title: The effect of framework design on fracture resistance of metal-ceramic implant-supported single crowns.
abstract: This study evaluated the effect of framework design on the fracture resistance of metal-ceramic implant-supported crowns. Screw-retained molar crowns with a screw access hole composed of metal or porcelain were compared to a cement-retained crown (control). For each group (n = 10), five crowns were subjected to dynamic loading (1,200,000 x 100 N x 2 Hz at 37 degrees C). Afterward, all specimens were loaded to failure using a universal testing machine. Significant differences could be established between the cement- and screw-retained groups (P = or < .05), but no difference was found between the screw-retained groups and the specimens subjected to dynamic loading. Occlusal discontinuity of screw-retained crowns affects their resistance, and the metallic support on the screw access hole did not reinforce the crowns.
authors.affiliation: Department of Prosthodontics, Bauru School of Dentistry, University of São Paulo, Brazil. zezogoes@uol.com.br
authors.forename: José Luiz G
authors.initials: JL
authors.lastname: de Oliveira
authors.forename: Leandro Moura
authors.initials: LM
authors.lastname: Martins
authors.forename: Jeffeson
authors.initials: J
authors.lastname: Sanada
authors.forename: Pedro Cesar G
authors.initials: PC
authors.lastname: de Oliveira
authors.forename: Accácio L
authors.initials: AL
authors.lastname: do Valle
mesh_terms: D003188:Composite Resins / Q000737:chemistry; D003442:Crowns; D000044:Dental Abutments; D003738:Dental Cements / Q000737:chemistry; D015921:Dental Implants; D003776:Dental Porcelain / Q000737:chemistry*; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D019094:Dental Prosthesis, Implant-Supported; D003799:Dental Stress Analysis / Q000295:instrumentation; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D016876:Metal Ceramic Alloys / Q000737:chemistry*; D019279:Resin Cements / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D015040:Zirconium / Q000737:chemistry
chemical_list: D003188:Composite Resins; D003738:Dental Cements; D015921:Dental Implants; D005899:Glass Ionomer Cements; D016876:Metal Ceramic Alloys; D019279:Resin Cements; C084550:Vitremer; C083568:Z100 composite resin; D003776:Dental Porcelain; D012822:Silicon Dioxide; D015040:Zirconium