Comparative analysis between size and mass ratio of nano-Al 2 O 3 in the performance of dental composite and finding the optimum composition

Abstract

Dental composites provide better bonding with tooth tissue as compared to other traditional materials such as amalgam. However, the development of dental composites relies on experimental results of physical, mechanical and thermal properties of the dental composite obtained after applying the strategy of filler technology, i.e., changing size, shape, surface modification and mass ratio of filler or reinforcement. In the present research, nano-Al₂O₃ particle size and filler mass ratio were varied to study their effect on the physical, mechanical and thermal behaviour of dental composite. The particle size was varied in the range of 30 nm, 50 nm and 70 nm. Nano-Al₂O₃ filler mass ratio was varied in the range of (0, 5, 10 and 15 wt. %). Fourier transform infrared analysis was done to check variations in absorption peak and band in the spectrum due to variation in the filler mass ratio and size. Physical properties, mechanical properties and thermal properties were investigated. It was observed that hardness, compressive strength, diametral tensile strength, flexural strength and stress intensity factor were increased by 133%, 13.6%, 27.4%, 25% and 20%, respectively, on adding 5 wt. % of nano-Al₂O₃ and decreased by 13.5%, 8.1%, 15.3%, 13.9% and 10.3%, respectively, on increasing particle size from 30 nm to 50 nm. The thermal degradation temperature was increased by 31.8% and 36% on adding 5 wt. % and increasing particle size from 30 nm to 50 nm, respectively. It can be concluded that in the case of nano-sized particulate filler, mass ratio played a more significant role than filler size in regards to optimization of physical, mechanical and thermal properties.