title: Three-dimensional analysis of the pulp cavity on surface models of molar teeth, using X-ray micro-computed tomography.
abstract: OBJECTIVE
  The purpose of this study was to investigate the scanning and segmentation precision of surface models of molars for the detection of small volumes, such as the reduced pulp cavity; formation of mineral deposits; detection of narrow root canals and to improve the clinical and morphological understanding of the number of root canals and their configuration.
  
  
  METHODS
  Eighteen human molars were scanned using X-ray micro-computed tomography. The reconstruction of the surface models had a precision of <1 voxel, using three-dimensional software and quantitative color mapping. In order to relate the measurements to changes over time the size of the pulp chambers was classified in two well-defined groups.
  
  
  RESULTS
  The mineral deposits were more evenly distributed in small pulp chambers than in large, but complete root canal calcification was never observed. No difference was observed in the material with respect to the presence of intra-radicular connections. In upper molars, a second mesiobuccal canal (mb(2)) frequency of 91% was found. The difference in length between the first mesiobuccal canal (mb(1)) and mb(2) was <1 mm. The number of root canals could be related to the number of root cones.
  
  
  CONCLUSIONS
  In summary, three-dimensional surface models were made with a high precision; an increased accumulation of mineral deposits was noted in molars with small pulp chambers and combined with the consistent pattern of intra-radicular connections, the potential endodontic treatment complexity is underlined in such cases. Finally, an improved understanding of root canal prevalence was reached, when merging well-defined definitions on root morphology and clinical classification systems.
authors.affiliation: Department of Cariology and Endodontics, School of Dentistry, University of Copenhagen, Copenhagen, Denmark. merma@sund.ku.dk
authors.forename: Merete
authors.initials: M
authors.lastname: Markvart
authors.forename: Lars
authors.initials: L
authors.lastname: Bjørndal
authors.forename: Tron A
authors.initials: TA
authors.lastname: Darvann
authors.forename: Per
authors.initials: P
authors.lastname: Larsen
authors.forename: Michel
authors.initials: M
authors.lastname: Dalstra
authors.forename: Sven
authors.initials: S
authors.lastname: Kreiborg
mesh_terms: D002118:Calcium / Q000032:analysis; D003116:Color; D003786:Dental Pulp Cavity / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008953:Models, Anatomic; D003765:Models, Dental; D008963:Molar / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D009811:Odontometry; D023861:Photography, Dental; D015203:Reproducibility of Results; D014074:Tooth Calcification; D014092:Tooth Root / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D055114:X-Ray Microtomography
chemical_list: D002118:Calcium