Assessing the impact of Ag: TiO₂ and Ag: ZrO₂ nanoparticles on the flexural strength of self-cured denture base resin

Abstract This study investigates the effect of silver, titanium dioxide, and silver, Zirconium dioxide nanoparticles on the flexural strength of self-cured denture base resin. The samples were divided into four groups according to the addition of different nanoparticles to the self-cured acrylic PMMA. Control group A, reinforcement group B (Ag + TiO 2 ), reinforcement group C (Ag + ZrO 2 ) and reinforcement group D (Ag + TiO 2 + ZrO 2 ). The samples were again divided into three subgroups according to the nanoparticulate addition ratio of 0.1, 0.3 and 0.5 wt.% TiO 2 and ZrO 2 each with a fixed ratio of 0.3wt.% Ag as antimicrobial. Excluding group D addition, it was 0.05, 0.15, 0.25 wt.% for both TiO 2 and ZrO 2 with 0.3 wt.% Ag. After immersing the samples in distilled water for 48h, the flexural strength was measured using the three-point bend test. Evaluation of flexural strength showed a significant decrease with an increasing percentage of nanoparticles, except the increase in the percentage of additions of ZrO 2 showed an increase in flexural strength. The samples underwent X-ray diffraction examination and FESEM to describe nanoparticles and examine the structure of acrylic samples. X-ray diffraction revealed the absence of mistake diffraction, indicating high crystal structure purity. In addition, images from the scanning electron microscope showed a homogeneous distribution of nanoparticles within the acrylic structure. Maximum flexural strength was seen in the 0.3 wt.% Ag-0.15 wt.% TiO 2 -15 wt.% ZrO 2 and minimum in 0.3 wt.% Ag -0.5 wt.% TiO 2 . The modified samples also exhibited colour changes. We conclude flexural strength value depends on the percentage of additions and type of nanoparticles.