Evaluation of Remineralization of White Spot Lesions with Quercetin Nanoparticles:an in vitro Study

Background: This study explored the synthesis of quercetin nanoparticles (QNPs) and evaluated the remineralization effect of QNPs on artificial white spot lesions on extracted human teeth. Material and Methods: QNPs were successfully synthesized, and their size was measured. Seventy-six extracted human molars were divided into 4 groups of n=19 to undergo a 10-day pH cycling protocol: 1000 ppm fluoride solution as aqueous NaF (group 1), 6.5% w/v quercetin microparticle solution (group 2), 4000 ppm QNP (group 3) and deionized water (group 4). Vickers microhardness tester, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) and atomic force microscopy (AFM) were used to measure the surface microhardness (SMH), Ca:P ratio and surface roughness (Ra), respectively. Results: After remineralization, the SMH values were significantly different among all the experimental groups (p<0.001). The fluoride and QNP groups had significantly greater SMH values than the quercetin group. The AFM data showed a significant decrease, but the differences were not significant. The Ca:P values were significantly greater than those of the control in all 3 experimental groups, but the QNP and fluoride concentrations were significantly greater than those of quercetin. There were no significant differences between QNPs and fluoride according to any test. Conclusions: It can be concluded from the results of this study that QNPs have similar remineralization potential to f luoride and are more effective than quercetin.