title: Comparison of mandibular stability after SSRO with surgery-first approach versus conventional ortho-first approach.
abstract: METHODS
  Postoperative mandibular stability in the surgery-first (SF) approach and ortho-first (OF) approach in orthognathic surgery was retrospectively assessed using the lateral cephalo X-P in 38 patients with skeletal Angle Class III malocclusion who underwent sagittal split ramus osteotomy (SSRO).
  
  
  RESULTS
  The postoperative mandibular relapse of the two groups observed from T1 (2 weeks after the surgery) to T2 (for the OF group, a year after surgery; for the SF group, the day orthodontic treatment was completed) was compared. The mean (SD) horizontal relapse at pogonion was 0.86 (0.92) mm in the forward direction in the SF group and 0.90 (1.09) mm in the forward direction in the OF group. No significant difference was found in the amount of horizontal movement between the two groups. On the other hand, the mean (SD) vertical relapse at pogonion was 1.59 (2.91) mm in the downward direction in the SF group and 0.14 (1.30) mm in the upward direction in the OF group, showing a significant difference in the amount of movement between the two groups. The degree of completion of the occlusion at T2 in the SF group was compared with that in the OF group by measuring OB, OJ, L1-occlusal plane angle, and interincisal angle. No significant difference was found between the two groups and the post-treatment occlusion was clinically favourable.
  
  
  CONCLUSIONS
  Although the SF approach has several advantages for patients, the method of operation and fixation should be selected carefully to maintain postoperative mandibular stability.
authors: a Department of Plastic and Reconstructive Surgery , School of Medicine, Tokai University , Kanagawa , Japan and.
authors: Tadashi
authors: T
authors: Akamatsu
authors: a Department of Plastic and Reconstructive Surgery , School of Medicine, Tokai University , Kanagawa , Japan and.
authors: Ushio
authors: U
authors: Hanai
authors: a Department of Plastic and Reconstructive Surgery , School of Medicine, Tokai University , Kanagawa , Japan and.
authors: Muneo
authors: M
authors: Miyasaka
authors: b Shinwakai Medical Corporation, Ichikawa Orthodontic Office , Tokyo , Japan.
authors: Hiroyuki
authors: H
authors: Muramatsu
authors: b Shinwakai Medical Corporation, Ichikawa Orthodontic Office , Tokyo , Japan.
authors: Shou
authors: S
authors: Yamamoto
mesh_terms: D002508:Cephalometry; D006801:Humans; D008313:Malocclusion, Angle Class III / Q000601:surgery*; D008334:Mandible / Q000601:surgery; D056948:Orthognathic Surgical Procedures / Q000379:methods*; D059229:Osteotomy, Sagittal Split Ramus; D012189:Retrospective Studies
keywords: mandibular stability; orthognathic surgery; postoperative mandibular relapse; surgery-first