Mechanical Properties of PMMA Denture Base Reinforced by Nitrile Rubber Particles with Al2O3/YSZ Fillers

The aim of this research study is to investigate the effect of filler loading of alumina/yttrium stabilizer zirconia (Al2O3/YSZ) filler with nitrile-butadiene rubber (NBR) particles filled PMMA denture base material on the mechanical properties. The PMMA matrix (control group) was prepared 0.5% benzoyl peroxide (BPO) with PMMA powder as initiator. Al2O3/YSZ ceramic powders by ratio 50/50 using 1,3,5,7 and 10 wt% as filler loading and then, mixed with10 wt% NBR particles, respectively, into PMMA matrix using the internal mixture as powder mixture (powder component). The liquid component consists of 90% of methyl methacrylate (MMA) and 10% ethylene glycol dimethacryate (EGDMA as the crosslinking agent). The mechanical properties of NBR/treated ceramic fillers in PMMA composites were tested using impact strength (IS) and fracture toughness (KIC). The morphology of fracture surface of specimens was characterized using field emission scanning electron microscopy (FESEM). The IS and KIC values increased to 10.25 KJ/m2 and 2.58 MPa.m1/2 by 5% of loading filler compared to control group 5.27 KJ/m2 and 1.6 MPa.m1/2, respectively. Statistically, shows that the IS and KIC for PMMA reinforced by NBR and Al2O3/YSZ is significantly improved (P < 0.05). Therefore, this reinforced PMMA denture base is suitable to be used as prosthodontics applications.