title: Stress Analysis on Single Cobalt/Chrome Prosthesis With a 15-mm Cantilever Placed Over 10/13/15-mm-length Implants: A Simulated Photoelastic Model Study.
abstract: The aim of study was to assess the stress around 10/13/15-mm implants in the mandibular area with a 15-mm cantilevered acrylic-resin-coated prostheses following the application force, using the photoelasticity method. Three photoelastic mandibular models were created containing 10-, 13-, and 15-mm implants in length and 3.75 mm in diameter. The implants had bore internal hex connections and were placed parallel to the intermental region. Abutments with 1-mm high cuffs were placed over the implants, and a single cobalt/chrome metallic prosthesis with a 15-mm cantilever, coated with thermoplastic acrylic resin, was placed on top. Loads of 1.0 and 3.0 bars were applied, and the images were photographed and assessed by photoelasticity method. The greatest stress levels were observed for the 10-mm implants. The stress pattern was the same regardless of implant length; only the magnitude of the stress along the implant body revealed changes. Increased implant length played a role in reducing stress on the investigated area of the model, and the 15-mm implants exhibited the best performance in regard to stress distribution. The highest stress levels were found in the implants closest to the cantilever and the central implant. The longest implants were more favorable in regard to the stress distribution on the peri-implant support structures in the 15-mm cantilevered prosthesis under loads.
authors.affiliation: 1  Department of Dental Prosthesis, University of São Paulo - USP, Sao Paulo, Brazil.
authors.forename: José Fábio Guastelli
authors.initials: JF
authors.lastname: Gastaldo
authors.affiliation: 2  Department of Implant Dentistry, University of Santo Amaro - UNISA, Sao Paulo, Brazil.
authors.forename: Angélica Castro
authors.initials: AC
authors.lastname: Pimentel
authors.affiliation: 1  Department of Dental Prosthesis, University of São Paulo - USP, Sao Paulo, Brazil.
authors.forename: Maria Helena
authors.initials: MH
authors.lastname: Gomes
authors.affiliation: 2  Department of Implant Dentistry, University of Santo Amaro - UNISA, Sao Paulo, Brazil.
authors.forename: Wilson Roberto
authors.initials: WR
authors.lastname: Sendyk
authors.affiliation: 1  Department of Dental Prosthesis, University of São Paulo - USP, Sao Paulo, Brazil.
authors.forename: Dalva Cruz
authors.initials: DC
authors.lastname: Laganá
mesh_terms: D003035:Cobalt; D015921:Dental Implants; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D003799:Dental Stress Analysis; D013314:Stress, Mechanical
chemical_list: D015921:Dental Implants; D003035:Cobalt
keywords: dental implants; load; mandible; stress