Postoperative changes in the position of anterior nasal spine and A-point after Le Fort I osteotomy. Issue 6 (November 2015)

• Record Type: Journal Article
• Authors: Fujinami, Hisashi; Kuroyanagi, Norio; Kamiya, Noboru; Miyachi, Hitoshi; Ozawa, Yoko; Ochiai, Shigeki; Nagao, Toru
• Is Part Of: Journal of oral and maxillofacial surgery, medicine, and pathology. Volume 27:Issue 6(2015)
• Page Start: 775
• Page End: 781
• Publication Date: 2015-11
• Subjects: Orthognathic surgery -- Le Fort I osteotomy -- Anterior nasal supine -- 3D-CT superimposition -- Postoperative changes; Mouth -- Surgery -- Periodicals; Face -- Surgery -- Periodicals; Maxilla -- Surgery -- Periodicals; Oral medicine -- Periodicals; Mouth -- Diseases -- Pathogenesis -- Periodicals; Surgery, Oral -- Periodicals; Oral Medicine -- Periodicals; Pathology, Oral -- Periodicals; Face -- Surgery; Maxilla -- Surgery; Mouth -- Diseases -- Pathogenesis; Mouth -- Surgery; Oral medicine; Electronic journals -- Sciences; Electronic journals -- Medicine; Periodicals; 617.522059
• DOI: 10.1016/j.ajoms.2015.04.003
• Languages: English
• ISSNs: 2212-5566

Abstract

Abstract: Purpose: This study focused on the postoperative changes in the position of the anterior nasal spine (ANS) and A-point after Le Fort I osteotomy (LFI). Materials and methods: Thirty-two patients underwent LFI, and cephalograms and computed tomography (CT) images were taken to assess skeletal changes immediately (T1) and 1 year (T2) postoperatively. In each cephalogram and 3D-CT analysis, changes in the coordinates ( X, Y, Z ) of the A-point, ANS, and PNS were evaluated between the T1 and T2 periods. Results: 3D-CT analyses demonstrated a significant difference in the identification of the Y -coordinate of ANS: 89.2 ± 4.1 mm in T1 and 87.0 ± 3.6 mm in T2 ( P = 0.04). The median of Y -coordinates of ANS on 3D-CT was 2.0 mm backward (range 0.44–7.3 mm). No significant differences were identified in SNA on conventional cephalometric analysis. Both 3D-CT and conventional cephalometric analyses showed that no significant differences were identified in PNS between the T1 and T2 periods. Conclusion: ANS tends to move backward after LFI, while the A-point tended to simultaneously move backward and downward. 3D-CT superimposition is more precise than conventional cephalograms in consideration of changes in the positions of ANS and the A-point for the evaluation of surgical stability after LFI. It may be possible to improve the reliability of 3D-CT and cephalometric analyses for determining maxillary bone stability by considering that ANS and the A-point tend to move backward and PNS is a more reliable reference point than ANS and the A-point after LFI.