Navarro Leopoldo Forner, Luzi Arlinda, García Amelia Almenar, García Adela Hervás
Dental Pathology and Therapeutics Unit, University of Valencia, Valencia, Spain.
Med Oral Patol Oral Cir Bucal. 2007 Dec 1;12(8):E605-9.
Systematic anatomical studies corroborate the anatomical complexity of the root canal system. Deviations from the norm such as multiple orifices, apical deltas, accessory canals and other variations are frequent.
To present clinical reports of mandibular molars with three canals in the mesial root and two in vitro studies of the morphology of these canals, together with a review of the literature.
Three clinical reports are presented of mandibular molars where three canals in the mesial roots were treated endodontically. Two in vitro studies were performed, one using computerized tomography and the other with scanning electron microscopy, to describe the morphology of the mesial root canals of permanent first molars. The scientific literature on this anatomical situation was also reviewed.
The tomographic study found that the prevalence of a third mesial canal in the 27 teeth analysed was 14.81%; the microscopic study of 25 teeth found it to be 12%. The review of the literature encountered that the authors who report cases such as these found prevalences ranging from 1% to 15%.
From the teeth analysed in vitro, it is concluded that a third mesial canal may be present in a mandibular first molar in approximately 13% of cases. Clinically, the third canal is difficult to find and exhibits a very variable morphology, which may present anastomosis with the other canals.
系统的解剖学研究证实了根管系统的解剖复杂性。诸如多个根管口、根尖分歧、副根管等与正常情况的偏差很常见。
呈现下颌磨牙近中根有三根根管的临床报告以及对这些根管形态的两项体外研究，并对文献进行综述。
呈现了三例下颌磨牙近中根有三根根管并接受牙髓治疗的临床报告。进行了两项体外研究，一项使用计算机断层扫描，另一项使用扫描电子显微镜，以描述恒牙第一磨牙近中根管的形态。还对关于这种解剖情况的科学文献进行了综述。
断层扫描研究发现，在分析的27颗牙齿中，第三近中根管的发生率为14.81%；对25颗牙齿的显微镜研究发现其发生率为12%。文献综述发现，报告此类病例的作者所发现的发生率在1%至15%之间。
从体外分析的牙齿得出结论，下颌第一磨牙中约13%的病例可能存在第三近中根管。临床上，第三根管很难找到，并且形态变化很大，可能与其他根管存在吻合。
