Anticaries potential of nanohydroxyapatite toothpastes

Quinn Skarich

Research Mentor: Livia Tenuta
Mentor Department: Cariology, Restorative Sciences and Endodontics, Dentistry
Author(s): Quinn Skarich, Rajani Bhat, Livia Tenuta
Session: Session 6 (3:00 PM – 3:50 PM)
Presentation Type: Poster 31

Abstract

Fluoride is the most important anticaries agent, but the search for fluoride-free alternatives to control caries has intensified in recent years. Hydroxyapatite (and its nano version, nHAp) has been suggested as a “tooth-like” material that could be effective for caries control. In this in vitro, blind and randomized study, we will test the anticaries potential of hydroxyapatite toothpastes, when compared to an established fluoride toothpaste. Enamel slabs will be obtained from bovine teeth; half will be used sound, and half will be demineralized in vitro to simulate an early caries lesion. Their surface hardness (SH) will be determined and they will be randomly assigned to 4 different treatment groups: 1) negative control (deionized water; no hydroxyapatite or fluoride); 2) positive control, fluoride toothpaste, 1,100 ppm F (from NaF) (Crest); 3) experimental toothpaste 1- Dr. Jen’s hydroxyapatite toothpaste, 10% nano-hydroxyapatite (nHAp); and 4) experimental toothpaste 2- David’s hydroxyapatite toothpaste, up to 10% nHAp. To evaluate the treatments’ ability to remineralize enamel, demineralized slabs (n=12) will go through the treatments 3 times a day in a pH cycling model to simulate remineralizing conditions. After 8 days, SH readings will be taken once again, and the %SH recovery will be calculated. To evaluate the treatments’ ability to inhibit enamel demineralization, sound slabs (n=12) will go through the treatments 2 times a day in a pH cycling model to simulate demineralizing conditions. The %SH loss will be determined. Statistical analysis will be performed using ANOVA and Tukey to compare the efficacy of the nHAp toothpastes against the positive and negative controls. Currently, we have 58 polished enamel slabs with an average SH of 334.7 kg/mm² and with a standard deviation of 12.1.