title: [Comparative study of root canal morphology of mandibular first premolar by micro-CT and radio visio graphy].
abstract: OBJECTIVE
  To compare the consistency of root canal configuration types of mandibular first premolar by using micro-CT and radio visio graphy (RVG).
  
  
  METHODS
  One hundred extracted mandibular first premolars with complete dental root and apex which received no endodontic treatment were randomly selected. Each tooth was radiographed with RVG through a buccolingual and mesiodistal direction, and then scanned with micro-CT and reconstructed. The classifications of the root canal types according to Vertucci's type with the two methods were compared.
  
  
  RESULTS
  The canal patterns were classified as type I (67%), type III (3%), type V (18%), type VII (2%), additional type (10%) with micro-CT and canal patterns as type I (71%), type III (2%), type V (23%), type VII (1%), additional type (3%) with RVG. 63% of teeth showed one canal in both micro-CT and RVG. Only 25% of teeth were diagnosed as complex canal by the same canal type in both micro-CT and RVG. The Kappa value between micro-CT and RVG was 0.541 which suggested that the two kinds of methods had intermediate consistency. 82.8% of the premolars with root groove had two or more than two canals.
  
  
  CONCLUSIONS
  Although RVG can basically reflect the root canal system type of the mandibular first premolars in vitro, it offers poor accuracy images to complex root canals. Micro-CT three-dimensional images could clearly and precisely display the root canal system morphology of the mandibular first pre-molars in vitro.
authors.affiliation: Dept. of Stomatology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, China.
authors.forename: Xiangjie
authors.initials: X
authors.lastname: Li
authors.forename: Na
authors.initials: N
authors.lastname: Liu
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
authors.forename: Zhengmou
authors.initials: Z
authors.lastname: Dong
authors.forename: Luchuan
authors.initials: L
authors.lastname: Liu
authors.forename: Manjing
authors.initials: M
authors.lastname: Deng
mesh_terms: D001641:Bicuspid; D003786:Dental Pulp Cavity; D006801:Humans; D008334:Mandible; D008963:Molar; D012390:Root Canal Therapy; D014092:Tooth Root; D055114:X-Ray Microtomography