Reukers E A, Sanderink G C, Kuijpers-Jagtman A M, van't Hof M A
Department of Orthodontics and Oral Biology, University of Nijmegen, The Netherlands.
J Orofac Orthop. 1998;59(2):100-9. doi: 10.1007/BF01340644.
The purpose of this paper was to compare radiographically the prevalence and degree of apical root resorption after treatment with a fully programmed edgewise appliance (FPA) and a partly programmed edgewise appliance (PPA) in a randomized multipractice clinical trial. Two groups of patients with Class II malocclusions were treated orthodontically. The type of treatment was randomly assigned by a computer program. During fixed appliance therapy, one group was treated according to the precepts of the straight wire concept (FPA; n = 32) while the other was treated with conventional full edgewise mechanics (PPA; n = 29). Treatment times were recorded. Radiographs of the maxillary incisors were made before and after active treatment with fixed appliances using the bisecting angle technique. To correct for different projecting angles the pairs of radiographs were digitally reconstructed. The prevalence and degree of root resorption were assessed. The mean treatment time was 1.8 years and 1.6 years for treatment with FPA and PPA, respectively. The mean amount of loss of tooth length was 8.2% for the patients treated with FPA and 7.5% for the patients treated with PPA. No statistically significant differences could be assessed between both groups at the end of active treatment. The mean prevalence of apical root resorption was 75% for the patients treated with FPA and 55% for the patients treated with PPA. Statistical evaluation showed no significant differences. We concluded that the prevalence and degree of root resorption is independent of the appliances as used in this study.
本文的目的是在一项随机多机构临床试验中，通过影像学比较使用全程序方丝弓矫治器（FPA）和部分程序方丝弓矫治器（PPA）治疗后根尖吸收的发生率和程度。两组安氏II类错牙合患者接受正畸治疗。治疗类型由计算机程序随机分配。在固定矫治器治疗期间，一组按照直丝弓理念的原则进行治疗（FPA；n = 32），而另一组采用传统的全方丝弓矫治技术（PPA；n = 29）。记录治疗时间。使用分角线投照技术在固定矫治器主动治疗前后拍摄上颌切牙的X线片。为校正不同的投照角度，对成对的X线片进行数字重建。评估根尖吸收的发生率和程度。FPA组和PPA组的平均治疗时间分别为1.8年和1.6年。FPA组患者牙齿长度的平均减少量为8.2%，PPA组患者为7.5%。在主动治疗结束时，两组之间未评估到统计学上的显著差异。FPA组患者根尖吸收的平均发生率为75%，PPA组患者为55%。统计学评估显示无显著差异。我们得出结论，本研究中使用的矫治器与根尖吸收的发生率和程度无关。
