STRENGTH AND FRACTURE TOUGHNESS OF WHISKER REINFORCED DENTAL RESIN-BASED COMPOSITES

Enhancing the properties of dental resin composites is of interest to researchers. The objective of the present investigation was to improve the strength and fracture toughness of dental composites via addition of silicon carbide whiskers and substitution of commonly used filler materials with stabilized zirconia ceramic powder. It was also intended to study the effect of powder- to- whisker ratio on mechanical properties of the resultant composites. The flexural strength and fracture toughness of composite samples with different whiskers loadings were measured. It was found that addition of whiskers to the composites enhances the mechanical properties of the composites. The strength and fracture toughness increased by increasing the amount of whiskers. The flexural strength of a composite having ۶۰wt% whisker and ۱۰wt% zirconia powder was about ۲۱۰ MPa while that of the composite having only ۶۰wt% ceramic powder was about ۱۱۰ MPa. The microstructural examinations revealed that reinforcing mechanism was whiskers pull-out as well as crack deflection.

کلیدواژه ها:

DENTAL ، RESIN ، COMPOSITE ، SILICON CARBIDE ، WHISKERS ، ZIRCONIA ، FLEXTURAL STRENGTH ، FRACTURE TOUGHNESS