利用迷你骨釘作為牙弓轉正之錨定裝置--病例報告

本病例報告為一成年女性，上顎骨前突，下顎骨後縮之骨性二級異常咬合，外突臉型側面觀，笑時嚴重露出齒齦（逾10mm），水平覆蓋16mm，垂直覆蓋2mm，上下前牙齒列擁擠，＃35、＃36、＃46缺失。治療計劃為正顎手術配合傳統齒列矯正，其方式為上顎拔兩顆第一小臼齒，以勒福氏一型骨切開術(Le Fort Ⅰ osteotomy)兩片式切割，將上顎骨向上壓入及後退，下顎自行向前上方旋轉並做頦骨整型術(genioplasty)，將下頦往前，＃44則自體移植至左下缺牙區成為＃35。手術治療後外觀獲得改善，但骨骼發生復位現象，上顎牙弓中線往右偏移4mm，水平覆蓋5mm，垂直覆蓋4mm，右側後牙錯咬。結果利用迷你骨釘作為錨定裝置，成功地將上顎牙弓往左側移動，並將前牙後退，改正右側後牙錯咬情形，得到很好的治療結果，因此，矯正用迷你骨釘不只可有效移動牙齒，也可旋轉牙弓。
This is a case of female adult patient with skeletal Class Ⅱ malocclusion. The problems of this case are as the followings: maxillary protrusion, mandibular retrusion, convex facial profile, gummy smile (>10mm), 16mm overjet, 2mm overbite, upper and lower anterior teeth crowding, and #35, #36, #46 missing. The treatment was performed by extraction of upper first premolar with traditional fixed orthodontic appliances combined with orthognathic surgery. The surgery method composed of LeFort Ⅰ two pieces osteotomy for maxillary intrusion and retraction, mandible autorotation forward and upward, and genioplasty for chin advancement. In addition, #44 was autotransplanted to the edentulous area of #35. The upper jaw relapse was noted after unwiring from interocclusal stent. The upper midline deviated to the right about 4mm, overjet increased to 5mm, overbite increased to 4mm, and right posteriors became crossbite. The mini-screws, then, were used as an anchorage to successfully move and rotate upper arch to the left, retract anterior teeth, and correct right posterior crossbite. In conclusion, orthodontic min-implants not only can correct teeth, but also move jaw dramatically.