Caracteriza??o mec?nica, termodin?mica e qu?mica dos fios CuNiTi comerciais

• Main Author: Gonzaga, Ariane Salgado
• Other Authors: 00933226403
• Language: Portuguese
• Published: PROGRAMA DE P?S-GRADUA??O EM SA?DE COLETIVA 2017
• Subjects: CNPQ::CIENCIAS DA SAUDE::SAUDE COLETIVA; Ortodontia; Fios ortod?nticos e ortodontia corretiva
• Online Access: https://repositorio.ufrn.br/jspui/handle/123456789/23470

Submitted by Automa??o e Estat?stica ([e-mail]) on 2017-06-02T22:57:52Z No. of bitstreams: 1 ArianeSalgadoGonzaga_DISSERT.pdf: 2282293 bytes, checksum: b4f800275b25103fafccae7212157dbf (MD5) === Approved for entry into archive by Arlan Eloi Leite Silva ([e-mail]) on 2017-06-09T23:29:42Z (GMT) No. of bitstreams: 1 ArianeSalgadoGonzaga_DISSERT.pdf: 2282293 bytes, checksum: b4f800275b25103fafccae7212157dbf (MD5) === Made available in DSpace on 2017-06-09T23:29:42Z (GMT). No. of bitstreams: 1 ArianeSalgadoGonzaga_DISSERT.pdf: 2282293 bytes, checksum: b4f800275b25103fafccae7212157dbf (MD5) Previous issue date: 2017-01-30 === Introdu??o: Os fios Copper Ni-Ti (CuNiTi) possuem indica??es de uso cl?nico espec?ficas, e por esse motivo deveriam expressar as caracter?sticas mec?nicas e termodin?micas informadas pelos fabricantes. Com a queda da patente de produ??o, estes fios passaram a ser manufaturados por diversas empresas com grande varia??o de pre?o, processo de fabrica??o e possivelmente de qualidade. Objetivos: Com a finalidade de verificar as propriedades desses fios, este trabalho se prop?s a caracterizar mec?nica, termodin?mica e quimicamente fios CuNiTi comerciais. Materiais e M?todos: A amostra foi constitu?da de 40 arcos pr?-contornados, termodin?micos com adi??o de cobre, espessura de 0.017? x 0.025? com temperatura Af de 35?C, de 5 fabricantes, American Orthodontics? (G1), Eurodonto? (G2), Morelli? (G3), Ormco? (G4) e Orthometric? (G5), sendo 8 fios de cada um. Os fios foram submetidos a um teste de padroniza??o das suas dimens?es, ensaios de tra??o, MEV-EDS e ensaio de calorimetria diferencial (DSC). Devido ? pequena variabilidade inerente aos testes mec?nicos com fios, foram utilizados testes param?tricos (ANOVA OneWay e p?s teste de Tukey), considerando o n?vel de signific?ncia de 5%. Resultados: Todos os fios apresentaram dimens?es padronizadas de 0.017?x0.025?. Ao ensaio de tra??o, todos apresentaram comportamento superel?stico com taxa SE superior a 8 e as seguintes m?dias de plat? de for?a ? G1 36,49N; G2 27,34N; G3 19,24N; G4 37,54N; e G5 17,87N. No ensaio DSC, as m?dias de Af para G1 (29,40?C), G2 (29,13?C) e G3 (31,43?C), tiveram p>0,05 entre si. G4 (32,77?C) e G5 (35,17?C) apresentaram diferen?as estatisticamente significativas entre si e entre os outros grupos, com p<0,05. No ensaio MEV-EDS amostras apresentaram os elementos Ni, Ti, Cu e Al em concentra??es diferentes. Conclus?o: Todos os fios apresentam comportamento superel?stico. Os fios do grupo G5 foram os ?nicos a apresentar temperatura Af semelhante a indicada pelo fabricante. O G5 e o G3 apresentaram os menores ?ndices de plat? de for?a durante a desativa??o. O Cu ? fundamental para estabilizar a TTRs, contudo em ligas n?o equiatomicas uma maior concentra??o de Al parece ser fundamental para elevar a temperatura de transi??o. === Introduction: Copper Ni-Ti (CuNiTi) wires have indications of specific clinical use and should therefore express the mechanical and thermodynamic characteristics reported by manufacturers. With the fall of the production patent, several companies began to manufacture these wires with great variation of price, process of manufacture and possibly of quality. Objectives: In order to verify the properties of these wires, this work aims to characterize mechanically, thermodynamically and chemically CuNiTi commercial wires. Materials and Methods: The sample consisted of 40 precontoured, thermodynamic arches with addition of copper, dimensions of 0.017 "x 0.025" with Af temperature of 35?C, from 5 manufacturers, American Orthodontics? (G1), Eurodonto? (G2), Morelli? (G3), Ormco? (G4) e Orthometric? (G5), 8 wires of each one. The wires underwent a standardization test of their dimensions, tensile tests, MEV-EDS and differential scanning calorimetry (DSC) test. Due to the small variability inherent of the mechanical tests in wires, parametric tests (ANOVA OneWay and Tukey post test) were used, considering a significance level of 5%. Results: All wires presented standardized dimensions of 0.017 "x0.025". In the tensile test, all presented superelastic behavior with SE rate higher than 8 and the following means of force plateau - G1 36,49N; G2 27,34N; G3 19,24N; G4 37,54N; e G5 17,87N. In the DSC assay, the means of Af for G1 (29.40?C), G2 (29.13?C) and G3 (31.43?C), had p>0.05 relative to each other. G4 (32.77?C) and G5 (35.17?C) presented statistically significant differences between themselves and among the other groups, with p <0.05. MEV-EDS assay for all samples presented Ni, Ti, Cu and Al in different concentrations. Conclusion: All wires have superelastic behavior. G5 wires were the only ones having an Af temperature similar to that indicated by the manufacturer. G5 and G3 showed the lowest plateau means during deactivation. Cu is fundamental to stabilize the TTRs, however in non-equiatomic alloys a higher concentration of Al seems to be fundamental to raise the transition temperature.