Abstract: Objective: To study the effect of bioactive glass on promoting dentin remineralization at different time points. Methods: 0.5mol/L EDTA was used to prepare completely demineralized dentin plates, which were randomly divided into 5 groups according to different treatment time points: experimental group A (1 day), group B (4 days), group C (7 days), group D (14 days), and blank control group E. The dentin morphology and the physicochemical properties of minerals were detected by focused ion beam scanning electron microscopy (FIB SEM), energy dispersive X-ray (EDX), X-ray diffractometer (XRD), and attenuated total reflection fourier transform infrared spectrometerATR-FTIR). Results: FIB SEM showed that the longer the treatment time was, the denser the minerals and the higher the degree of occlusion of dentin tubules were. EDX showed that the calcium-phosphorus content and the calcium-phosphorus ratio in group D were significantly higher than those in group A, B, and C (P<0.05). ATR-FTIR showed that the longer the treatment time was, the higher the absorption peak strength of phosphate was. And XRD showed that groups B, C, and D had formed diffraction peaks similar to hydroxyapatite. Conclusion: BAG can promote the completely demineralized dentin to form minerals similar to hydroxyapatite structure, which has accumulated effect as time proceeded.

Key words: bioactive glass, remineralization, time