Influence and Effects of CaF2 and Al2O3 Addition to Bioactive Glass in the SiO2–Na2O–CaO–P2O5 System Pertaining to Dental Applications

The present work deals with synthesizing melt-derived Fluoride and Alumina-modified S53P4-based bioactive glasses with anti-bacterial attributes and evaluates their properties for dental applications. CaF2 was introduced, substituting CaO (10, 9, and 8 wt%), as fluoride promotes tooth remineralization, restricts its demineralization, and effectively suppresses bacterial activity. Al2O3 was added, replacing CaO (1, 2, and 3 wt%), to enhance the mechanical properties of the glass. The structural characteristics of the synthesized glasses were studied using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Raman Spectroscopy. The dissolution characteristics and Bioactivity of the synthesized glasses were examined by measuring changes in pH, Fluoride ion (F−) concentration, and weight loss and by subjecting the samples to FTIR and Raman Spectroscopy after immersion in Simulated Body Fluid (SBF) as well as in Artificial Saliva (AS) over 28 days. Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) were used to investigate the microstructure and elemental composition of the glass samples before and after immersion in SBF. The antibacterial properties of the prepared glass samples were tested in vitro against Escherichia coli. The inhibition of bacterial growth was measured using the standard agar-plate count technique. The analysis revealed evidence of bactericidal action, which increased with Fluoride content. The produced glasses exhibited strong bioactivity, as evidenced by the formation of Hydroxyapatite and Fluorapatite on their surfaces, following immersion in SBF and AS at 37 °C, demonstrated by the FTIR, Raman Spectroscopy, and SEM results. The Bioactivity of the glasses was found to decrease with an increase in Al2O3 content. The pH and the F− concentration were observed to escalate higher in the Artificial Saliva than in the SBF. The addition of Al2O3 and CaF2 significantly elevated the brilliance and fluidity of the glass at the melting temperature, respectively.