authors.lastname: Tseng
authors.affiliation: School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Chun-Chan
authors.initials: CC
authors.lastname: Ting
authors.affiliation: Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors.forename: Yu-Hsun
authors.initials: YH
authors.lastname: Kao
authors.affiliation: School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. Electronic address: Komschen@gmail.com.
authors.forename: Chun-Ming
authors.initials: CM
authors.lastname: Chen
mesh_terms: D000328:Adult; D016063:Blood Loss, Surgical; D001803:Blood Transfusion / Q000706:statistics & numerical data; D005260:Female; D063172:Genioplasty; D006801:Humans; D008297:Male; D008311:Malocclusion, Angle Class I / Q000601:surgery*; D063168:Mandibular Osteotomy; D063166:Maxillary Osteotomy; D016896:Treatment Outcome