下颌阻生第三磨牙与下颌管重叠时的三维位置关系与拔除方法研究  

Three-dimensional position of the overlap relations of impacted mandibular third molar and mandibular canal

作　　者：容明灯[1] 卢鹏 许竞[1] 曾曙光[1] 曹彦南[1] 杨静[1] 邝喆[1] 李晓敏[1] 

机构地区：[1]广东省口腔医院·南方医科大学附属口腔医院,广东广州510280 [2]山东省临沂市妇幼保健院口腔科

出　　处：《广东牙病防治》2012年第9期484-487,共4页Journal of Dental Prevention and Treatment

摘　　要：目的探讨曲面体层X线片示下颌阻生第三磨牙根尖部与下颌管重叠时的三维位置关系分类,以指导临床采用恰当方法拔出下颌阻生第三磨牙。方法选取在曲面体层X线片上牙根与下颌管有重叠的57颗下颌阻生第三磨牙,行锥形束CT(cone beam computed tomography,CBCT)检查,了解两者间的三维位置关系,拟定安全的拔除手术方案。结果 55例患者的57颗患牙的CBCT影像中,22颗患牙牙根(38.6%)突破下颌管壁位于下颌管内;30颗患牙(52.6%)的牙根位于下颌管的舌侧,未与下颌管发生接触;4颗患牙(7.0%)的牙根位于下颌管的颊侧,未与下颌管发生接触;1颗患牙(1.8%)的双根跨于下颌管间。57颗患牙均顺利完成拔牙手术,1例患者(1.8%)出现短暂的下唇麻木于术后1个月后恢复。结论曲面体层X线片上下颌阻生第三磨牙根尖部与下颌管重叠的病例中,下颌第三磨牙的根尖多位于下颌管的舌侧或位于下齿槽神经管内,CBCT检查对拟定正确安全的拔除术式和降低下齿槽神经损伤发生率具有重要的意义。Objective To study the method in accurately deciding the threedimensional positional relationship when impacted mandiladar third molar was cwerlapped with mandibular canal ma the panoramic Xray fihn, so as to use appro priate clinical melhods to exlraet the mandibular third molar. Methods Fiftyseven impacted mandibular third molars were eheckedby CBCT, which were overlapped with nmndibular canal on the panoramic Xray film, and then a detailed classification and appropriate surgical plan were made. Results The position relationship types on CBCT were as fol lows： 22 impacted mamtibular third molars＇routs were inside lhe mandibular canal; 30 impacted mandibular third molarswere loeated in lingual side of the mandibular canal; 4 impaeted mandibular third molars were located in buccal side of the mandibular canal; 1 impacted mandibular third molar was in both sides of the mandibular canal, with the canal lied between the two roots of the impacted molars. All the 57 impacted mandibular third molars were suceessfully extracted, and short period numtmess happened in only one easehis one side of lower lip. Conclusion In these eases in which im pacted mandibular third molar were overlapped with mandibular canal on the panoramic Xray film, muhitude of IMTMs were located in the lingual side of mandibular side or were inside the mandibular eanal on CBCT, it is necessary fi）r a fur ther CBCT checking, so as to reduce the incidence of inferior alveolar nerve injury.

关 键 词：下颌阻生第三磨牙 体层摄影术 锥形束CT 牙拔除术 牙 阻生 磨牙 第三 放射摄影术 牙科 拔牙 

分 类 号：R782.05[医药卫生—口腔医学]