Synthesis and Characterization of Hydroxyapatite/Silver Nanoparticles Composites and Their Antibacterial Properties for Dental Filling Application

The hydroxyapatite/silver nanoparticles (HA/AgNPs) composites were synthesized using a two-step physiochemical method. Firstly, a mixture of Ca(NO3)2·4H2O and K2HPO4 was combined at pH 9 and subjected to various microwave treatments (5, 10, and 15 min). Secondly, Ag was incorporated into the HA to produce HA/AgNPs. Through FT-IR study, the peaks at 945.12, 1014.52, 1346, and 1633.7 cm−1 correspond to the deformation of PO43− ions, stretching vibration of PO43− ions, stretching mode of CO32−, and the O–H functional group’s bending vibration, respectively. The scanning electron microscopic analysis revealed the presence of finely dispersed AgNPs within a size range of 30–90 nm, with an average particle size of approximately 40 ± 5 nm. The HA particles exhibited a size distribution ranging from 60 to 120 nm, with an average particle size of about 55 ± 5 nm. Furthermore, the HA/AgNPs nanocomposites antibacterial properties were evaluated against Gram negative bacterium, Escherichia coli, and Gram-positive bacterium, Staphylococcus aureus. HA/AgNPs exhibited remarkable antibacterial performance at a concentration of 100 g mL−1 and MIC values of about 6.25 and 12.5 g mL−1 against Escherichia coli and Staphylococcus aureus, respectively. A dental amalgam prepared by mixing mercury and HA/AgNPs. This biomaterial can potentially serve as a dental filling material.