Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, Brazil.
Eur J Orthod. 2012 Apr;34(2):182-7. doi: 10.1093/ejo/cjq182. Epub 2011 Mar 10.
The purpose of this study was to retrospectively compare the treatment times of Class II division 1 malocclusion subjects treated with four first premolar extractions or a non-extraction protocol and fixed edgewise appliances. Eighty-four patients were selected and divided into two groups. Group 1, treated with four first premolar extractions, consisted of 48 patients (27 males and 21 females) with a mean age of 13.03 years and group 2, treated without extractions, consisted of 36 patients (18 males and 18 females) with a mean age of 13.13 years. Group 2 was subdivided into two subgroups, 2A consisting of 16 patients treated in one phase and 2B consisting of 20 patients treated in two phases. The initial and final Treatment Priority Index (TPI), initial ages, initial mandibular crowding, and treatment times of groups 1 and 2 were compared with t-tests. These variables were also compared between group 1 and the subgroups with analysis of variance followed by Tukey's tests. The treatment times for groups 1 and 2 and subgroups 2A and 2B were 2.36, 2.47, 2.25, and 2.64 years, respectively, which were not significantly different. Treatment times with non-extraction and four premolar extraction protocols are similar.
本研究旨在回顾性比较使用四前磨牙拔牙或非拔牙方案和固定直丝弓矫治器治疗安氏Ⅱ类 1 分类错（牙合）的治疗时间。选择了 84 名患者，并将其分为两组。第 1 组（48 名患者，27 名男性和 21 名女性）接受四前磨牙拔牙治疗，平均年龄为 13.03 岁；第 2 组（36 名患者，18 名男性和 18 名女性）接受非拔牙治疗，平均年龄为 13.13 岁。第 2 组进一步分为 2A 组（16 名患者，一期治疗）和 2B 组（20 名患者，二期治疗）。比较了两组的初始和最终治疗优先指数（TPI）、初始年龄、初始下颌拥挤度和治疗时间。采用方差分析和 Tukey 检验比较第 1 组与亚组之间的这些变量。第 1 组和第 2 组以及第 2A 组和第 2B 组的治疗时间分别为 2.36 年、2.47 年、2.25 年和 2.64 年，差异无统计学意义。非拔牙和四前磨牙拔牙方案的治疗时间相似。
