title: New evaluation method by microfocus radiograph CT for 3D assessment of internal adaptation of all-ceramic crowns.
abstract: The aim of this study was to evaluate the effectiveness of the microfocus radiograph CT system in examining the adaptation of all-ceramic crowns three-dimensionally and non-destructively. The computed tomograms of the crown and abutment model were filmed by microfocus radiograph CT. Using a volumetric rendering software, images of gaps were extracted and reconstructed three-dimensionally, and their volume data analyzed. In order to compare this method with the conventional method, fitness test silicone paste was sandwiched between the abutment and all-ceramic crown. Adaptation of the crown on the abutment model was then observed non-destructively and three-dimensionally. Furthermore, the gaps could be analyzed in any arbitrary position. Concerning mean gap thickness, there was significant differences between the two measurement methods. However, it was very slight. We therefore concluded that the microfocus radiograph CT system is well positioned to be an extremely effective method in examining the adaptation of all-ceramic crowns.
authors.affiliation: Division of Oromaxillofacial Regeneration, Course for Integrated Oral Sciences and Stomatology, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871, Japan. wakaba@dent.osaka-u.ac.jp
authors.forename: Kazumichi
authors.initials: K
authors.lastname: Wakabayashi
authors.forename: Taiji
authors.initials: T
authors.lastname: Sohmura
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakamura
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kojima
authors.forename: Souichiro
authors.initials: S
authors.lastname: Kinuta
authors.forename: Junzo
authors.initials: J
authors.lastname: Takahashi
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Yatani
mesh_terms: D002516:Ceramics / Q000737:chemistry*; D003442:Crowns; D000044:Dental Abutments; D017267:Dental Prosthesis Design; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D012828:Silicones / Q000737:chemistry; D013499:Surface Properties; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D012828:Silicones