EFEITO DO TRATAMENTO SUPERFICIAL EM LIMAS DE NITI SUBMETIDOS A CARREGAMENTO EM TORÇÃO / THE EFFECT OF SURFACE ON NITI FILES SUBJECTED TO TORSION LOADING
AUTOR(ES)
JULIO CESAR DE AZEVEDO CARVALHAL
DATA DE PUBLICAÇÃO
2004
RESUMO
NiTi Profile® 25/.04 files do not undergo surface polishing treatments after machining, and therefore exhibit local stress concentrators and, consequently, areas of cracking and fractures. The effect of different surface conditions on the torsional strength of endodontic files were evaluated. 18 NiTi Profile® 25/.04 rotary files were examined by scanning electron. A group of 6 files (Group I) were not subjected to any chemical treatment, another group of 6 (Group II) were treated for 2 minutes using a solution of 8% Nitric Acid, 4% Flouridic Acid, and a further 6 (Group III) were treated with the same solution fot 2.5 minutes. All the file, with and without treatment, were loaded in a torsion test and fractography of the samples was undertaken by scanning electron microscopy. The variables investigated were, torque at fracture and maximum angle of rotation at fracture. The results obtained in these mechanical tests were subjected to a statistical analysis utilizing the T-Student test. It can be concluded from these results that there was a statistically significant difference between the maximum torque results for groups II and III, and between the maximum angle results for groups I and III.
ASSUNTO(S)
scanning electron microscopy microscopia eletronica de varredura torcao rotary niti instruments instrumentos rotatorios de niti propriedades mecanicas mechanical properties torsion
ACESSO AO ARTIGO
Documentos Relacionados
- Sobre a otimização de estruturas submetidas a carregamento dinâmico.
- Efeitos da n-acetilcisteína em testículos de ratos submetidos a torção do cordão espermático
- Efeito do tratamento superficial na devitrificação e dissolução da silica vitrea
- The fracture evaluation of NiTi SMA endodontics files
- Resistência à fadiga e comportamento em torção de instrumentos endodônticos de NiTi Profile