School of Stomatology, Capital Medical University, Beijing, China.
Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China.
Am J Orthod Dentofacial Orthop. 2024 Jan;165(1):80-92.e4. doi: 10.1016/j.ajodo.2023.07.014. Epub 2023 Sep 16.
Facial esthetics have always received much attention in orthodontic treatment, especially in young adult female patients. Three-dimensional (3D) soft-tissue changes after orthodontic extraction have not been fully explained. This study evaluated the 3D morphologic changes after orthodontic extraction in young female patients using a structured light scanner.
Forty-five adult female patients aged 20-25 years were enrolled in our study. The treatment group consisted of patients who received orthodontic treatment with 4 premolar extractions, and the control group was composed of young female volunteers who had not undergone any orthodontic treatment. To monitor the soft-tissue changes, 9 morphologic regions and 12 landmarks were identified for the 3D deviation analyses. The spatial deviations of landmarks and regions in the x, y, and z directions were constructed for quantitative analysis. Color map images were constructed to visualize soft-tissue displacement as a qualitative evaluation. The paired sample test was used to compare differences at the beginning of the experiment (T0) and after 24 months (T1) in both groups. An independent t test with Bonferroni correction was performed to compare differences between the treatment and control groups. A linear regression test was performed between incisor retraction and changes in the perioral tissues.
Subtracting the effect of aging from the lip changes in the control group, the treatment group showed a statistically significant difference in the displacement of labrale superius (-1.37 mm), labrale inferius (-1.89 mm), the upper lip region (-0.98 mm), and the lower lip region (-1.36 mm) along the z-axis. No significant differences were found between the treatment and control groups in the temporal, parotideomasseteric, and buccal regions. Pearson correlation tests indicated a positive correlation between incisor tip retraction and changes in soft tissues (two-dimensional cephalometric analysis, 3D landmark measurements, and 3D regional measurements). The correlation coefficient ranged between 0.45 and 0.55.
Three-dimensional soft-tissue changes were mainly concentrated in the upper and lower lip regions in adult female patients after the 4 premolars were extracted. For female patients aged 20-25 years with 4 extracted premolars, soft-tissue changes in the temporal, parotideomasseteric, and buccal regions were not clinically significant.
面部美学在正畸治疗中一直备受关注，尤其是在年轻成年女性患者中。正畸拔牙后三维（3D）软组织变化尚未得到充分解释。本研究使用结构光扫描仪评估了正畸拔牙后年轻女性患者的 3D 形态变化。
本研究纳入了 45 名 20-25 岁的成年女性患者。治疗组由接受正畸治疗拔除 4 颗前磨牙的患者组成，对照组由未接受任何正畸治疗的年轻女性志愿者组成。为了监测软组织变化，确定了 9 个形态区域和 12 个标志点进行 3D 偏差分析。构建了标志点和区域在 x、y 和 z 方向的空间偏差，进行定量分析。构建彩色地图图像以可视化软组织位移，作为定性评估。采用配对样本 t 检验比较两组患者实验开始时（T0）和 24 个月时（T1）的差异。采用独立 t 检验和 Bonferroni 校正比较治疗组和对照组之间的差异。对切牙内收与口周组织变化之间进行线性回归检验。
从对照组的唇部变化中减去衰老的影响，治疗组在唇上嵴（labrale superius）（-1.37mm）、唇下嵴（labrale inferius）（-1.89mm）、上唇区域（-0.98mm）和下唇区域（-1.36mm）沿 z 轴的位移方面表现出统计学上的显著差异。治疗组和对照组在颞区、腮腺咬肌区和颊区之间无显著差异。Pearson 相关检验表明，切牙尖端内收与软组织变化之间存在正相关（二维头影测量分析、3D 标志点测量和 3D 区域测量）。相关系数范围在 0.45 到 0.55 之间。
成年女性患者拔除 4 颗前磨牙后，3D 软组织变化主要集中在上唇和下唇区域。对于 20-25 岁接受 4 颗前磨牙拔除的女性患者，颞区、腮腺咬肌区和颊区的软组织变化无临床意义。
