4种超声骨刀去骨法在高难度下颌阻生第三磨牙拔除术中的应用

目的：探讨应用超声骨刀进行4种去骨拔牙法在高难度下颌阻生第三磨牙拔除术中的应用效果。方法：根据改良的纳入标准将55例患者的74颗牙定为高难度下颌阻生第三磨牙。以X线平片和锥形束CT（CBCT）为依据,按不同的阻生牙情况,设计4种超声骨刀去骨拔除方法：术式1为整体去骨拔除,术式2为分块去骨拔除,术式3为去骨分牙拔除,术式4为牙骨一并拔除。记录去骨方式、手术时间以及围术期并发症,评价应用效果。结果：所有阻生牙均顺利拔除,4种去骨拔除术中,术式1为38颗牙（51.4%）,术式2为18颗牙（24.3%）,术式3为12颗牙（16.2%）,术式4为6颗牙（8.1%）。平均用时为15 min（8-26 min）。所有病例随访1个月,仅2例（2.7%）出现术后局部感染,予以引流、抗感染治疗,1周内痊愈。结论：本研究创立的4种超声骨刀去骨拔牙方法能顺利拔除所有类型的高难度下颌阻生第三磨牙,且用时较短,并发症较少。

Use of 4 osteotomy methods by piezosurgery for removal of complicated mandibular third molar

PURPOSE： To introduce 4 osteotomy methods by piezosurgery to remove complicated mandibular third molar,and evaluate its effect. METHODS： Fifty-five patients with 74 complicated impacted mandibular third molar underwent extraction with piezoelectric device. Four osteotomy methods were proposed by piezosurgery according to different situation： method 1 was complete bone removal technique, method 2 was segmental bone removal technique, method 3 was bone removal combined with tooth splitting technique, method 4 was block bone removal technique. The osteotomy procedure, operating time, peri-operative complications were documented. RESULTS： All impacted mandibular third molars were successfully removed. The average time of operation was 15 min（range： 8-26 min）. The distribution was as follows： 38 molars（51.4%） by method 1, 18 molars（24.3%） by method 2, 12 molars（16.2%） by method 3, 6 molars（8.1%）by method 4. Two cases（2.7%） developed postoperative infection, and recovered by symptomatic treatment within a week.CONCLUSIONS： The 4 osteotomy methods by piezosurgery provide an effective way for complicated impacted mandibular third molar removal and may improve surgical efficiency and reduce morbidity.