A carregar...
Publicação
Microdureza e resistência à flexão de resinas CAD-CAM submetidas a envelhecimento térmico
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 1.77 MB | Adobe PDF |
Autores
Resumo(s)
Objetivo: O objetivo deste estudo in vitro foi avaliar a microdureza e a resistência à flexão, de resinas utilizadas para a confeção de bases de próteses dentárias, produzidas pelo método CAD-CAM de impressão 3D e submetidas a processos de envelhecimento térmico.
Materiais e métodos: Um total de 32 espécimes retangulares (4x10x3,3 mm) foram fabricados, formando grupos (n=8) de duas resinas fotopolimerizáveis de impressão 3D (V- Print Dentbase e Denture 3D+) e duas resinas termopolimerizáveis convencionais (Probase Hot e Villacryl H Rapid FN). Todos os espécimes foram sujeitos a um envelhecimento térmico que consistiu em 1000 ciclos de oscilações térmicas entre os 5ºC e os 55ºC. Foi realizada a medição da microdureza com uma ponta Knoop e a medição da resistência à flexão em 3 pontos.
Resultados: Foram encontradas diferenças estatisticamente significativas entre as resinas estudadas nos valores de microdureza inicial (p<0,001), após o envelhecimento térmico (p<0,001) e nos valores de resistência à flexão (p<0,001). Os valores de microdureza foram superiores para os grupos das resinas termopolimerizáveis convencionais antes e após o envelhecimento térmico. No grupo da resina impressa V-Print Dentbase, quando comparados os dois tempos de medição da microdureza, não foram observadas diferenças estatisticamente significativas (p=0,064). Nos restantes grupos, os valores de microdureza foram inferiores após o envelhecimento térmico (p<0,001). Na resistência à flexão, a resina impressa V-Print Dentbase obteve valores significativamente inferiores (p<0,05), não tendo sido observadas diferenças significativas entre os restantes grupos.
Conclusão: As resinas CAD-CAM de impressão 3D apresentaram valores de microdureza inferiores às resinas convencionais termopolimerizáveis, antes e após o envelhecimento térmico. O envelhecimento térmico não teve influência nos valores de microdureza apenas na resina V-Print Dentbase. As resinas de impressão 3D obtiveram valores inferiores de resistência à flexão quando comparadas com as resinas termopolimerizáveis.
Objective: This in vitro study aimed to evaluate the microhardness and flexural strength of denture base resins, produced by the digital 3D printing method and submitted to thermal aging processes. Materials and Methods: A total of 32 rectangular specimens (4x10x3.3 mm) were manufactured, using two CAD-CAM resins (V-Print Dentbase and Denture 3D+) and two heat-conventional resins (Probase Hot and Villacryl H Rapid FN), n=8 for each group. All specimens were subjected to thermal aging by 1000 thermal cycles between 5ºC and 55ºC. The microhardness measurement was carried out with a Knoop tip before and after aging, as well as the measurement of flexural strength at 3 points. Results: Statistically significant differences were found in microhardness values measured before, after thermal aging, and in the flexural strength values between the studied resins (p < 0.001). The microhardness values were higher among groups of conventional resins before and after thermal aging. Regarding the flexural strength, the printed resin V-Print Dentbase obtained significantly lower values (p<0.05), with no significant differences being observed between the remaining groups. In the V-Print Dentbase printed resin group, when the two microhardness measurement times were compared, no statistically significant differences were observed (p=0.064). In the other groups, microhardness values were lower after thermal aging (p<0.001). Conclusion: The CAD-CAM resins presented microhardness and flexural strength values lower than conventional resins, before and after thermal aging. It was concluded that thermal aging had no influence on the microhardness values of the V-Print Dentbase resin.
Objective: This in vitro study aimed to evaluate the microhardness and flexural strength of denture base resins, produced by the digital 3D printing method and submitted to thermal aging processes. Materials and Methods: A total of 32 rectangular specimens (4x10x3.3 mm) were manufactured, using two CAD-CAM resins (V-Print Dentbase and Denture 3D+) and two heat-conventional resins (Probase Hot and Villacryl H Rapid FN), n=8 for each group. All specimens were subjected to thermal aging by 1000 thermal cycles between 5ºC and 55ºC. The microhardness measurement was carried out with a Knoop tip before and after aging, as well as the measurement of flexural strength at 3 points. Results: Statistically significant differences were found in microhardness values measured before, after thermal aging, and in the flexural strength values between the studied resins (p < 0.001). The microhardness values were higher among groups of conventional resins before and after thermal aging. Regarding the flexural strength, the printed resin V-Print Dentbase obtained significantly lower values (p<0.05), with no significant differences being observed between the remaining groups. In the V-Print Dentbase printed resin group, when the two microhardness measurement times were compared, no statistically significant differences were observed (p=0.064). In the other groups, microhardness values were lower after thermal aging (p<0.001). Conclusion: The CAD-CAM resins presented microhardness and flexural strength values lower than conventional resins, before and after thermal aging. It was concluded that thermal aging had no influence on the microhardness values of the V-Print Dentbase resin.
Descrição
Palavras-chave
Teses de mestrado - 2021 Saúde Oral