辽宁地区汉族人下颌第二恒磨牙牙根和根管数目的锥形束CT研究

目的：利用锥形束CT（CBCT）扫描评估辽宁地区汉族人下颌第二恒磨牙牙根和根管数目的情况。方法：调取于我院口腔科行CBCT扫描患者的图像资料，统计分析下颌第二恒磨牙牙根和根管数目的情况。结果：在900例下颌第二恒磨牙中，双根的发生率为51．22％，其中82％的近中根内为双根管，100％的远中根内为单根管；三根的发生率为2．18％；融合根的发生率为46．6％，其中完全融合的锥形根占5．71％，不完全融合的C形根（C型根管）占40．89％，C型根管发生率在男女性别间差异无统计学意义（p〉0．05），以双侧对称性分布较多，单侧发生率以右侧为多。结论：在辽宁地区汉族人中，下颌第二恒磨牙以双根或融合根居多，c形根（C型根管）的发生率较高。

Use of cone-beam computed tomography to evaluate the number of roots and canals of mandibular second perma- nent molars in Han people of Liaoulng province

Objective： To evaluate the number of roots and canals of mandibular second permanent molars in Han peo- ple of Liaoning Province using cone-beam computed tomography（CBCT）. Methods： CBCT images of dentitions were col- lected retrospectively and analyzed for the number of roots and canals of mandibular second permanent molars. Results： The majority of mandibular second permanent molars （51.22%） had two separate roots, with two canals in mesial roots （82%） and one canal in distal roots （100%）. Three roots were identified in 2.18% of the teeth examined. Fused roots oc- curred in 46.6% mandibular second permanent molars, while 5.71% were conical roots and 40.89% were C-shaped roots. In addition, the incidence of C-shaped roots and canals according to sex showed no statistical significance （P〉0.05）, and most occurred bilaterally. Conclusion： In Han people of Liaoning Province, mandibular second permanent molars commonly have fused roots or two roots and a high prevalence for C-shaped roots.