非対称下顎前突症に対する矢状突起分割骨切り術、口腔内垂直突起骨切り術、外側皮質切除術

Sagittal split ramus osteotomy, intraoral vertical ramus osteotomy, and lateral corticectomy for asymmetric mandibular prognathism.

抄録

目的:

本研究の目的は、上顎にLeFort I骨切り術、下顎にsagittal split ramus osteotomy（SSRO）およびintraoral vertical ramus osteotomy（IVRO）を行い、IVRO側に外側皮質切除術を行った後の術後前後安定性および顔面非対称性の改善度を評価することであった。

OBJECTIVES: The purpose of this study was to evaluate the postoperative anteroposterior stability and improvements in facial asymmetry after performing LeFort I osteotomy in the maxilla, sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO) in the mandible, and lateral corticectomy on the IVRO side.

材料および方法:

2009年7月から2018年10月まで、11名の被験者に対してレトロスペクティブな解析を行った。術前（T0），術後（T1），12か月後のフォローアップ（T2）に側方セファロX線写真を実施し，B点距離を測定した。術前（S0）と術後12ヶ月（S1）に前方セファロX線写真を撮影し、顔面非対称性の5つの指標（Ag angle、M-Ag、Co-Ag、Co-Me、Ag-Me）を計測した。

MATERIALS AND METHODS: From July 2009 to October 2018, a retrospective analysis was performed on 11 subjects. Lateral cephalometric radiograph was performed preoperatively (T0), postoperatively (T1), and at 12 months of follow-up (T2), and the B point distance was measured. Posteroanterior cephalometric radiograph was performed preoperatively (S0) and at 12 months of follow-up (S1) and was used to measure five indicators (Ag angle, M-Ag, Co-Ag, Co-Me, and Ag-Me) of facial asymmetry.

結果:

T0とT1ではB点距離に有意差があったが（=0.007）、T1とT2では有意差はなかった（=0.1）。また、T2とT0のB点距離には有意差があった（=0.026）。顔面の非対称性指標を手術前後で比較すると、S0とS1ではすべての指標で有意差が認められた。Ag angleの-値は0.003、M-Ag、Co-Ag、Co-Me、Ag-Meは0.004であり、0.003、0.008、0.006、0.004だった。Z値は負のランクに基づくものであった。

RESULTS: The B point distances for T0 and T1 were significantly different (=0.007), whereas those for T1 and T2 were not significantly different (=0.1). In addition, there was a significant difference between the B point distances of T2 and T0 (=0.026). Comparison of the facial asymmetry indicators before and after surgery showed a significant difference for all indicators between S0 and S1: the -values of Ag angle, M-Ag, Co-Ag, Co-Me, and Ag-Me were 0.003, 0.003, 0.008, 0.006, and 0.004, respectively. The Z value was based on negative ranks.

結論:

術後から12ヶ月後のフォローアップまで、B点距離に有意差はなかった。しかし，顔の非対称性に関連する5つの指標すべてにおいて，術前と術後で有意な差が認められた。顔面の非対称性に関する5つの指標は、術後すべて数値が上昇した。

CONCLUSION: There was no significant difference in the B point distances from postoperation to the 12-month follow-up. However, there were significant differences in all five indicators related to facial asymmetry before and after surgery. The values for the five indicators of facial asymmetry all increased postoperatively.