不同部位植入种植钉远中移动上颌牙列的临床效果研究

Treatment effects of maxillary dentition distalization using miniscrews at different sites

目的对比不同部位植入种植钉远中移动上颌牙列的治疗效果,为临床有效应用种植钉远中移动骨性Ⅱ类错的上颌牙列提供参考。方法选取2014年1月至2017年6月就诊于大连医科大学附属大连市口腔医院正畸科的骨性Ⅱ类错成年女性患者24例。年龄21～26岁,平均(23.8±1.2)岁。按种植钉的植入部位平均分为3组:A组,将种植钉植入上颌第二前磨牙和第一磨牙牙根之间;B组,将种植钉植入颧牙槽嵴区;C组,将种植钉植入第二磨牙颊侧骨皮质区。对所有患者治疗前和种植钉施力4个月后的头颅定位侧位片进行测量分析,观察各组上颌牙列远中移动的临床效果和特征。结果各组患者种植钉施力4个月后较治疗前,上颌磨牙远中移动明显(均P <0.05)。其中A组患者上颌第一磨牙远中倾斜最为明显,上颌第一磨牙远中倾斜角度(MTD)为2.28°±0.14°;B组患者上颌切牙及上颌磨牙明显压低,上颌中切牙切缘到X轴的距离(U1-X)减小(1.0±0.9)mm,上颌第一磨牙牙冠近中面最突点到X轴的距离(U6-X)减小(1.4±0.7)mm;C组患者上颌牙列远中移动最为明显,上颌中切牙切缘到Y轴的距离(U1-Y)减小(2.0±0.8)mm;上颌第一磨牙牙冠近中面最突点到Y轴的距离(U6′-Y)减小(2.6±1.2)mm;其差异均具有统计学意义(均P <0.05)。结论不同部位植入种植钉均可远中移动上颌牙列,在上颌第二前磨牙和第一磨牙牙根之间植入种植钉时,上颌第一磨牙产生明显远中倾斜移动;在颧牙槽嵴区植入种植钉时,对上颌切牙及磨牙产生压低作用;在上颌第二磨牙颊侧骨皮质区植入种植钉时,远移上颌牙列的效率最高。

Objective To evaluate the treatment effects of maxillary dentition distalization using orthodontic miniscrews placed in different insertion sites and to provide a clinical guidance in choosing the most efficient site of maxillary dentition disatalization. Methods Twenty-four female patients were selected from January 2014 to June 2017 at Department of Orthodontics,Dalian Stomatological Hospital,the age of all patients in our study ranging from 21 to 26 years old,who presented with dental and skeletal class Ⅱ malocclusion. We divided the samples into three groups:Group A:miniscrews were placed in the region between the second premolar and the first molar;Group B:miniscrews were inserted in the infrazygomaticcrest site; Group C:miniscrews were inserted and inclined in the the buccal region of the maxillary second molars. Measurements were performed on the lateral cephalometric radiogragh at two time points:the first was before the orthodontic treatment,and the second was at 4 months after distalization of maxillar dentition. Results Four months after distalization of the maxillary dentition we found that in group A the molar was obviously distally inclined,the inclination angle of the upper first molar toward distal(MTD)was 2.28° ± 1.4°. In group B,the upper incisors and first molar were intruded,the distance from the incisal edge of the maxillary central incisor to the X axis(U1-X)was decreased(1.0 ± 0.9)mm;the distance from the mesial proximal contact area of maxillary first molar'mesial surface to the X axis(U6-X)was decreased(1.4 ± 0.7)mm. In group C,the upper incisors were retracted obviously,the distance from the incisal edge of the maxillary central incisor to the Y axis(U1-Y)was decreased(2.0 ± 1.8)mm,and the distance from the mesial proximal contact area of maxillary first molar'mesial surface to the Y axis(U6′-Y)was decreased(2.6 ± 1.2)mm,the difference being statistical (all P < 0.05). Conclusion Orthodontic miniscrews placed in different insertion sites all can make maxillary dentition distalization. The molar was obviously distally inclined in group A. The upper incisors and first molar were intruded in group B. The efficiency of maxillary dentition distalization was the highest in group C.