RESEARCH ARTICLE
Effect of Fluoride Gels on Microhardness and Surface Roughness of Bleached Enamel
Ana L.P China 1, Nayara M Souza 1, Yasmin do S. B. de L Gomes 1, Larissa D Alexandrino 1, Cecy M Silva 2, *
Article Information
Identifiers and Pagination:
Year: 2014Volume: 8
First Page: 188
Last Page: 193
Publisher ID: TODENTJ-8-188
DOI: 10.2174/1874210601408010188
Article History:
Received Date: 4/8/2014Revision Received Date: 5/9/2014
Acceptance Date: 9/9/2014
Electronic publication date: 14 /11/2014
Collection year: 2014

open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Abstract
The effect of bleaching treatments containing added calcium and combined with neutral or acidic fluoride gels on tooth enamel was investigated in vitro through Knoop microhardness (KHN) and surface roughness (SR) measurements. A total of 60 bovine incisors were tested, including 30 for SR measurements and 30 for KHN measurements. The specimens were divided into 12 groups and subjected to a bleaching agent with hydrogen peroxide 35% (Whiteness HP 35% Maxx, FGM) or hydrogen peroxide 35% with calcium (Whiteness HP 35% Blue Calcium, FGM) and a fluoride treatment flugel acidulated phosphate fluoride (APF) or flugel neutral fluoride (NF). Control specimens were submitted to bleaching treatments without fluoride. Microhardness tests were performed using a Knoop indentor. Roughness measurements were obtained using a roughness analyzer. Measurements were obtained before and after treatment. The specimens were stored in distilled water at 37 °C between treatments. The results were analyzed using descriptive and inferential statistics. Treatments using APF combined with 35% HP caused a decrease in microhardness, while NF combined with HP 35% Ca increased the enamel hardness. Fluoride gels did not alter the SR of the bleached enamel.