The effect of DLC-coating deposition method on the reliability and mechanical properties of abutment's screws

Autor(es)

Bordin, Dimorvan ^[1] ; Coelho, Paulo G. ^{[2, 3]} ; Bergamo, Edmara T. P. ^[4] ; Bonfante, Estevam A. ^[5] ; Witek, Lukasz ^[2] ; Del Bel Cury, Altair A. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Guarulhos, Dept Restorat Dent, Guarulhos, SP - Brazil

^[2] NYU, Coll Dent, Dept Biomat & Biomimet, New York, NY - USA

^[3] NYU, Hansjorg Wyss Dept Plast Surg, Langone Med Ctr, 550 First Ave, New York, NY 10016 - USA

^[4] Univ Estadual Campinas, Piracicaba Dent Sch, Dept Prosthodont & Periodontol, Piracicaba, SP - Brazil

^[5] Univ Sao Paulo, Bauru Sch Dent, Dept Prosthodont & Periodontol, Bauru, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Dental Materials; v. 34, n. 6, p. E128-E137, JUN 2018.
• Citações Web of Science: 1

Resumo

Objective. To characterize the mechanical properties of different coating methods of DLC (diamond-like carbon) onto dental implant abutment screws, and their effect on the probability of survival (reliability). Methods. Seventy-five abutment screws were allocated into three groups according to the coating method: control (no coating); UMS-DLC applied through unbalanced magnetron sputtering; RFPA-DLC applied through radio frequency plasma-activated (n = 25/group). Twelve screws (n=4) were used to determine the hardness and Young's modulus (YM). A 3D finite element model composed of titanium substrate, DLC-layer and a counterpart were constructed. The deformation (jtm) and shear stress (MPa) were calculated. The remaining screws of each group were torqued into external hexagon abutments and subjected to step-stress accelerated life-testing (SSALT) (n =21/group). The probability Weibull curves and reliability (probability survival) were calculated considering the mission of 100, 150 and 200N at 50,000 and 100,000 cycles. Results. DLC-coated experimental groups evidenced higher hardness than control (p <0.05). In silico analysis depicted that the higher the surface Young's modulus, the higher the shear stress. Control and RFPA showed p<1, indicating that failures were attributed to materials strength; UMS showed beta>1 indicating that fatigue contributed to failure. High reliability was depicted at a mission of 100 N. At 200 N a significant decrease in reliability was detected for all groups (ranging from 39% to 66%). No significant difference was observed among groups regardless of mission. Screw fracture was the chief failure mode. Significance. DLC-coating have been used to improve titanium's mechanical properties and increase the reliability of dental implant-supported restorations. (C) 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved. (AU)

• Processo FAPESP: 16/18818-8 - EMU concedido no processo 2012/19078-7: ElectroPuls E3000 Linear-Torsion All-Electric dynamic test instrument package
• Beneficiário: Estevam Augusto Bonfante
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 12/19078-7 - Desenvolvimento e processamento de compósito de Al2O3-ZrO2 para próteses monolíticas CAD/CAM: efeito do envelhecimento na resistência à flexão biaxial
• Beneficiário: Estevam Augusto Bonfante
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores