Optimizing dental composites with nano limestone and tricalcium particulate fillers: A study on physical and mechanical properties

This study investigates the enhancement of dental composites using nano limestone and tricalcium phosphate fillers. Five composite formulations (TLC0-TLC4) were developed using organic polymers (Bis-GMA, TEGDMA, DMAEMA, CQ) and inorganic fillers. The methodology involved fabricating these composites and evaluating their physical and mechanical properties, including density, water absorption, solubility, polymerization shrinkage, hardness, compressive strength, and surface roughness. Results showed that density and voids increased with filler content, with TLC4 achieving the highest density at 1.39 ± 0.16 g/cm³. Water absorption and solubility increased, while polymerization shrinkage decreased to 0.66 ± 0.05% in TLC4. TLC4 demonstrated the highest hardness (72.8 ± 2.4 H.R.V.), compressive strength (248.41 ± 3.11 MPa), and surface roughness (0.62 ± 0.25 µm). Thermal analysis revealed significant weight loss and decomposition, while Fourier-transform infrared spectroscopy analysis provided detailed chemical composition insights. Wear resistance was evaluated through pin-on-disc tests and signal-to-noise ratio analysis, with FE-SEM confirming TLC4's superior performance. VIKOR analysis using the ENTROPY method ranked TLC4 as the most effective composite. This study offers valuable data for selecting and optimizing restorative dental materials.