Kocadereli Ilken, Yesil Turkan Nadire, Veske Pınar Sahin, Uysal Serdar
Professor and Head, Department of Orthodontics, Faculty of Dentistry, Hacettepe University, Ankara, Turkiye.
Eur J Dent. 2011 Jul;5(3):318-23.
The aim of this study was to determine the prevalence of apical root resorption in maxillary incisors during the initial stages of active orthodontic treatment and to test the hypothesis that root resorption increases with the progress of the treatment.
The study sample consisted of 80 teeth of 20 patients (14 female, 6 male) with a mean age of 14.9±2.8 years. Root resorption was determined with standardized digitized periapical radiographs. All the periapical radiographs were obtained at the beginning of orthodontic treatment (T0) and 3 months (T1), 6 months (T2) and 9 months (T3) after the beginning of the treatment by a paralleling device. They were digitalized as 600 dpi with a flatbed scanner and analyzed by software for image analysis at 400x magnification utilizing a personal computer.
All of the 4 maxillary incisors had an increasing amount of resorption during the 9-month period. The amount of root resorption between the time intervals was statistically significant (P<.05).
Root resorption of maxillary incisors can be detected in the early stages of orthodontic treatment and appears to be related to treatment duration. According to 9-month evaluation period, apical root resorption is of limited clinical significance for the average orthodontic patient.
本研究旨在确定在正畸治疗活动初始阶段上颌切牙牙根吸收的发生率，并检验牙根吸收随治疗进展而增加这一假设。
研究样本包括20例患者（14例女性，6例男性）的80颗牙齿，平均年龄为14.9±2.8岁。采用标准化数字化根尖片确定牙根吸收情况。所有根尖片均在正畸治疗开始时（T0）以及治疗开始后3个月（T1）、6个月（T2）和9个月（T3）时，使用平行投照装置获取。用平板扫描仪将其数字化为600 dpi，并通过个人计算机在400倍放大倍数下利用图像分析软件进行分析。
在9个月期间，所有4颗上颌切牙的吸收量均有所增加。各时间间隔之间的牙根吸收量具有统计学意义（P<0.05）。
上颌切牙的牙根吸收在正畸治疗早期即可检测到，且似乎与治疗持续时间有关。根据9个月的评估期，根尖牙根吸收对一般正畸患者的临床意义有限。
