Omar Ziad, Short Lesley, Banting David W, Saltaji Humam
Private practice, Mississauga, Ontario, Canada; Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
Noosa Heads, Queensland, Australia.
Int Orthod. 2018 Mar;16(1):91-104. doi: 10.1016/j.ortho.2018.01.017. Epub 2018 Feb 22.
To determine the change in the soft tissue profile following extraction orthodontic treatment with either first or second premolar extractions.
This was a retrospective clinical study of 81 consecutive orthodontic patients treated with extraction of four premolars. Patients were divided into two treatment groups according to whether four first premolar teeth (PM1 treatment group, n=48) or four second premolar teeth were removed (PM2 treatment group, n=33) during treatment. Changes in the nasolabial angle and the distance of the upper and lower lips to E-plane were compared pre- and post-treatment. Age, sex, upper lip thickness, facial convexity, facial axis, upper and lower arch crowding at pre-treatment, use of molar anchorage and the amount of retrusion of the maxillary and mandibular incisor teeth during treatment were used as explanatory variables.
When facial convexity and facial axis at pre-treatment, the use of maxillary anchorage and the amount of retrusion of the maxillary and mandibular incisor teeth achieved as a consequence of treatment were taken into account, there was less than one degree (0.67°) difference between the change in the nasolabial angle in the PM1 treatment group compared to the PM2 treatment group (P>0.05). The mean change in the upper lip position relative to E-plane and the mean change in lower lip position relative to E-plane were also similar for the two groups.
The change in soft tissue profile following orthodontic treatment was similar regardless of whether first premolar or second premolar teeth were removed.
确定拔除第一前磨牙或第二前磨牙的正畸拔牙治疗后软组织侧貌的变化。
这是一项对81例连续接受四颗前磨牙拔除正畸治疗患者的回顾性临床研究。根据治疗期间拔除的是四颗第一前磨牙（第一前磨牙治疗组，n = 48）还是四颗第二前磨牙（第二前磨牙治疗组，n = 33），将患者分为两个治疗组。比较治疗前后鼻唇角以及上、下唇至E平面距离的变化。将年龄、性别、上唇厚度、面部凸度、面部轴、治疗前的上、下牙弓拥挤情况、磨牙支抗的使用以及治疗期间上颌和下颌切牙的内收量用作解释变量。
当考虑治疗前的面部凸度和面部轴、上颌支抗的使用以及治疗后上颌和下颌切牙的内收量时，第一前磨牙治疗组与第二前磨牙治疗组的鼻唇角变化差异小于1度（0.67°）（P>0.05）。两组相对于E平面的上唇位置平均变化和相对于E平面的下唇位置平均变化也相似。
无论拔除的是第一前磨牙还是第二前磨牙，正畸治疗后的软组织侧貌变化相似。
