Somma F, Leoni D, Plotino G, Grande N M, Plasschaert A
Department of Endodontics, Catholic University of Sacred Heart, Rome, Italy.
Int Endod J. 2009 Feb;42(2):165-74. doi: 10.1111/j.1365-2591.2008.01472.x.
To investigate ex vivo, the root canal morphology of the MB root of maxillary first molar teeth by means of micro-computed tomography.
Thirty extracted intact human maxillary first molar teeth were selected for micro-tomographic analysis (SkyScan 1072, Aartselaar, Belgium) with a slice thickness of 38.0 mum. The following data regarding the MB root were analysed and recorded: number and type of root canals, prevalence of isthmuses, prevalence of intercanal connections, presence of accessory canals, presence of loops and number of apical foramina.
The MB2 canal was present in 80% of specimens and was independent in 42% of these cases. When present, the MB2 canal merged with the MB1 canal in 58% of cases. Communications between the two canals were found in all specimens, with isthmuses in 71% of the cases. These communications and isthmuses were respectively in 42% and 54% of the cases in the coronal third, in 59% and 79% of the cases in the middle third and in 24% and 50% of the cases in the apical third. A single apical foramen was found in 37% of specimens, two apical foramina were present in 23% of the cases, with three or more separate apical foramina occurring in 40% of the specimens.
The MB root canal anatomy was complex: a high incidence of MB2 root canals, isthmuses, accessory canals, apical delta and loops was found.
通过显微计算机断层扫描技术对离体上颌第一磨牙近中颊根的根管形态进行研究。
选取30颗完整拔除的人上颌第一磨牙进行显微断层扫描分析（SkyScan 1072，比利时阿尔斯特），切片厚度为38.0微米。分析并记录以下关于近中颊根的数据：根管数量和类型、峡部发生率、根管间连接发生率、副根管的存在情况、袢的存在情况以及根尖孔数量。
80%的标本存在MB2根管，其中42%的MB2根管独立存在。当MB2根管存在时，58%的情况下与MB1根管融合。所有标本中均发现两根管之间存在交通，71%的病例存在峡部。这些交通和峡部分别在冠方三分之一的病例中占42%和54%，在根中三分之一的病例中占59%和79%，在根尖三分之一的病例中占24%和50%。37%的标本发现有单个根尖孔，23%的病例有两个根尖孔，40%的标本有三个或更多个独立的根尖孔。
近中颊根管解剖结构复杂：发现MB2根管、峡部、副根管、根尖分歧和袢的发生率较高。
