目的 探讨Nolla分期对青少年拔牙正畸患者下颌第三磨牙倾斜角的影响。方法 选择2018年10月—2022年10月收治的100例拔牙正畸青少年患者。100例患者均拔除了4颗前磨牙,共有100颗下颌第三磨牙,通过Nolla分期,可将100例患者分成四组,每组25例。Ⅰ组：牙冠正在形成,Ⅱ组：牙冠基本形成,Ⅲ组：牙根形成在1/2以下,Ⅳ组：牙根形成在1/2以上。在治疗前后,测量下颌第三磨牙倾斜角,对角度α的变化进行分析。结果 第三磨牙牙胚倾斜角、MP-SN、MP-FH在不同组间比较差异无统计学意义（F=0.256,P=0.857;F=0.033,P=0.992;F=0.028,P=0.994）;治疗前组间下颌第三磨牙角度比较差异无统计学意义（P>0.05）,治疗后不同组间下颌第三磨牙角比较差异有统计学意义（F=13.376,P<0.001）,治疗前后Ⅰ组、Ⅱ组、Ⅳ组第三磨牙的角度无差异（t=0.757,P=0.453;t=0.224,P=0.824;t=0.852,P=0.399）,Ⅲ组治疗后角度变化减少（t=3.697,P<0.001）。结论 青少年正畸拔牙后,下颌第三磨牙处于牙根形成阶段的一半以下可能会导致第三磨牙近中倾斜加重。当下颌第三磨牙处于牙冠形成阶段,牙冠形成超过一半时,第三磨牙角度变化较小。在治疗前应根据Nolla分期评估下颌第三磨牙的预后情况,并及时制定相应的干预策略。

Objective To explore the effect of Nolla staging on the inclination angle of mandibular third molars in adolescent orthodontic patients undergoing tooth extraction. Methods A total of 100 adolescent patients who underwent tooth extraction orthodontic treatment from October 2018 to October 2022 were included．All 100 patients had 4 premolars extracted,with a total of 100 mandibular third molars．According to Nolla staging,the 100 patients can be divided into 4 groups,with 25 cases in each group．Group I：The crown was forming,Group II：The crown was basically formed,Group III：The root formation was below 1/2,Group IV：The root formation was above 1/2．The inclination angle of the mandibular third molar was measured before and after treatment,and the angle α changes will be analyzed. Results There was no difference in the inclination angle,MP-SN,and MP-FH of the third molar tooth germ among different groups（F=0.256,P=0.857;F=0.033,P=0.992;F=0.028,P=0.994）．There was no difference in the angle of mandibular third molar teeth between groups before treatment（P>0.05）,the contrast of mandibular third molar angles between different groups after treatment was signifiant（F=13.376,P<0.001）,while the angles in Group I,Group and Group Ⅳ were not slgnificantly different（t=0.757,P=0.453;t=0.224,P=0.824;t=0.852,P=0.399）,and the angle change decreased after treatment in Group Ⅲ（t=3.697,P<0.001）. Conclusions After orthodontic extraction in adolescents,if the mandibular third molar is less than half of the root formation stage,it may lead to increased mesial inclination of the third molar．However,when the mandibular third molar is in the stage of crown formation and the crown is more than half formed,the angle change of the third molar is relatively small．Therefore,in clinical practice,Nolla staging should be evaluated in the prognosis of mandibular third molars before treatment and develop corresponding intervention strategies in a timely manner．

目的 探讨高速改良涡轮手机拔除下颌阻生第三磨牙的临床疗效。方法 回顾性分析2013年12月—2016年12月于本科室拔除下颌阻生第三磨牙600例临床案例,按拔除方式不同,将其分为高速涡轮手机组和传统凿骨劈冠组,各300例。其中高速涡轮手机组给予高速涡轮手机拔除法拔除下颌第三磨牙,传统凿骨劈冠组给予传统凿骨劈冠拔除法拔除下颌第三磨牙。统计分析两组患者拔出后疗效情况、拔除使用时间、以及拔除后疼痛度及张口受限度情况。结果 高速涡轮手机组患者拔牙优良率明显高于传统凿骨劈冠组,差异有统计学意义(P<0.05),而疗效差发生率明显低于传统凿骨劈冠组,差异有统计学意义(P<0.05);高速涡轮手机组患者拔牙时间在30min内人数明显多于传统凿骨劈冠组,差异有统计学意义(P<0.05),而在30min以上的人数明显少于传统凿骨劈冠组,差异有统计学意义(P<0.05);高速涡轮手机组患者拔牙后疼痛度1级和张口受限度1级人数明显多于传统凿骨劈冠组,差异有统计学意义(P<0.05),而术后疼痛度2级、3级和张口受限度2级、3级均明显少于传统凿骨劈冠组,差异有统计学意义(P<0.05)。结论 高速改良涡轮手机拔除下颌阻生第三磨牙具有创口小,伤口愈合较良好,用时短以及能促进患者术后舒适。