ABSTRACT
Objetivo: avaliar, in vitro, a dureza superficial e profunda de dois tipos diferentes de resina composta, quandoem contato com o cimento de óxido de zinco e eugenol (IRM®). Métodos: foram selecionadas as resinasCharisma® e Vittra® e confeccionados 80 corpos de prova, sendo 40 para cada marca de compósito, queforam divididos em oito grupos (n=10) conforme o contato (imediato, 7 dias, 14 dias) ou não (grupo controle)com o eugenol. Colocou-se num pote dappen uma porção de IRM e um espécime de resina pronto, que,após a presa do material restaurador temporário e a remoção do exemplar colocado, gerou o molde pararealização das amostras em contato com o eugenol, sendo armazenado em água em temperatura ambiente,para os subgrupos 7 e 14 dias. Em sequência, foi inserido um único incremento de resina composta e polimerizadopor 40 segundos, gerando os espécimes que foram armazenados em local seco para serem submetidosao teste de microdureza Vickers sob uma carga de 300 gramas, com tempo de penetração de 10 segundos.Os dados obtidos foram analisados pelo teste ANOVA, a um nível de significância de p<0,05. Resultados:somente o grupo da resina Charisma® que teve contato imediato com eugenol não atingiu 80% de durezaprofunda em relação à superficial. Entretanto, para todos os grupos analisados, tanto a dureza superficialquanto a profunda aumentaram após o contato com o eugenol em relação ao grupo controle. Conclusão: oeugenol não influenciou negativamente a dureza das resinas compostas.(AU)
Objective: to evaluate, in vitro, the superficial and deep hardness of two different types of composite resin when in contact with zinc oxide eugenol cement (IRM). Method: Charisma® and Vittra® resins were selected and 80 specimens were made, 40 for each composite brand that were divided into eight groups (n = 10) according to contact (immediate, 7 days, 14 days) or no (control group) with eugenol. A portion of IRM and a ready-made resin specimen were placed in a dappen pot, which after setting the temporary restorative material and removing the placed specimen, generated the template for making the samples in contact with eugenol, being stored in water in room temperature for subgroups 7 and 14 days. In sequence, a single increment of composite was inserted and polymerized resin for 40 seconds, generating specimens that were stored in a dry place to be submitted to the Vickers microhardness test under a load of 300 grams, with a penetration time of 10 seconds. The data obtained were analyzed by the ANOVA test, at a significance level of p <0.05. Results: only the Charisma® resin group that had immediate contact with eugenol did not reach 80% deep hardness in relation to superficial hardness. However, for all groups analyzed, both superficial and deep hardness increased after contact with eugenol compared to the control group. Conclusion: eugenol did not negatively influence the hardness of composite resins.(AU)
Subject(s)
Zinc Oxide-Eugenol Cement/chemistry , Composite Resins/chemistry , Hardness , Reference Values , Surface Properties , Time Factors , Analysis of Variance , Hardness TestsABSTRACT
Background: The purpose of this study was to investigate the behavior of a resin-based 2,2-bis (p-[2′-hydroxy-3′-methacryloxypropoxy] phenylene) propane and a composite resin modified with oxirane, regarding the ability of marginal sealing, both with direct restorations and indirect restorations. Materials and Methods: To achieve this, mesio- and disto-occlusal cavities were made on the same tooth, totalling 100 cavities. These cavities were restored with two materials, Filtek P90 (3M ESPE) and Opallis (FGM). Then, they were divided into two groups: Fifty direct restorations, each sample restored with the two materials, following the manufacturer's protocol and fifty indirect restorations, and then cemented with a paste obtained by diluting the resin in its adhesive. The templates were thermally cycled, 30 s at 5°C and 30 s at 55°C for 500 cycles and then were immersed in methylene blue for 24 h. Afterward, they were trimmed using a plaster trimmer from occlusal toward a gingival direction. These samples were analyzed with stereomicroscope (×3) by two blinded observers. Then, a system which considers the average number of surrounding walls that have suffered infiltration on a scale of 0–3 was used. Results: Data were subjected to statistical analysis (Mann–Whitney and Kruskal–Wallis tests) with a significance level of 5% maximum. Conclusion: It was concluded that the indirect restorations showed the greatest number of restorations with score 0 and 1 (34) and lowest score 2 and 3 (16). This suggests that indirect restorations regardless of the material used behaved more effectively regarding the marginal sealing of restorations.