微种植体作为间接支抗近中移动下颌第二磨牙的疗效观察

Effectiveness of micro implant as indirect anchorage in mesial movement of mandibular second molar

目的观察微种植体作为间接支抗近中移动下颌第二磨牙的疗效。方法选择12例单侧或双侧下颌第一磨牙因龋坏拔除的正畸患者。牙弓排齐整平后,用0.48 mm×0.64 mm（0.019英寸×0.025英寸）不锈钢方丝作主弓丝,在下颌双尖牙区颊侧齿槽骨植入微种植体作为间接支抗,前牙连续结扎,通过缺牙区近远中牙齿颊舌侧的牵引钩和舌扣牵引下颌第二磨牙,关闭间隙。结果 12例患者15颗患牙经过13~19个月的牵引,下颌第二磨牙均达到预期的位置,X线片显示下颌第二磨牙根直立,没有发生吸收。头影测量结果显示下颌第二磨牙近中移动量平均9.8 mm,其中最大为12.1 mm,最小8.3 mm。L7-MP治疗前的平均值为97.2°,治疗后的平均值为103.3°,L5-L7的夹角明显变小,其平均值由治疗前的15.6°减少为7.1°。结论应用微种植体作为间接支抗近中移动下颌第二磨牙的效果较显著。

Objective To evaluate the effectiveness of the mesial movement of the mandibular second molar,supported by micro implant served as indirect anchorage. Methods Twelve patients were treated,whose unilateral or bilateral mandibular first molar was extracted due to extensive caries was extracted. After leveling the dental arch,0. 019 inch × 0. 025 inch square arch wire was used when micro implant was inserted in mandibular premolar region. Front teeth were ligated. Then mesial movement of the mandibular second molar was made moved mesially by indirect anchorage. Results All patients achieved the expecting effect after 13- 19 months treatment,the The mandibular second molar was in preconceived position. X-ray showed that the straight root of the mandibular second molar was straightened without nonassimilationresorption. Conclusion Micro implant as indirect anchorage can effectively make the mesial movement of mandibular second molar when used as indirect anchorage.