Chitosan-Modified Alumina–Zirconia–Carbonate Apatite Nanoparticles-Filled Dental Restorative Composite Materials: Characterization and Mechanical Properties

In the field of restorative dentistry, composite resin is quickly overtaking other materials in terms of usage. It resolves the issue of the toxic nature brought on by the amalgams’ mercury content. The mechanical properties of resin-based dental restorative composites can be enhanced with the addition of filler material. This study examines the effects of chitosan addition to dental composites with alumina, zirconia, and carbonate apatite nanoparticles on their characterization and hardness. The composite for direct restoration is prepared by mixing UDMA–TEGDMA–DMAEMA– HEMA as the matrix and alumina–zirconia–carbonate apatite as the filler in the presence of chitosan as a coupling agent. The weight ratio of filler to matrix used is 70:30. The effects of various concentrations of chitosan are varied at 2%, 4%, and 6%. Samples are prepared by a synthetizing process to obtain alumina–zirconia–carbonate apatite nanoparticles. The diffractogram from XRD shows the formation of t -ZrO 2 and dahllite. SEM images reveals that the particle sizes of each sample with chitosan at 2%, 4%, and 6% are of 87.5 nm, 112.5 nm, and 150 nm, respectively. The hardness values of each sample with the same chitosan concentration