The Effectiveness of Adding Rice Husk Nanosilica to the Flexural Strength of Opaque Porcelain Coatings on Metal Ceramic Dental Crowns

Abstract

Background. Failure of dentures that are unable to withstand flexural forces is often a major problem in the use of metal-ceramic crowns. The use of rice husk nano-silica powder has been extensively researched in dentistry because of its ability to improve mechanical properties. This study aims to determine the effectiveness of nano-silica particles from rice husks on the flexural strength of the opaque layer on Co-Cr metal-ceramic crowns.
 Methods. The type of research is experimental laboratories in vitro with posttest only control group design. The research samples were rectangular Co-Cr metal and porcelain plated on top of the metal center totaling 25 samples which were divided into 5 treatment groups. Flexural strength measurement with three-point bending at UTM. Data were analyzed by independent T-test and way ANOVA.
 Results. flexural strength of Co-Cr metal ceramic crown with the addition of 0.25% rice husk silica; 0.5%; 0.75%.1% in the opaque layer is 70.431±4.168; 84.093±2.852; 100,672±4,182 and 115,092±3,821, respectively.
 Conclusion. There is an increase in the flexural strength of metal ceramic crowns with the addition of 0.25% silica; 0.5%; 0.75%,1% on opaque coating.