| Texto completo | |
| Autor(es): |
Bordin, Dimorvan
;
Bergamo, Edmara T. P.
;
Fardin, Vinicius P.
;
Coelho, Paulo G.
;
Bonfante, Estevam A.
Número total de Autores: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS; v. 71, p. 244-249, JUL 2017. |
| Citações Web of Science: | 6 |
| Resumo | |
Purpose: To assess the probability of survival (reliability) and failure modes of narrow implants with different diameters. Materials and methods: For fatigue testing, 42 implants with the same macrogeometry and internal conical connection were divided, according to diameter, as follows: narrow ((empty set)3.3x10 mm) and extra-narrow ((empty set)2.9x10 mm) (21 per group). 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. The use level probability Weibull curves, and reliability for a mission of 50,000 and 100,000 cycles at 50 N, 100, 150 and 180 N were calculated. For the finite element analysis (FEA), two virtual models, simulating the samples tested in fatigue, were constructed. Loading at 50 N and 100 N were applied 30 degrees off-axis at the crown. The von-Mises stress was calculated for implant and abutment. Results: The beta (beta) values were: 0.67 for narrow and 1.32 for extra-narrow implants, indicating that failure rates did not increase with fatigue in the former, but more likely were associated with damage accumulation and wear-out failures in the latter. Both groups showed high reliability (up to 97.5%) at 50 and 100 N. A decreased reliability was observed for both groups at 150 and 180 N (ranging from 0 to 82.3%), but no significant difference was observed between groups. Failure predominantly involved abutment fracture for both groups. FEA at 50 N-load, (empty set)3.3 mm showed higher von-Mises stress for abutment (7.75%) and implant (2%) when compared to the (empty set)2.9 mm. Conclusions: There was no significant difference between narrow and extra-narrow implants regarding probability of survival. The failure mode was similar for both groups, restricted to abutment fracture. (AU) | |
| 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 |