Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing, China.
National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China.
Orthod Craniofac Res. 2024 Dec;27(6):985-995. doi: 10.1111/ocr.12842. Epub 2024 Aug 13.
This study aims to compare the achieved and predicted root movements in adults after four first-premolar extractions and Invisalign treatment.
Thirty-three consecutive adults (22 Class I, 9 Cusp-to-cusp Class II and 2 Cusp-to-cusp Class III) from a single clinical division who completed the first series of aligners after premolar extractions were included in this retrospective study. A pretreatment cone-beam computed tomography model was registered onto the pretreatment surface-scanned dental model (SSDM) to locate the pretreatment root apices of the whole dentition. These were copied and transferred to the predicted and achieved post-treatment SSDMs to acquire the locations of the predicted and achieved post-treatment root apices. The differences between predicted and achieved root movements (DPARMs) were tested using the paired t-test or Wilcoxon signed rank test.
In the anteroposterior direction, posterior root movements of maxillary and mandibular anterior teeth were poorly achieved (3.24-5.74 mm DPARMs, p < .05). In the vertical direction, roots of maxillary anterior teeth achieved greater intrusion (0.70-0.93 mm DPARMs, p < .05), while those of mandibular incisors achieved less intrusion (0.57-0.65 mm DPARMs, p < .05) than predicted. In the mediolateral direction, lateral incisor roots did not move distally (-0.65 to -0.96 mm DPARMs, p < .05), while those of canines did not move buccally, compared with the prediction (-0.75 mm DPARMs, p < .05).
In the four first-premolar extraction treatments with Invisalign, root movements were not achieved as predicted, particularly for anterior teeth in the anteroposterior direction.
本研究旨在比较成年人在拔除四颗前磨牙后使用 Invisalign 治疗前后的实际根移动和预测根移动。
本回顾性研究纳入了来自单个临床科室的 33 名连续成年人（22 名 Class I，9 名 Cusp-to-cusp Class II 和 2 名 Cusp-to-cusp Class III），他们在拔除前磨牙后完成了第一系列牙套治疗。将预处理的锥形束计算机断层扫描模型注册到预处理的表面扫描牙科模型（SSDM）上，以定位整个牙齿的预处理根尖。将这些根尖复制并转移到预测和治疗后的 SSDM 上，以获得预测和治疗后根尖的位置。使用配对 t 检验或 Wilcoxon 符号秩检验测试预测和实际根移动之间的差异（DPARMs）。
在前后方向上，上颌和下颌前牙的后根移动较差（3.24-5.74mm DPARMs，p<0.05）。在垂直方向上，上颌前牙的根获得了更大的内倾（0.70-0.93mm DPARMs，p<0.05），而下颌切牙的根获得的内倾则少于预测（0.57-0.65mm DPARMs，p<0.05）。在左右方向上，侧切牙的根没有向远中移动（-0.65 至-0.96mm DPARMs，p<0.05），而尖牙的根没有向颊侧移动，与预测值相比（-0.75mm DPARMs，p<0.05）。
在使用 Invisalign 进行的四颗前磨牙拔除治疗中，根移动没有达到预测的效果，特别是在前牙的前后方向上。
