Abstract:

Objective To investigate the effect of the clinical application of molar uprighting in the treatment of impacted mandibular second molars. Methods A total of 16 cases of impacted mandibular second molars were chosen, and the impacted molars were treated with straight wire appliances and molar uprighting. Before and after treatment, the vertical angle of the molar, the height of the distal buccal tip, the height of the distal buccal tip of the anchorage molar, the depth of the periodontal pocket and the height of the alveolar bone were measured. Moreover, the treatment cycles of the third molar extraction group, the premolar group and the nonextraction group were compared. Results All impacted molars responded well to treatment. The vertical time of impacted molars was (1.34 ± 0.45) months, (2.20 ± 0.57) months, and (2.30 ± 0.45) months in the third molar extraction group, the premolar extraction group and the nonextraction group, respectively. The treatment time of the third molar extraction group was shorter than that of the other two groups, and the difference was statistically significant (P < 0.05). After treatment, the inclination of impacted second molars increased by (25.94 ± 8.85)°, the elongated distal buccal tip was depressed by (1.00 ± 1.48) mm, the depth of the proximal and middle periodontal pocket of impacted molars decreased by (1.21 ± 1.03) mm, and the height of the alveolar bone of the proximal and middle adjacent surfaces of impacted second molars increased by (4.57 ± 1.45) mm; these differences were statistically significant (P < 0.05). There was no significant difference in the height of the distal buccal tip of the first molar before and after treatment (P > 0.05). Conclusion Molar uprighting is an efficient, reliable, and convenient method that can shorten the treatment period. Extraction of crowded third molars is beneficial for the vertical and periodontal health of impacted second molars.

Key words: orthodontics, impacted teeth, molar uprighting, mandibular second molars, mesially inclined, inclination, height of distal buccal cusp, probing depth of mesial periodontal pocket, height of mesial alveolar bone

摘要：

目的 探讨使用磨牙竖直矫治器辅助矫治下颌阻生第二磨牙的临床应用的效果。方法 选取16例下颌第二磨牙阻生患者,采用直丝弓矫治器联合磨牙竖直簧矫治阻生磨牙,分别测量治疗前后磨牙角度及其远颊尖高度、支抗磨牙远颊尖高度、牙周袋深度、牙槽骨相对高度,同时比较分析拔除第三磨牙组、拔除前磨牙组与非拔牙矫治组对磨牙竖直治疗周期差异。结果 所有纳入矫治的阻生磨牙均得到良好的矫治。拔除第三磨牙组、拔除前磨牙组与非拔牙矫治组阻生磨牙竖直时间分别为（1.34 ± 0.45）个月、（2.20 ± 0.57）个月、（2.30 ± 0.45）个月，拔除第三磨牙组治疗时间比其他两组缩短，差异有统计学意义（P < 0.05）。治疗后阻生第二磨牙倾斜度平均增加（25.94 ± 8.85） °；伸长的远颊尖平均被压低（1.00 ± 1.48） mm；阻生第二磨牙近中牙周袋深度减少（1.21 ± 1.03） mm；阻生第二磨牙近中邻面牙槽骨高度相对增加（4.57 ± 1.45） mm，差异有统计学意义（P < 0.05）。治疗前后支抗第一磨牙远颊尖高度变化不显著，差异无统计学意义（P > 0.05）。结论 磨牙竖直矫治器辅助矫治阻生下颌第二磨牙高效、可靠、方便，能够缩短治疗周期。拔除拥挤的第三磨牙利于阻生第二磨牙的竖直及牙周健康。

关键词: 正畸, 阻生牙, 磨牙竖直簧, 下颌第二磨牙, 近中倾斜, 倾斜度, 远颊尖高度, 近中牙周袋探测深度, 近中牙槽骨高度