title: Evaluation of fit of zirconia posterior bridge structures constructed with different scanning methods and preparation angles.
abstract: This study evaluated the influence of scanning method, abutment position, and preparation angle on the vertical seal of three-unit posterior zirconia structures. Sixty differently angled metallic models were machined to receive 30 bridge frameworks. For each preparation type, half of the structures were waxed-up and digitized, whereas the other half were computer-designed after the abutments were scanned. Once milled, the samples were cemented in standard fashion. Misfit was assessed by scanning electron microscopy. Three-way analysis of variance showed significant differences. Computer-designed structures achieved the highest accuracy (P < 0.0001). No significant differences were recorded concerning the abutment position and convergence angle. All discrepancy values were within the clinically acceptable range.
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Complutense University of Madrid, U.C.M. Pza. Ramón y Cajal s/n, 28040 Madrid, Spain. raquel.castillo@odon.ucm.es
authors.forename: Raquel C
authors.initials: RC
authors.lastname: Oyagüe
authors.forename: M Isabel
authors.initials: MI
authors.lastname: Sánchez-Jorge
authors.forename: Andrés
authors.initials: A
authors.lastname: Sánchez Turrión
mesh_terms: D002484:Cementation / Q000379:methods; D017076:Computer-Aided Design; D003442:Crowns; D000044:Dental Abutments; D018772:Dental Marginal Adaptation; D003776:Dental Porcelain / Q000737:chemistry*; D003779:Denture Design; D003829:Denture, Partial; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007834:Lasers; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D019231:Tooth Preparation, Prosthodontic / Q000379:methods*; D014885:Waxes / Q000737:chemistry; D015036:Zinc Phosphate Cement / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry*
chemical_list: D014885:Waxes; D003776:Dental Porcelain; D015036:Zinc Phosphate Cement; D015040:Zirconium; C028541:zirconium oxide