title: Stress Over Implants of One-Piece Cast Frameworks Made With Different Materials.
abstract: This study aims to compare stress transmitted to implants and passive fit of one-piece cast frameworks fabricated with 3 different materials: commercially pure titanium (G1-CP Ti), cobalt-chromium alloy (G2-Co-Cr), and nickel-chromium-titanium alloy (G3-Ni-Cr-Ti). In total, 12 frameworks simulating bars for fixed prosthesis in a model with 5 implants were fabricated. The passive fit of the framework interface was measured using an optical microscope and the stresses transmitted to implants were measured using quantitative photoelastic analysis. Data were statistically analyzed by analysis of variance (ANOVA) and least significant difference (LSD) tests (α = 0.05). Mean and standard deviation values of passive fit and stress over implants are presented, respectively: G1 [472.49 (109.88) μm and 11.38 (9.23) KPa], G2 [584.84 (120.20) μm and 15.83 (9.30) KPa], and G3 [462.70 (179.18) μm and 16.39 (9.51) KPa]. For stress over implants, there were significant differences between G1, G2, and G3 (P = 0.035), being the lowest values for the G1. There were no significant differences for passive fit between G1 and G3 (P = 0.844), but both were statistically different from G2 (P = 0.028 and P = 0.035, respectively), which showed the worse results. It may be concluded that the stress over implants was affected by the tested materials. The CP Ti presented the best values for the evaluated items.
authors.affiliation: *Department of Dentistry, School of Dentistry, Federal University of Rio Grande do Norte-UFRN, Natal, Rio Grande do Norte †Department of Dental Implants of Latin American Institute for Dental Research and Education-ILAPEO, Curitiba, Paraná ‡Department of Dentistry, School of Dentistry, State University of Rio Grande do Norte, Caicó, Rio Grande do Norte §Department of Fixed Prosthodontics, Occlusion and Dental Materials, School of Dentistry, Federal University of Uberlândia-UFU, Uberlândia, Minas Gerais ||Department of Dental Materials and Prosthesis, School of Dentistry of Ribeirão Preto, University of São Paulo-USP, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Gustavo Augusto Seabra
authors.initials: GA
authors.lastname: Barbosa
authors.forename: Sérgio Rocha
authors.initials: SR
authors.lastname: Bernardes
authors.forename: Danilo Gonzaga Bernardo
authors.initials: DG
authors.lastname: de França
authors.forename: Flávio Domingues
authors.initials: FD
authors.lastname: das Neves
authors.forename: Maria da Glória Chiarello
authors.initials: Mda G
authors.lastname: de Mattos
authors.forename: Ricardo Faria
authors.initials: RF
authors.lastname: Ribeiro
mesh_terms: D000497:Alloys / Q000737:chemistry; D002858:Chromium Alloys / Q000737:chemistry; D003722:Dental Alloys / Q000737:chemistry*; D003734:Dental Casting Investment / Q000737:chemistry; D003735:Dental Casting Technique; D015921:Dental Implants; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry*; D019094:Dental Prosthesis, Implant-Supported; D006801:Humans; D008422:Materials Testing; D008859:Microscopy, Polarization; D011897:Random Allocation; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D000497:Alloys; D002858:Chromium Alloys; D003722:Dental Alloys; D003734:Dental Casting Investment; D015921:Dental Implants; D003764:Dental Materials; C013616:nitinol; D014025:Titanium