HARDNESS AND FRICTIONAL BEHAVIOUR OF DENTAL HYBRID COMPOSITE RESIN FILLED BY SILICON CARBIDE NANOFIBERS

The objectives of the present investigation is to determine the effect of light curing time on the hardness and friction coefficient of composite resin filled with (SiC NFs). The materials used are hybrid composite resin and SiC NFs. Four groups of composite resin specimens are prepared; one as received and three groups reinforced by SiC NFs in concentrations of 0.1, 0.2 and 0.3 wt. %. SiC NFs are manually mixed with hybrid composites resin. The resulting paste is packed into plastic bars. The specimens are then cured from both sides for 40, 60 and 99 seconds using a visible light curing unit. Surface hardness is measured using Shore D durometer test. The coefficient of friction is determined using two-body abrasion test. It was found that high curing times gave higher hardness values and moderate friction coefficient compared to low curing times. The minimum content of SiC NFs (0.1 wt. %) improved the hardness and frictional behavior. Based on that, it may be concluded that hardness and friction coefficient are significantly affected by curing times and SiC NFs concentrations.