Orthodontic Graduate Student, Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, SP, Brazil.
Angle Orthod. 2013 Mar;83(2):319-26. doi: 10.2319/042312-339.1. Epub 2012 Aug 14.
To evaluate the dentoskeletal changes of Class II malocclusion treatment with the Twin Force Bite Corrector (TFBC).
The sample comprised 86 lateral cephalograms obtained from 43 subjects with Class II division 1 malocclusion; the subjects were divided into two groups. The experimental group comprised 23 patients with a mean initial age of 12.11 years who were treated with the TFBC for a mean period of 2.19 years. The control group included 40 lateral cephalograms from 20 Class II nontreated patients, with an initial mean age of 12.55 years and a mean observation period of 2.19 years. The lateral cephalograms were evaluated before and after orthodontic treatment in group 1 and in the beginning and end of the observation period in group 2. t-Tests were used to compare the initial and final cephalometric characteristics of the groups as well as the amount of change.
The experimental group presented greater maxillary growth restriction and mandibular retrusion than the control group, as well as greater maxillomandibular relationship improvement and greater labial tipping of the mandibular incisors. The results also showed a greater decrease in overbite and overjet in the experimental group, and there were no statistically significant differences in the craniofacial growth pattern between groups.
The TFBC promotes restriction of anterior maxillary displacement without significant changes in mandibular length and position and improvement of maxillomandibular relationship without changes in facial growth and significant buccal tipping of mandibular incisors. Class II correction with the TFBC occurred primarily as a result of dentoalveolar changes.
评估 Twin Force Bite Corrector（TFBC）治疗安氏Ⅱ类错（牙合）的牙颌面变化。
本研究纳入了 86 例来自 43 名安氏Ⅱ类 1 分类错（牙合）患者的侧位头颅侧位片，将患者分为两组。实验组 23 例，平均初始年龄为 12.11 岁，使用 TFBC 治疗，平均治疗时间为 2.19 年。对照组包括 20 例未经治疗的安氏Ⅱ类错（牙合）患者的 40 例侧位头颅侧位片，平均初始年龄为 12.55 岁，平均观察时间为 2.19 年。实验组在正畸治疗前后和对照组在观察开始和结束时进行侧位头颅侧位片评估。使用 t 检验比较两组的初始和最终头影测量特征以及变化量。
实验组的上颌生长受限和下颌后缩程度大于对照组，同时上颌下颌关系改善和下颌切牙唇倾程度也更大。结果还显示实验组的覆（牙合）和覆盖减小程度更大，但两组的颅面生长模式无统计学差异。
TFBC 可促进上颌前牙位置的限制，而不显著改变下颌长度和位置，改善上颌下颌关系，不改变面型生长，下颌切牙显著唇倾。TFBC 治疗安氏Ⅱ类错（牙合）主要是由于牙颌变化引起的。
