青少年女性月经周期不同阶段加力对正畸牙移动的影响

Orthodontic tooth movement at different stages of adolescent female menstrual cycle

背景:雌激素对正畸牙齿移动有影响,目前仅有动物实验证明,雌激素水平越低,正畸牙移动量越大,雌激素水平越高,正畸牙移动量越小。目的:分析青少年女性正畸患者月经周期的不同时期加力对正畸牙移动的影响。方法:选取12例14-18岁已具有月经初潮,月经规律,需要拔除上颌第1前磨牙的女性患者。采取自身对照,将患者上颌左右两侧尖牙,随机分为月经期加力组和排卵期加力组,应用种植体支抗加力远中移动尖牙,月经期加力组加力2周后排卵期加力组开始加力。各组分别于加力即刻及4周时取模,灌制超硬石膏模型,测量各组尖牙向远中移动的距离,采用GraphPad Prism5软件包对数据进行统计学分析。结果与结论:月经期加力组尖牙移动量大于排卵期加力组(P<0.05)。提示青少年女性正畸患者在月经期加力正畸牙的移动速度较排卵期正畸牙的移动速度显著增加,可有效缩短正畸矫治疗程。

BACKGROUND：Estrogen has an effect on orthodontic tooth movement. Currently, only animal experiments show that the lower estrogen levels, the greater the amount of orthodontic tooth movement;the higher estrogen levels are, the smal er the amount of orthodontic tooth movement is. OBJECTIVE：To investigate effects of orthodontic force applied on orthodontic tooth movement at different stages of menstrual cycle among young female patients. METHODS：Twelve young female patients were included in this study, aged 14-18 years old. They already have regular menstrual cycle, and need to extract the first premolar in the maxil a. By using self-control method, these female patients with their maxil ary canine at both sides were randomly divided into two groups：orthodontic force at ovulatory period and orthodontic force at menstrual period. Micro-implant anchorage was implanted to the distal y moving canine. Orthodontic force was given to the group of ovulatory period 2 weeks after the force was given at menstrual period. Dentition models were taken at day 0 and 28 after force, to prepare a superhard plaster model using silastic impression materials. Between these two groups, the distances of the canine distal movement were measured and statistical analysis was performed with GraphPad Prism5 software. RESULTS AND CONCLUSIONS：The distances of the canine distal movement in the group of orthodontic force at menstrual period were greater than that in the other group （P〈0.05）. The orthodontic teeth with the application of orthodontic force at menstrual period move faster than that with the application of orthodontic force at ovulatory period, thus effectively shortening orthodontic treatment.