Kretschmer Winfried Bernhard, Baciut Grigore, Baciut Mihaela, Zoder Werner, Wangerin Konrad
Department of Oral and Maxillofacial Surgery, Marienhospital Stuttgart, Stuttgart, Germany.
J Oral Maxillofac Surg. 2011 Mar;69(3):861-9. doi: 10.1016/j.joms.2010.05.024. Epub 2010 Nov 2.
The transverse dentoalveolar and skeletal stability of multipiece Le Fort I osteotomies with 3 different techniques was investigated.
The records of 87 patients undergoing bimaxillary osteotomies with 3-piece Le Fort I osteotomy were evaluated. According to the surgical technique of maxillary expansion, the subjects were divided into 3 groups: unilateral palatal osteotomy (group A), bilateral palatal osteotomy (group B), and unilateral palatal osteotomy with fixation of the palatal vault with a resorbable plate (group C). In group A palatal bone grafts were used in 9 patients. Posterior-anterior cephalograms and dental casts were taken before surgery (T1), immediately after surgery (T2), and after a follow-up of 12 to 15 months (T3). The skeletal base was measured between the intersections of the lateral contour of the maxillary alveolar process and the lower contour of the maxillo-zygomatic process. Dentoalveolar width was measured between the first premolars and the first molars. According to the magnitude of expansion, the groups were divided into the following subgroups: negative (constriction), 0 to 2 mm, greater than 2 mm to 4 mm, and greater than 4 mm. An analysis of variance with Bonferroni correction was used to compare the demographic and treatment characteristics and the surgical and postsurgical transverse movements of the 3 study groups. The paired t test was run to evaluate the surgical changes (T2 - T1) and the postsurgical stability (T3 - T2). The influence of palatal bone grafts and downgrafting of the maxilla on the amount of relapse was investigated with the unpaired t test.
The study variables (T1), the surgical changes (T2 - T1), and the postsurgical changes (T3 - T2) showed no significant differences between the 3 study groups. However, a tendency for less relapse in cases with major expansion was seen in group C. The mean expansion of the entire sample was 2.13 mm at the skeletal base, 1.11 mm in the premolar region, and 1.99 mm in the molar region. Mean relapses of 0.20 mm (9%) at the skeletal base, 0.76 mm (68%) in the premolar region, and 1.20 mm (60%) in the molar region were seen. Palatal bone grafts had no significant effect on the postsurgical changes in group A. Anterior and posterior downgrafting did not result in significantly more relapse.
Surgical expansion of the maxilla provides stable results at the maxillary skeletal base but high relapse rates in the dentoalveolar area. Preoperative orthodontic expansion is one of the main sources of transverse relapse. Fixation of the palatal vault with resorbable plates is a possible technique to improve transverse stability. Larger samples are necessary to provide statistical significance.
研究采用3种不同技术的多片段Le Fort I截骨术的横向牙槽骨和骨骼稳定性。
对87例行三段式Le Fort I截骨术的双颌截骨术患者的记录进行评估。根据上颌扩弓的手术技术，将受试者分为3组：单侧腭部截骨术（A组）、双侧腭部截骨术（B组）和用可吸收板固定腭穹窿的单侧腭部截骨术（C组）。A组中有9例患者使用了腭骨移植。在手术前（T1）、手术后即刻（T2）以及随访12至15个月后（T3）拍摄头颅后前位片和牙模。在上颌牙槽突外侧轮廓与上颌颧骨突下轮廓的交点之间测量骨骼基底。在第一前磨牙和第一磨牙之间测量牙槽骨宽度。根据扩弓幅度，将各组再分为以下亚组：负向（缩窄），0至2mm，大于2mm至4mm，以及大于4mm。采用Bonferroni校正的方差分析来比较3个研究组的人口统计学和治疗特征以及手术中和手术后的横向移动情况。采用配对t检验来评估手术变化（T2 - T1）和术后稳定性（T3 - T2）。采用非配对t检验研究腭骨移植和上颌骨向下植骨对复发量的影响。
3个研究组之间的研究变量（T1）、手术变化（T2 - T1）和术后变化（T3 - T2）均无显著差异。然而，C组中扩弓幅度较大的病例复发倾向较小。整个样本在骨骼基底的平均扩弓为2.13mm，在前磨牙区为1.11mm，在磨牙区为1.99mm。在骨骼基底的平均复发为0.20mm（9%），在前磨牙区为0.76mm（68%），在磨牙区为1.20mm（60%）。腭骨移植对A组的术后变化没有显著影响。前后向下植骨并未导致明显更多的复发。
上颌骨手术扩弓在上颌骨骼基底可提供稳定的结果，但在牙槽骨区域复发率较高。术前正畸扩弓是横向复发的主要来源之一。用可吸收板固定腭穹窿是一种可能改善横向稳定性的技术。需要更大的样本量以提供统计学意义。
