下颌阻生智慧牙拔除下颌阻生智齿分类一下颌阻生智齿分类Classification of impaction of mandibular third molarsl第一种分类方法：l1 近中倾斜近中倾斜 Mesioangular l2 远中倾斜远中倾斜 distoangularl3 垂直垂直 verticall4 水平水平 horizontal l5 颊向颊向 buccoangular l6 舌向舌向 linguoangular l7 倒置倒置 inverted下颌阻生智齿分类二下颌阻生智齿分类二l第二种分类方法：la1 高位高位 The occlusal surface of the impacted tooth is at the same level as, or a little below that of,the second molarla2 中位中位The occlusal surface of the impacted tooth is at the middle of the crown of the secondmolar or at the same level as the cervical linela3 低位低位The occlusal surface of the impacted tooth is below the cervical line of the second molar下颌阻生智齿分类二l第二种分类方法：lb1 间隙大于牙冠间隙大于牙冠 The distance between the second molar and the anterior border of the ramus is greater than themesiodistal diameter of the crown of the impacted tooth, so that its extraction does not require bone removal from the region ofthe ramuslb2间隙小于牙冠间隙小于牙冠 The distance is less and the existing space is less than the mesiodistal diameter of the crown of the impacted toothlb3 没有间隙没有间隙There is no room between the second molar and the anterior border of the ramus, so that the entire impacted tooth or part of it is embedded in the ramus我临床上的分类l二大类：水平阻生和垂直阻生l所有的牙齿都可归为此二类l再综合前面所讲到的二种分类方法和牙根的情况进行详细分类描叙，这样的分类更加有利于临床实践，有利于拔牙手术的难度评估水平阻生水平阻生 113068水平高位、根粗大 109058中位 骨覆盖 114077水平低位粗根水平远中骨阻生空间小根多个 水平邻牙远中骨吸收根细113504水平 根粗大 邻牙远中骨吸收严重 龋损 水平根分叉大空间小水平阻生根分叉大水平根分叉大邻牙远中骨吸收水平 极低位 37根尖区113074垂直阻生高位远中骨阻生牙龈覆盖垂直牙巨大远中骨阻生垂直远中骨阻生空间小垂直低位弯根远中骨阻生牙根吸收远中骨阻生空间小较难垂直远中骨阻生空间小较难远中骨阻生偏颊侧远中牙挺难下去无间隙垂直低位远中骨阻力近下颌神经管难度大的牙增加拔牙难度的因素l巨大牙巨大牙l牙根长、粗大、多根、弯曲、分叉大牙根长、粗大、多根、弯曲、分叉大l骨埋伏低位于邻牙，去骨难度大骨埋伏低位于邻牙，去骨难度大垂直垂直低位骨埋伏邻牙的根分叉低位骨埋伏邻牙的根分叉l颊舌向象水平低位，挺不好使力颊舌向象水平低位，挺不好使力l颊部胖，暴露不充分颊部胖，暴露不充分l牙根骨粘连牙根骨粘连颊舌向水平低位挺不好使力水平低位阻生-颊舌向垂直阻生于颊侧根尖区 少见的拔牙并发症l下颌骨骨折l舌神经暴露l牙齿进入口底、咽旁间隙l牙挺折断l注射针头折断l牙根进入上颌窦、下颌管下颌骨骨折舌神经暴露牙齿进入口底、咽旁间隙Thank You启航号启航号