title: 3D morphological measurements of dental casts with occlusal relationship using microfocus X-ray CT.
abstract: In the diagnosis of dental occlusion, it is necessary to quantitatively measure interocclusal contacts and transfer them to a computer model. In this aspect, three-dimensional computer models of upper and lower dental casts play a significant role. In this study, we proposed a new method to measure occlusal interaction by using a microfocus X-ray CT technique. Measurement accuracy was determined as +/-0.03 mm in comparison with a coordinate measuring machine. A superimposition procedure for two sets of three-dimensional dental cast models was also established. Using the same dental cast, the standard deviation between the two sets of models was +/-0.015 mm - which was defined as measurement precision. Between an optical laser scanner and the microfocus X-ray CT system, the standard deviation measured between the two models was +/-0.05 mm. Data were acquired when upper and lower dental casts mounted on the bite impression were scanned, and then occlusal interaction, contacts, and distance distribution between the casts were visualized by a colored map on the cast models. Within the limitations of the current study, it was successfully demonstrated that microfocus Xray CT was well poised for quantitative measurement of occlusal interaction.
authors.affiliation: Department of Medical Simulation Engineering, Research Center for Nano Medical Engineering, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8507, Japan. kamegawa@shimadzu.co.jp
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kamegawa
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakamura
authors.forename: Sadami
authors.initials: S
authors.lastname: Tsutsumi
mesh_terms: D002508:Cephalometry / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation / Q000379:methods*; D007574:Jaw Relation Record / Q000295:instrumentation / Q000379:methods; D008310:Malocclusion / Q000175:diagnosis*; D008852:Microradiography; D003765:Models, Dental; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed