title: Analysis of internal defects in all-ceramic crowns using micro-focus X-ray computed tomography.
abstract: The purpose of this study was to examine all-ceramic crowns for internal defects using micro-focus X-ray computed tomography (microCT). Mono-ceramic CAD/CAM crowns, ceramic-core CAD/CAM crowns, and heat-pressed ceramic crowns were used as specimens. The microCT images of the specimens were obtained and analyzed using a 3D volume rendering software. Mono-ceramic CAD/CAM crowns contained almost no pores, while ceramic-core CAD/CAM crowns contained pores only in the porcelain veneer area. Heat-pressed ceramic crowns had lots of pores in the cusps and the area around them. Results of this study indicated that internal pores in all-ceramic crowns could be observed non-destructively using microCT, and that CAD/CAM all-ceramic crowns contained fewer pores than crowns fabricated using manual techniques.
authors: Department of Fixed Prosthodontics, Osaka University Graduate School of Dentistry, Osaka, Japan. tnakamur@dent.osaka-u.ac.jp
authors: Takashi
authors: T
authors: Nakamura
authors: Kazumichi
authors: K
authors: Wakabayashi
authors: Yoshiko
authors: Y
authors: Kawamura
authors: Soichiro
authors: S
authors: Kinuta
authors: Yoshihiko
authors: Y
authors: Mutobe
authors: Hirofumi
authors: H
authors: Yatani
mesh_terms: D002516:Ceramics / Q000737:chemistry*; D017076:Computer-Aided Design; D003442:Crowns; D007091:Image Processing, Computer-Assisted; D008838:Microcomputers; D016062:Porosity; D014057:Tomography, X-Ray Computed