EFFECTIVENESS OF NANOPARTICLE-BASED ACIDULATED PHOSPHATE FLUORIDE (APF) GEL ON SURFACE MICROHARDNESS OF HUMAN ENAMEL: AN IN VITRO STUDY

Aim: To compare the effectiveness of nanoparticle-based acidulated phosphate fluoride (APF) gel and conventional APF gel on the surface microhardness of human enamel. Materials and methods: This study was performed on 30 sound human teeth extracted in a 2 month period for the purpose of orthodontic or periodontal reasons. The crown portion of each tooth was divided into 2 halves and treated for 4 min, using for the right half a nanoparticle-based APF gel and for the left half a conventional APF gel. The surface enamel microhardness was measured using the Vickers microhardness test at baseline, after 24 hr, and at 30 days. Results: On analysis, after 24 hr, in the nanoparticle-based APF gel group, the tooth samples showed a significant increase in surface microhardness compared to those treated with the conventional APF gel. After 30 days, the microhardness in both the groups was reduced compared to that found at 24 hr. Conclusion: After 24 hr of treatment, the incorporation of nanoparticles of sodium fluoride, the active component in the APF gel, resulted in a significant increase in the enamel surface microhardness of teeth samples compared to treatment with a conventional APF gel.