关键词: 拔牙, 牙槽窝复位, 锥形束CT, 牙槽骨宽度, 正畸

Abstract: Objective    To investigate the effect of alveolar sockets non-repositioning on alveolar bone width preservation in adolescent patients，where teeth are extracted after loosening the periodontal attachment of the to-be-extracted teeth using orthodontic force. Methods    A total of 32 adolescent patients undergoing orthodontic treatment with tooth extraction were selected from the Department of Stomatology，Fushun County People's Hospital，between 2022 and 2024. After 3 months of orthodontic alignment of the dentition，the bilateral maxillary first premolars were extracted from each patient. A self-control method was adopted：one side of the alveolar socket was randomly selected for non-repositioning（non-repositioning group），while the other side was subjected to gentle-force repositioning（repositioning group）. Cone beam CT（CBCT） scanning was performed at three time points：before orthodontic treatment（T1），on the day of tooth extraction（T2），and 3 months after tooth extraction（T3）. Subsequent orthodontic treatment was conducted to close the extraction spaces. The alveolar bone width measured at T1，T2，and T3 was recorded as W1，W2，and W3，respectively，and the changes in alveolar bone width between different time points were calculated（W2-W1，W3-W1，and W3-W1）. Results  Comparison of alveolar bone width at the same time points between the two groups showed：In the non-repositioning group，W2 and W3 were（10.93 ± 0.83）mm and（8.91 ± 0.73）mm，respectively，which were larger than those in the repositioning group ［（9.83 ± 0.64）mm and（7.76 ± 0.67）mm］，and the differences were statistically significant（t = 5.940 and 6.552，both P < 0.001）；there was no statistically significant difference in W1 between the non-repositioning group ［（10.29 ± 0.77）mm] and the repositioning group ［（10.11 ± 0.69）mm］（P > 0.05）. Comparison of the changes in alveolar bone width between time points in the two groups showed：Statistically significant differences were observed between the two groups in terms of W2-W1 and W3-W1（t = 10.539 and -8.748，both P < 0.001），while no statistically significant difference was found in W3-W2 between the two groups（P > 0.05）. There was no correlation between W2-W1 and W3-W1 in the non-repositioning group（r = 0.033，P = 0.858），whereas a positive correlation was observed between W2-W1 and W3-W1 in the repositioning group（r = 0.498，P = 0.004）. Conclusion    After extracting teeth in adolescent patients following the release of periodontal attachments using orthodontic force，not repositioning the alveolar socket is more conducive to maintaining the width of the alveolar bone than repositioning it. The degree of alveolar socket repositioning may affect changes in the width of the alveolar socket，but the changes in alveolar bone width within 3 months after tooth extraction are not related to whether the alveolar socket is repositioned.

Key words: tooth extraction, alveolar socket repositioning, cone beam CT, alveolar bone width, orthodontics