Baratto Filho Flares, Zaitter Suellen, Haragushiku Gisele Aihara, de Campos Edson Alves, Abuabara Allan, Correr Gisele Maria
Department of Dentistry, Positivo University (UP), Curitiba, PR, Brazil.
J Endod. 2009 Mar;35(3):337-42. doi: 10.1016/j.joen.2008.11.022.
The success of endodontic treatment depends on the identification of all root canals so that they can be cleaned, shaped, and obturated. This study investigated internal morphology of maxillary first molars by 3 different methods: ex vivo, clinical, and cone beam computed tomography (CBCT) analysis. In all these different methods, the number of additional root canals and their locations, the number of foramina, and the frequency of canals that could or could not be negotiated were recorded. In the ex vivo study, 140 extracted maxillary first molars were evaluated. After canals were accessed and detected by using an operating microscope, the teeth with significant anatomic variances were cleared. In the clinical analysis, the records of 291 patients who had undergone endodontic treatment in a dental school during a 2-year period were used. In the CBCT analysis, 54 maxillary first molars were evaluated. The ex vivo assessment results showed a fourth canal frequency in 67.14% of the teeth, besides a tooth with 7 root canals (0.72%). Additional root canals were located in the mesiobuccal root in 92.85% of the teeth (17.35% could not be negotiated), and when they were present, 65.30% exhibited 1 foramen. Clinical assessment showed that 53.26%, 0.35%, and 0.35% of the teeth exhibited 4, 5, and 6 root canals, respectively. Additional root canals were located in this assessment in mesiobuccal root in 95.63% (27.50% could not be negotiated), and when they were present, 59.38% exhibited 1 foramen. CBCT results showed 2, 4, and 5 root canals in 1.85%, 37.05%, and 1.85% of the teeth, respectively. When present, additional canals showed 1 foramen in 90.90% of the teeth studied. This study demonstrated that operating microscope and CBCT have been important for locating and identifying root canals, and CBCT can be used as a good method for initial identification of maxillary first molar internal morphology.
牙髓治疗的成功取决于能否识别出所有根管，以便对其进行清理、塑形和充填。本研究采用三种不同方法对上颌第一磨牙的内部形态进行了研究：离体研究、临床研究和锥形束计算机断层扫描（CBCT）分析。在所有这些不同方法中，记录了额外根管的数量及其位置、根尖孔的数量以及能够或无法疏通的根管频率。在离体研究中，对140颗拔除的上颌第一磨牙进行了评估。使用手术显微镜进入并检测根管后，对具有明显解剖变异的牙齿进行清理。在临床分析中，使用了一所牙科学院在两年期间接受牙髓治疗的291例患者的记录。在CBCT分析中，对54颗上颌第一磨牙进行了评估。离体评估结果显示，67.14%的牙齿有第四根管，此外还有一颗有7个根管的牙齿（0.72%）。92.85%的牙齿额外根管位于近中颊根（17.35%无法疏通），当存在额外根管时，65.30%有1个根尖孔。临床评估显示，分别有53.26%、0.35%和0.35%的牙齿有4、5和6个根管。在该评估中，额外根管位于近中颊根的比例为95.63%（27.50%无法疏通），当存在额外根管时，59.38%有1个根尖孔。CBCT结果显示，分别有1.85%、37.05%和1.85%的牙齿有2、4和5个根管。当存在额外根管时，在所研究的牙齿中，90.90%有1个根尖孔。本研究表明，手术显微镜和CBCT对根管的定位和识别很重要，CBCT可作为初步识别上颌第一磨牙内部形态的良好方法。
