Khademi Abbasali, Mehdizadeh Mojdeh, Sanei Maryam, Sadeqnejad Hamidreza, Khazaei Saber
Department of Endodontic and Dental Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
Department of Oral and Maxillofacial Radiology and Dental Implant Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran.
Dent Res J (Isfahan). 2017 Sep-Oct;14(5):321-325. doi: 10.4103/1735-3327.215964.
Different techniques are used to evaluate the anatomy of root canal system. The present study was aimed to evaluate the root canal morphology of mandibular premolars using clearing and cone beam computed tomography (CBCT) techniques.
A total of 182 mandibular first and second premolars were evaluated using 100 μm CBCT cross sections. The root canal morphology of the teeth was determined based on Vertucci classification in relation to the prevalence of C-shaped canals, lateral canals, and furcation location. Having removed the pulp tissue with NaOCl solution and staining the root canals with India ink, the samples were decalcified with 5% nitric acid and dehydrated with isopropyl alcohol. Finally, the samples were cleared with methyl salicylate. Data were analyzed by SPSS 16 software using McNamara, -test, and Kappa coefficient.
After Type I, the most frequent morphologies in both first and second premolars were Type V followed by Type IV. The prevalence rates of C-shaped morphology in first premolars using clearing and CBCT were 4.4% and 6.6%, respectively. However, no C-shaped morphology was found in second premolars. The maximum and minimum levels of agreement between the two techniques were observed in Type IV and Type V root canal morphologies, respectively. Extra root canals were identified in 25% and 13% of the first and second premolars, respectively.
CBCT showed a higher accuracy in determining C-shaped root canal morphology than the clearing technique. It also showed the least accuracy in diagnosing lateral root canals.
采用不同技术评估根管系统的解剖结构。本研究旨在使用透明标本技术和锥形束计算机断层扫描(CBCT)技术评估下颌前磨牙的根管形态。
使用100μm的CBCT横断面评估总共182颗下颌第一和第二前磨牙。根据Vertucci分类法确定牙齿的根管形态,涉及C形根管、侧支根管的发生率以及根分叉位置。用次氯酸钠溶液去除牙髓组织并用印度墨水对根管进行染色后,样本用5%硝酸脱钙并用异丙醇脱水。最后,样本用冬青油透明处理。使用SPSS 16软件通过McNamara检验和kappa系数分析数据。
在I型之后,第一和第二前磨牙中最常见的形态是V型,其次是IV型。使用透明标本技术和CBCT时,第一前磨牙中C形形态的发生率分别为4.4%和6.6%。然而,在第二前磨牙中未发现C形形态。两种技术之间的一致性最高和最低水平分别出现在IV型和V型根管形态中。第一和第二前磨牙中分别有25%和13%发现额外根管。
CBCT在确定C形根管形态方面比透明标本技术具有更高的准确性。在诊断侧支根管方面,其准确性也最低。