Dimorvan Bordin1,2, Lukasz Witek2, Vinícius P Fardin3, Estevam A Bonfante3, Paulo G Coelho2,4. 1. Prosthodontic and Periodontology Department, Piracicaba Dental School, University of Campinas, Piracicaba, Brazil. 2. Department of Biomaterials and Biomimetics, College of Dentistry, New York University, New York, NY. 3. Department of Prosthodontics, Bauru College of Dentistry, University of São Paulo, Bauru, Brazil. 4. Hansjörg Wyss Department of Plastic Surgery, New York University School of Medicine, New York, NY.
Abstract
PURPOSE: To evaluate the reliability of narrow diameter dental implants (NDIs) with similar macrogeometry and 3 implant-abutment connection designs. MATERIALS AND METHODS: Eighty-four NDIs (3.5 × 10 mm) were selected and divided into 4 groups (n = 21/group) according to implant-abutment connection design, as follows: EH - external hexagon, IH - internal hexagon, IC - internal conical, and IC-M - internal conical connected to a monolithic titanium abutment. Identical abutments were torqued to the implants, and standardized maxillary incisor crowns were cemented and subjected to step-stress accelerated life testing (SSALT) in water. Use of level probability Weibull curves, and reliability for a mission of 50,000 cycles at 75 N and 200 N were calculated. RESULTS: The beta (β) values were: 1.48 for IC, 1.40 for IC-M, 8.54 for EH, and 1.98 for IH, indicating that damage accumulation was an acceleration factor for failure of all groups. At 75 N the probability of survival was not significantly different between groups. A decrease in reliability was observed for all groups at 200 N with no significant differences between IC (81.71%) and IC-M (94.28%), or between EH and IH (0%) which presented the lowest values. EH failures were primarily restricted to the screw, while IH involved screw and implant fracture. IC and IC-M were restricted to prosthetic failures (fracture and bending). CONCLUSIONS: Narrow implants with external or internal hexagon connections presented the lowest reliability at high loads compared to internal conical connections. Failure modes differed among connections.
PURPOSE: To evaluate the reliability of narrow diameter dental implants (NDIs) with similar macrogeometry and 3 implant-abutment connection designs. MATERIALS AND METHODS: Eighty-four NDIs (3.5 × 10 mm) were selected and divided into 4 groups (n = 21/group) according to implant-abutment connection design, as follows: EH - external hexagon, IH - internal hexagon, IC - internal conical, and IC-M - internal conical connected to a monolithic titanium abutment. Identical abutments were torqued to the implants, and standardized maxillary incisor crowns were cemented and subjected to step-stress accelerated life testing (SSALT) in water. Use of level probability Weibull curves, and reliability for a mission of 50,000 cycles at 75 N and 200 N were calculated. RESULTS: The beta (β) values were: 1.48 for IC, 1.40 for IC-M, 8.54 for EH, and 1.98 for IH, indicating that damage accumulation was an acceleration factor for failure of all groups. At 75 N the probability of survival was not significantly different between groups. A decrease in reliability was observed for all groups at 200 N with no significant differences between IC (81.71%) and IC-M (94.28%), or between EH and IH (0%) which presented the lowest values. EH failures were primarily restricted to the screw, while IH involved screw and implant fracture. IC and IC-M were restricted to prosthetic failures (fracture and bending). CONCLUSIONS: Narrow implants with external or internal hexagon connections presented the lowest reliability at high loads compared to internal conical connections. Failure modes differed among connections.
Authors: María Prados-Privado; José Antonio Bea; Rosa Rojo; Sérgio A Gehrke; José Luis Calvo-Guirado; Juan Carlos Prados-Frutos Journal: Appl Bionics Biomech Date: 2017-07-05 Impact factor: 1.781
Authors: Eugenio Velasco-Ortega; Antonio Flichy-Fernández; Miquel Punset; Alvaro Jiménez-Guerra; José María Manero; Javier Gil Journal: Materials (Basel) Date: 2019-11-12 Impact factor: 3.623
Authors: Edmara T P Bergamo; Everardo N S de Araújo-Júnior; Adolfo C O Lopes; Paulo G Coelho; Abbas Zahoui; Ernesto B Benalcázar Jalkh; Estevam A Bonfante Journal: Biomed Res Int Date: 2020-09-07 Impact factor: 3.411