Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-03-28T17:43:23Z No. of bitstreams: 1 ROBERTA_LIMEIRA_FULGINITI_DIS.pdf: 824780 bytes, checksum: cdd50474d9d72a6f2df648cd97299b29 (MD5) / Approved for entry into archive by Tatiana Lopes (tatiana.lopes@pucrs.br) on 2018-04-12T11:38:51Z (GMT) No. of bitstreams: 1 ROBERTA_LIMEIRA_FULGINITI_DIS.pdf: 824780 bytes, checksum: cdd50474d9d72a6f2df648cd97299b29 (MD5) / Made available in DSpace on 2018-04-12T11:42:43Z (GMT). No. of bitstreams: 1 ROBERTA_LIMEIRA_FULGINITI_DIS.pdf: 824780 bytes, checksum: cdd50474d9d72a6f2df648cd97299b29 (MD5) Previous issue date: 2016-11-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The purpose of this study was to evaluate the influence of Co-Cr dental casting alloys presenting distinct melting ranges for compound casting technique, with lower and higher melting temperature, on the marginal adaptation of prefabricated cast-to implant cylinders for implant support prosthesis. Two cobalt-chromium base metal alloys were cast to prefabricated Co-Cr cast-to implant cylinders. The cylinders were placed in the abutments and mounted in epoxy resin. Three groups were formed according with base alloy. Group 1: Cylinder as manufactured (Control); Group 2: lower melting temperature alloy; Group 3: higher melting temperature alloy. The specimens were ground to their central portion longitudinally by a surface grinding machine, polished and evaluated by optical and scanning electron microscopy. The images were analyzed and the misfit areas between the cylinders and abutments were, if present, measured. For statistical evaluation of misfit areas ANOVA multivariate analysis and Tukey tests were used. Pre-fabricated cast-to cylinders which received higher melting temperature alloy showed significant differences in terms of marginal misfit. No significant differences were observed comparing the control and the lower melting temperature alloy group. Co-Cr casting alloy with a higher melting temperature cast on prefabricated Co-Cr implant cylinders might induce greater marginal misfit areas. The selected alloy for compound casting must not exceed the melting temperature of prefabricated implant cylinder base as recommended by manufactures. / O objetivo desde estudo foi analisar se os diferentes pontos de fus?o de ligas de cobalto-cromo (Co-Cr) para sobrefundi??o podem influenciar na adapta??o marginal de cilindros pr?-fabricados para pr?tese implantossuportada. Duas ligas met?licas de Co-Cr com pontos de fus?o distintos indicados pra t?cnica de sobrefundi??o foram fundidas aos cilindros pr?-fabricados com base de Co-Cr. As amostras foram confeccionadas, fixando os cilindros aos pilares e embutidas em resina ep?xi, formando tr?s grupos de acordo com a liga utilizada. Grupo 1: controle (cilindros de f?brica); Grupo 2: liga de Co-Cr com menor ponto de fus?o (LMT); Grupo 3: liga de Co-Cr com maior ponto de fus?o (HMT). As amostras foram seccionadas longitudinalmente na por??o central do conjunto por uma m?quina de precis?o, polidas e encaminhadas para avalia??o por microscopia eletr?nica de varredura ?ptica. As imagens foram analisadas e verificadas a presen?a de desadapta??es. Cada ?rea de desadapta??o entre cilindro e pilar foram medidas. Os resultados demonstraram signific?ncia (p<0.005) para o grupo em que os cilindros pr?-fabricados foram sobrefundidos com a liga de maior ponto de fus?o apresentando ?reas de desadapta??o marginal ao pilar. O grupo HMT demonstrou valores m?dios para ?rea de 2,489 ?m2 (?1,073), o grupo LMT de 1,536 ?m2 (? 0,375) e enquanto o grupo controle de 1,272 ?m2 (? 0,577). Para as medidas de estabilidade dimensional n?o foram observadas diferen?as estat?sticas (p>0.005) entre os grupos experimentais. Contudo, indica-se que para sobrefundi??o de cilindros pr?-fabricados a liga met?lica utilizada n?o deve possuir ponto de fus?o acima do preconizado pelo fabricante do cilindro.

Made available in DSpace on 2014-12-17T15:43:52Z (GMT). No. of bitstreams: 1 DaniloGBF_DISSERT.pdf: 1485726 bytes, checksum: 4640fbe2db551567fc003e0585ff8950 (MD5) Previous issue date: 2013-03-22 / The aim of this study was to compare the misfit vertical, horizontal and passivity of zirconia and cobalt-chromium frameworks fabricated for CAD / CAM technology and conventional method of casting. Sixteen frameworks in one-piece, were obtained from a metallic matrix containing three Br?nemark compatible implants with regular platform (Titamax Cortical Ti, Neodent). Eight frameworks were fabricated by CAD / CAM system (NeoShape, Neodent): four in zirconia (ZirCAD) and four cobalt-chromium (CoCrcad). Eight other frameworks were obtained by conventional casting method: four cobalt-chromium with UCLA abutment premachined Co-Cr (CoCrUCci) and four cobalt-chromium with UCLA abutment castable (CoCrUCc). The fit vertical, horizontal and passivity by one-screw test were measured using scanning electron microscopy with magnification of 250x. Initially evaluated the passivity by one-screw test and subsequently to assess the vertical and horizontal misfit, tightened all the screws with a torque of 20 Ncm. Mean, standard deviation, minimum and maximum values were calculated for each group. Measurements of horizontal misfit were transformed into cumulative frequency for categorization of the variable and the group later comparison groups. To evaluate the existence of quantitative differences between the groups tested for vertical misfit and passivity, we used the Kruskal-Wallis test. The Mann-Whitney test was used to compare group to group statistical differences (p <0.05). Were observed the respective mean and standard deviation for vertical misfit and passivity in micrometers: ZirCAD (5.9 ? 3.6, 107.2 ? 36), CoCrcad (1.2 ? 2.2, 107.5 ? 26 ), CoCrUCci (11.8 ? 9.8, 124.7 ? 74), CoCrUCc (12.9 ? 11.0, 108.8 ? 85). There were statistical differences in measures of vertical misfit (p = 0.000). The Mann-Whitney test revealed statistical differences (p <0.05) between all groups except between CoCrUCci and CoCrUCc (p = 0.619). No statistical difference was observed for the passivity. In relation to the horizontal misfit groups ZirCAD and CoCrcad did not show best values in relation to CoCrUCci and CoCrUCc. Based on the results it can be concluded that frameworks fabricated by CAD / CAM technology had better values of vertical fit than those manufactured by the casting method, nevertheless, the passivity was not influenced by manufacturing technique and material used. The horizontal fit obtained by frameworks manufactured by CAD / CAM was not superior to those manufactured by casting. A lower variability in vertical adjustment and passivity was observed when frameworks were fabricated by CAD / CAM technology / O objetivo deste estudo foi comparar o desajuste vertical, horizontal e a passividade de infraestruturas fabricadas em zirc?nia e cobalto-cromo por tecnologia CAD/CAM e pelo m?todo da fundi??o convencional. Dezesseis infraestruturas em monobloco, foram obtidas a partir de uma matriz met?lica contendo tr?s implantes Br?nemark compat?veis de plataforma regular (Titamax Cortical Ti, Neodent). Oito infraestruturas foram confeccionadas pelo sistema CAD/CAM (NeoShape, Neodent): quatro em zirc?nia (Zircad) e quatro em cobalto-cromo (CoCrcad). Outras oito infraestruturas foram obtidas pelo m?todo da fundi??o convencional: quatro em cobalto-cromo com pilar UCLA cinta Co-Cr (CoCrUCci) e quatro em cobalto-cromo com pilar UCLA calcin?vel (CoCrUCc). O ajuste vertical, horizontal e a passividade pelo teste do parafuso ?nico foram mensurados usando microscopia eletr?nica de varredura com aumento de 250x. Inicialmente avaliou-se a passividade pelo teste do parafuso ?nico e posteriormente para avaliar o desajuste vertical e horizontal, apertou-se todos os parafusos, com torque de 20Ncm. M?dia, desvio padr?o, valor m?nimo e m?ximo foram calculados para cada grupo. As medidas de desajuste horizontal foram transformadas em frequ?ncia cumulativa para categoriza??o da vari?vel e posterior compara??o grupos a grupo. Para avaliar a exist?ncia de diferen?as quantitativas entre os grupos testados para desajuste vertical e passividade, foi usado o teste Kruskal-Wallis. O teste Mann-Whitney foi usado para comparar as diferen?as estat?sticas grupo a grupo (p<0,05). Foram observados os respectivos valores de m?dia e desvio padr?o em micr?metros para desajuste vertical e passividade: Zircad (5,9 ? 3,6; 107,2? 36), CoCrcad (1,2 ? 2,2; 107,5? 26), CoCrUCci (11,8 ? 9,8; 124,7? 74), CoCrUCc (12,9 ? 11,0; 108,8? 85). Observaram-se diferen?as estat?sticas para medidas de desajuste vertical (p=0,000). O teste Mann-Whitney revelou diferen?as estat?sticas (p<0,05) entre todos os grupos, exceto entre CoCrUCci e CoCrUCc (p=0,619). Nenhuma diferen?a estat?stica foi observada para a passividade das infraestruturas. Em rela??o ao desajuste horizontal, os grupos ZirCAD e CoCrcad n?o apresentaram melhores valores em rela??o a CoCrUCci e CoCrUCc. Baseado nos resultados pode-se concluir que infraestruturas confeccionadas por tecnologia CAD/CAM obtiveram melhores valores de ajuste vertical que aquelas fabricadas pelo m?todo da fundi??o, apesar disso, a passividade das infraestruturas n?o foi influenciada pela t?cnica de fabrica??o e material utilizado. O ajuste horizontal obtido pelas infraestruturas fabricadas por CAD/CAM n?o foi superior ?quelas fabricadas por fundi??o. Uma menor variabilidade no ajuste vertical e na passividade foi observada quando infraestruturas foram fabricadas por tecnologia CAD/CAM