title: C-shaped canal system in mandibular second molars part IV: 3-D morphological analysis and transverse measurement.
abstract: The purpose of this study was to investigate three-dimensional (3-D) morphology of C-shaped root canal system using micro-computed tomography (microCT) and 3-D reconstruction. There were 102 extracted mandibular second molars with fused roots collected from a native Chinese population. The teeth were scanned by microCT and reconstructed by 3-D software. The 98 teeth that possessed a C-shaped canal system were further analyzed. The 3-D reconstructed images of canals were classified into three categories: merging type (type I), symmetrical type (type II), and asymmetrical type (type III). The cross-sectional images of each tooth were submitted to computer analysis, and the minimum canal wall thickness was measured. In these 98 molars, 32 (32.65%) teeth showed a merging type appearance, 38 (38.78%) a symmetrical type and 28 (28.57%) an asymmetrical type. The minimum canal wall thickness in type I was thicker than that in type II or type III in the apical and middle portion (p < 0.05). Being fully aware of the configuration of C-shaped root canal system and the location of minimum wall thickness will ensure more efficient root canal treatment.
authors.affiliation: Endodontic Center, School & Hospital of Stomatology, Wuhan University, Wuhan, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Gao
authors.forename: Bing
authors.initials: B
authors.lastname: Fan
authors.forename: Gary S P
authors.initials: GS
authors.lastname: Cheung
authors.forename: James L
authors.initials: JL
authors.lastname: Gutmann
authors.forename: Mingwen
authors.initials: M
authors.lastname: Fan
mesh_terms: D019412:Anatomy, Cross-Sectional; D002681:China; D003786:Dental Pulp Cavity / Q000002:abnormalities* / Q000000981:diagnostic imaging; D003804:Dentin / Q000002:abnormalities / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008334:Mandible; D008963:Molar / Q000002:abnormalities / Q000000981:diagnostic imaging*; D009811:Odontometry / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods; D014092:Tooth Root / Q000000981:diagnostic imaging