title: SEM evaluation of the precision of fit of CAD/CAM zirconia and metal-ceramic posterior crowns.
abstract: The purpose of this study is to evaluate the precision of fit of posterior crowns made from three commercial CAD/CAM zirconia ceramics and conventional metal-ceramic technique. The external and internal marginal fit of the crowns was evaluated using direct SEM-based measurements. The data were subjected to Kruskal-Wallis, multicomparison post hoc analysis and Wilcoxon rank sum tests (α=0.05). Significant differences were observed for the external (p<0.002) and the internal (p<0.0001) marginal evaluation among the groups. No differences were observed between the buccal and lingual surfaces for the external (p=0.34) and internal (p=0.55) evaluations. No differences were showed between the external and internal measurements (p=0.37). The accuracy of fit was within the range of clinical acceptance. The lowest discrepancies corresponded to the NobelProcera group for external (39.3±11.81 μm) and internal (41.09±7.54 µm) marginal fit. The results confirmed that destructive methods are not required to assess the marginal fit of dental prosthetic crowns.
authors.affiliation: Department of Buccofacial Prostheses, Faculty of Odontology, University Complutense.
authors.forename: Rocio
authors.initials: R
authors.lastname: Ortega
authors.affiliation: Department of Buccofacial Prostheses, Faculty of Odontology, University Complutense.
authors.forename: Esther
authors.initials: E
authors.lastname: Gonzalo
authors.affiliation: Department of Buccofacial Prostheses, Faculty of Odontology, University Complutense.
authors.forename: Miguel
authors.initials: M
authors.lastname: Gomez-Polo
authors.affiliation: Department of Buccofacial Prostheses, Faculty of Odontology, University Complutense.
authors.forename: Carlos
authors.initials: C
authors.lastname: Lopez-Suarez
authors.affiliation: Department of Buccofacial Prostheses, Faculty of Odontology, University Complutense.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Suarez
mesh_terms: D002516:Ceramics; D017076:Computer-Aided Design; D003442:Crowns; D018772:Dental Marginal Adaptation; D003776:Dental Porcelain; D017267:Dental Prosthesis Design; D006801:Humans
chemical_list: D003776:Dental Porcelain
keywords: CAD/CAM; External marginal fit; Internal marginal fit; Measurement techniques; Zirconia