title: [Comparison of adaptation of crowns of different lithium disilicate glass-ceramic].
abstract: OBJECTIVE
  To evaluate the adaptation of different lithium disilicate glass-ceramic crown and whether different fabrication processes affect the adaptation of crowns.
  
  
  METHODS
  Thirty epoxy dies crowns were divided into 3 groups. They were cemented to domestic lithium disilicate glass-ceramic crowns in Group A, to IPS e.max CAD crowns in Group B and to IPS e.max Press crowns in Group C respectively. All crowns were cut by cutting machine. A confocal laser scanning microscope was used to measure the gap between crown tissue surface and die.
  
  
  RESULTS
  There were significant differences in the three groups of measurement points(P<0.05). Within the groups, specimens in group A showed in the lowest marginal fit([46.8±9.1] μm). Those in group B showed the lowest shoulder suitability([59.3±7.9] μm), axial plane([50.5±3.6] μm) and occlusal surface([87.6±11.6 μm]. Those in group C demonstrated the lowest axial plane angle[(84.4±10.1) μm]. In addition to the axial plane angle, the CAD/CAM system exhibited good accuracy of fit.
  
  
  CONCLUSIONS
  The three groups of lithium disilicate glass-ceramic crowns appeared to have clinically acceptable fit.
authors.affiliation: Department of Prosthodontics, School of Stomatology, China Medical University & Liaoning Institute of Dental Research, Shenyang 110002, China.
authors.forename: Kemeng
authors.initials: K
authors.lastname: Li
authors.affiliation: Department of Prosthodontics, School of Stomatology, China Medical University & Liaoning Institute of Dental Research, Shenyang 110002, China.
authors.forename: Hongjun
authors.initials: H
authors.lastname: Ai
authors.affiliation: Department of Prosthodontics, School of Stomatology, China Medical University & Liaoning Institute of Dental Research, Shenyang 110002, China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Yi
mesh_terms: D002516:Ceramics; D017076:Computer-Aided Design; D003442:Crowns; D018772:Dental Marginal Adaptation; D003776:Dental Porcelain; D017267:Dental Prosthesis Design / Q000379:methods*; D006801:Humans; D018613:Microscopy, Confocal; D013499:Surface Properties
chemical_list: C508050:IPS e.max Press; C493120:lithia disilicate; D003776:Dental Porcelain; C023506:Glass ceramics