title: Three-dimensional analysis of maxillary stability after Le Fort I osteotomy using hydroxyapatite/poly-L-lactide plate.
abstract: OBJECTIVE
  To evaluate three-dimensional change in maxillary position using biodegradable plates.
  
  
  METHODS
  A total of 53 patients who underwent orthognathic surgery using biodegradable plates were analyzed retrospectively. The position of maxilla was measured three-dimensionally using cone beam computed tomography data at preoperative (T0), 1-month postoperative (T1), and 1-year postoperative (T2) time points. Changes in the maxilla 1 year after the operation (T2-T1) were analyzed to demonstrate postoperative stability. The correlation between postoperative relapse (T2-T1) and surgical movement (T1-T0) of the maxilla was investigated.
  
  
  RESULTS
  At 1-year postoperatively, no significant changes in maxillary position were noted in the antero-posterior and transverse dimensions. The anterior maxillary position in the vertical dimension also showed no significant changes, but the posterior maxillary position (posterior nasal spine, greater palatine foramen) showed a 0- to 2.98-mm relapse at 1-year postoperatively. The posterior maxilla tended to relapse inferiorly when the amount of surgical upward movement was greater than 3-3.5 mm and to relapse superiorly when the amount of surgical upward movement was less than 3-3.5 mm. For all patients, no postoperative complications in the osteofixated maxilla were observed during the follow-up period.
  
  
  CONCLUSIONS
  Maxilla fixed with biodegradable plates was stable in the antero-posterior and transverse and the vertical (anterior maxilla) dimensions. Posterior maxillary vertical relapse was clinically acceptable, but relapse patterns that relate to the amount of surgical upward movement should be considered for surgical treatment planning.
authors.affiliation: Department of Oral and Maxillofacial Surgery, College of Dentistry, Yonsei University, Seoul 120-752, South Korea.
authors.forename: Jung-Hyun
authors.initials: JH
authors.lastname: Park
authors.affiliation: Department of Oral and Maxillofacial Surgery, College of Dentistry, Yonsei University, Seoul 120-752, South Korea.
authors.forename: Minkyu
authors.initials: M
authors.lastname: Kim
authors.affiliation: Private Practice, Vienna, VA, USA; Former Resident Harvard Oral and Maxillofacial Surgery, Boston, MA, USA.
authors.forename: Sang Yoon
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Oral and Maxillofacial Surgery, College of Dentistry, Yonsei University, Seoul 120-752, South Korea.
authors.forename: Hwi-Dong
authors.initials: HD
authors.lastname: Jung
authors.affiliation: Department of Oral and Maxillofacial Surgery, College of Dentistry, Yonsei University, Seoul 120-752, South Korea. Electronic address: ysjoms@yuhs.ac.
authors.forename: Young-Soo
authors.initials: YS
authors.lastname: Jung
mesh_terms: D020341:Absorbable Implants; D001860:Bone Plates; D001863:Bone Screws; D002508:Cephalometry; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D008334:Mandible / Q000601:surgery; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery*; D019340:Osteotomy, Le Fort / Q000379:methods*; D011091:Polyesters; D011183:Postoperative Complications; D016896:Treatment Outcome
chemical_list: D011091:Polyesters; C033616:poly(lactide)
keywords: Biodegradable; Le Fort I osteotomy; Orthognathic surgery; Stability; Three-dimensional analysis