Wolf Thomas Gerhard, Paqué Frank, Zeller Maximilian, Willershausen Brita, Briseño-Marroquín Benjamín
Department of Operative Dentistry, Johannes Gutenberg University Medical Center, Mainz, Germany.
Division of Preventive Dentistry, Periodontology, and Cariology, University of Zürich Center of Dental Medicine, Zürich, Switzerland.
J Endod. 2016 Apr;42(4):610-4. doi: 10.1016/j.joen.2016.01.004. Epub 2016 Feb 20.
The aim of this study was to investigate the root canal system morphology of the mandibular first molar by means of micro-computed tomography.
The root canal configuration, foramina, and accessory canals frequency of 118 mandibular first molars were investigated by means of micro-computed tomography and 3-dimensional software imaging. A 4-digit system describes the root canal configuration from the coronal to apical thirds and the main foramina number.
The most frequent root canal configurations in mesial root were 2-2-2/2 (31.4%), 2-2-1/1 (15.3%), and 2-2-2/3 (11.9%); another 24 different root canal configurations were observed in this root. A 1-1-1/1 (58.5%), 1-1-1/2 (10.2%), and 16 other root canal configurations were observed in the distal root. The mesiobuccal root canal showed 1-4 foramina in 24.6%, and the mesiolingual showed 1-3 foramina in 28.0%. One connecting canal between the mesial root canals was observed in 30.5% and 2 in 3.4%. The distolingual root canal showed 1-4 foramina in 23.7%, whereas a foramen in the distobuccal root canal was rarely detected (3.4%). The mesiobuccal, mesiolingual, and distolingual root canals showed at least 1 accessory canal (14.3, 10.2, and 4.2%, respectively), but the distobuccal had none.
The root canal configuration of mandibular first molars varies strongly. According to our expectations, both the mesial and distal roots showed a high number of morphologic diversifications. The root canal system of the mesial root showed more root canal configuration variations, connecting and accessory canals than the distal root.
本研究旨在通过显微计算机断层扫描研究下颌第一磨牙的根管系统形态。
通过显微计算机断层扫描和三维软件成像，研究118颗下颌第一磨牙的根管形态、根尖孔及副根管频率。采用四位数系统描述从冠部到根尖三分之一的根管形态及主要根尖孔数量。
近中根最常见的根管形态为2-2-2/2（31.4%）、2-2-1/1（15.3%）和2-2-2/3（11.9%）；该根还观察到另外24种不同的根管形态。远中根观察到1-1-1/1（58.5%）、1-1-1/2（10.2%）以及另外16种根管形态。近中颊根管24.6%显示1-4个根尖孔，近中舌根管28.0%显示1-3个根尖孔。30.5%的近中根管之间观察到1条连接管，3.4%观察到2条。远中舌根管23.7%显示1-4个根尖孔，而远中颊根管很少检测到根尖孔（3.4%）。近中颊、近中舌和远中舌根管至少有1条副根管（分别为14.3%、10.2%和4.2%），但远中颊根没有。
下颌第一磨牙的根管形态差异很大。正如我们所预期的，近中根和远中根均表现出大量形态学变异。近中根的根管系统比远中根表现出更多的根管形态变异、连接管和副根管。
