Davidovitch M, McInnis D, Lindauer S J
Department of Orthodontics, School of Dentistry, Medical College of Virginia, Virginia Commonwealth University, Richmond, USA.
Am J Orthod Dentofacial Orthop. 1997 Jan;111(1):52-8. doi: 10.1016/s0889-5406(97)70302-0.
A prospective clinical trial was undertaken to study the effects of 6 months of continuous lip bumper therapy on patients in the mixed dentition with mild-to-moderate mandibular arch perimeter deficiency. Thirty-four patients, ages 7.9 to 13.1 years (mean = 10.2), seeking treatment in the postgraduate orthodontic clinic of the Medical College of Virginia, presented possessing 3 to 8 mm of mandibular crowding, with both mandibular primary second molars, were randomly placed in either the treatment or nontreatment group. Treated subjects underwent continuous lip bumper therapy, whereas the control subjects were monitored without undergoing any active treatment, each for 6 months. Arch dimension changes were assessed with study models. Alterations of mandibular incisor position were measured from lateral cephalometric radiographs. Mandibular left permanent first molar position changes were determined from both lateral cephalometric and tomographic radiographs, with the resolution of each imaging technique in measuring molar tooth movement also compared. It was found that significant differences in mandibular incisor inclination, molar position, arch length, and arch perimeter existed between treated and untreated subjects. In addition, multiple observer analysis showed that cephalometric examination lacks sensitivity when used to measure molar movement.
一项前瞻性临床试验开展，旨在研究连续6个月的唇挡治疗对处于混合牙列期、伴有轻至中度下颌牙弓周长不足患者的影响。34名年龄在7.9至13.1岁（平均10.2岁）、在弗吉尼亚医学院研究生正畸诊所寻求治疗、存在3至8毫米下颌牙列拥挤且双侧下颌乳第二磨牙均有的患者，被随机分为治疗组或非治疗组。治疗组患者接受连续唇挡治疗，而对照组患者不接受任何积极治疗，两组均观察6个月。通过研究模型评估牙弓尺寸变化。从头颅侧位片测量下颌切牙位置的改变。通过头颅侧位片和断层片确定下颌左侧第一恒磨牙位置的变化，并比较每种成像技术在测量磨牙移动方面的分辨率。结果发现，治疗组和未治疗组患者在以下方面存在显著差异：下颌切牙倾斜度、磨牙位置、牙弓长度和牙弓周长。此外，多观察者分析表明，当用于测量磨牙移动时，头颅测量检查缺乏敏感性。
