馬蹄形骨切り術を併用した分割Le FortⅠ型骨切り術による上顎歯列弓拡大

Purpose: To assess the maxillary dental arch width expansion and postoperative stability of segmental Le Fort Ⅰ osteotomy combined with horseshoe osteotomy. Materials methods: Seventy consecutive cases that underwent during two years from January 2018 to December 2019, were examined retrospectively. Two （Group A）, parasagittal palatal B） additional C） performed relieve tension mucosa. evaluate expansions rates three groups, posteroanterior cephalograms employed before surgery immediately after surgery. The was measured as distance between left right outermost points arch. In addition, widths on plaster models group C surgery, at end orthodontic treatment, more than 1 year treatment. stabilities C, Wilcoxon signed-rank test used compare relapse treatment least Results: number in groups A, B 32, 29 9, respectively. mean values 2.3 （1.1-3.6）±0.6, 4.1 （2.9-5.4）±0.7 6.6 （4.8-8.8）±1.0mm; 3.4 （1.7-5.4）±0.8, 6.1 （4.0-8.0）±1.0 10.0 （8.2-14.4）±1.7％, 8 stages, 10.9 （−4.1 41.8）±14.9 15.1 （−13.3 35.6）±14.1％, No significant difference observed stages （p＝0.547）. Conclusion: group, 6mm or 8％ obtained posterior part maxilla good observed.