Accuracy of Cone-beam Computed Tomography in the Detection of a Second Mesiobuccal Root Canal in Endodontically Treated Teeth: An Ex Vivo Study.
BACKGROUND
There is a high incidence of a second mesiobuccal root canal (MB2) in maxillary molars. The study aim is to assess the accuracy of cone-beam computed tomographic (CBCT) imaging in detecting a second mesiobuccal root canal in endodontically treated maxillary molars.


METHODS
The study sample consisted of 60 extracted maxillary molars, which were endodontically opened and examined under a dental operating microscope for the presence of an MB2. The teeth were then further examined using micro-computed tomographic imaging as the gold standard. Root canals were filled (except the MB2) and were then subdivided into an experimental and a control group. After fixing the teeth in a dry human skull, they were scanned using CBCT imaging (AccuiTomo 170; Morita Inc, Tarumi-cho Suita City, Osaka, Japan). The observers for this study were 2 experienced radiologists blinded to the group allocation of controls and experiments; they evaluated the images twice independently. Sensitivity, specificity, and accuracy were calculated as well as the kappa values for both inter- and intraobserver agreement.


RESULTS
From 30 teeth, which were diagnosed without an MB2 under examination with a dental operating microscope, 6 teeth proved to have an MB2 using μCT (20%). Intraobserver reliability was high for both observers 1 (R = 0.85) and 2 (R = 0.96). Interobserver reliability as assessed by the Cohen kappa was excellent (R = 0.89). CBCT sensitivity for detecting an MB2 was 96%, specificity was 100%, and total accuracy was 98%.


CONCLUSIONS
CBCT imaging is a suitable diagnostic technique for detecting a missed MB2 in endodontically treated teeth.
Dental Materials Research Center, Department of Restorative Dentistry, School of Dentistry, University of Medical Sciences, Isfahan, Iran; Department of Cariology Endodontology Pedodontology, Academic Centre for Dentistry Amsterdam, Universiteit van Amsterdam and Vrije Universiteit, The Netherlands. Electronic address: hmirmoha@acta.nl.
Hesam
H
Mirmohammadi
Private Practice, Rotterdam, The Netherlands.
Lamees
L
Mahdi
Private Practice, Niuew-Vennep, The Netherlands.
Poerya
P
Partovi
Department of Endodontics, Torabinejad Dental Research Center, School of Dentistry, University of Medical Sciences, Isfahan, Iran.
Abbasali
A
Khademi
Department of Cariology Endodontology Pedodontology, Academic Centre for Dentistry Amsterdam, Universiteit van Amsterdam and Vrije Universiteit, The Netherlands.
Hagay
H
Shemesh
Department of Oral Implants and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam, Universiteit van Amsterdam and Vrije Universiteit, The Netherlands.
Bassam
B
Hassan
D054893:Cone-Beam Computed Tomography; D003786:Dental Pulp Cavity / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D006801:Humans; D008437:Maxilla / Q000000981:diagnostic imaging; D008963:Molar / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D018915:Root Canal Preparation; D019553:Tooth, Nonvital / Q000000981:diagnostic imaging*
Cone-beam computed tomography; endodontics; maxillary molars; microscope; second mesiobuccal