title: Detection of a secondary mesio-buccal canal in maxillary first molar: A comparative study.
abstract: OBJECTIVE
  The purpose of this study was to clarify detection characteristics of the secondary mesio-buccal canal in maxillary first molars using various methods.
  
  
  METHODS
  The root canal system of 86 extracted human maxillary first molars was inspected using micro-focus-computed tomography to accurately determine the number of canals. Radiographs or floors of the pulp chamber for all samples were observed for the secondary mesio-buccal canal with computed tomography for dentistry, digital dental radiography, magnifier, or the naked eye. Sensitivity, specificity, positive, and negative predictive values and diagnostic accuracy for these four methods were investigated using the results from the micro-focus-computed tomography inspection as the gold standard. All samples of each method were observed by 10 endodontists. Using these results, the χ(2) test was used to compare and analyze differences between the various conditions (P<0.05).
  
  
  RESULTS
  The secondary mesio-buccal canal could be recognized in 60.9% of samples with the micro-focus-computed tomography. No significant difference was seen between efficiencies of the computed tomography for dentistry and the micro-focus-computed tomography. The computed tomography for dentistry was superior to the other three methods.
  
  
  CONCLUSIONS
  Detectability of the secondary mesio-buccal canal in the maxillary first molar was superior using dental-computed tomography compared to digital dental radiography, magnification telescope, and the naked eye.
authors.affiliation: Department of Endodontics, Tsurumi University School of Dental Medicine, 2 1 3 Tsurumi, Tsurumi ku, Yokohama 230 8501, Japan.
authors.forename: Noriyasu
authors.initials: N
authors.lastname: Hosoya
authors.forename: Takumasa
authors.initials: T
authors.lastname: Yoshida
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Iino
authors.forename: Takashi
authors.initials: T
authors.lastname: Arai
authors.forename: Akira
authors.initials: A
authors.lastname: Mishima
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kobayashi