Dowling Paul A, Espeland Lisen, Sandvik Leiv, Mobarak Karim A, Hogevold Hans Erik
Department of Public and Child Dental Health, Trinity College, Dublin, Ireland.
Am J Orthod Dentofacial Orthop. 2005 Nov;128(5):560-7; quiz 669. doi: 10.1016/j.ajodo.2004.07.051.
The objectives of this retrospective cephalometric study were to assess the amount, direction, and timing of postoperative changes after LeFort I maxillary advancement, and to identify risk factors for skeletal relapse.
The material was selected from the files at the Department of Orthodontics, University of Oslo, and comprised 43 patients who underwent 1-piece LeFort I advancement as the only surgical procedure from 1990 to 1998. All patients were followed for 3 years by using a strict data collection protocol. Lateral cephalograms were obtained before surgery and at 5 times after surgery.
A mean relapse of 18% of the surgical advancement occurred. In 14% of the patients, clinically significant skeletal relapse (> or = 2 mm) was observed. Most (89%) postoperative change occurred during the first 6 months after surgery. Skeletal relapse increased significantly with degree of surgical advancement (P = .001) and degree of inferior repositioning of the anterior maxilla (P = .004) (linear regression analysis). At the end of follow-up, overjet and overbite were within clinically acceptable ranges for all patients.
Maxillary advancement with a 1-piece LeFort I osteotomy is a relatively stable procedure. Identified risk factors for horizontal relapse were degree of surgical advancement and degree of inferior repositioning of anterior maxilla.
本回顾性头影测量研究的目的是评估LeFort I型上颌骨前徙术后变化的量、方向和时间，并确定骨骼复发的危险因素。
材料选自奥斯陆大学正畸科档案，包括1990年至1998年期间接受单块LeFort I型前徙作为唯一外科手术的43例患者。所有患者均按照严格的数据收集方案随访3年。术前及术后5个时间点拍摄头颅侧位片。
手术前徙量平均复发18%。14%的患者观察到临床上显著的骨骼复发（≥2 mm）。大部分（89%）术后变化发生在术后前6个月。骨骼复发随手术前徙程度（P = .001）和上颌前部向下复位程度（P = .004）显著增加（线性回归分析）。随访结束时，所有患者的覆盖和覆合均在临床可接受范围内。
单块LeFort I型截骨术进行上颌前徙是一种相对稳定的手术。确定的水平复发危险因素为手术前徙程度和上颌前部向下复位程度。
