Impacto dos produtos clareadores de venda livre nas propriedades ópticas (alteração de cor e brilho) de dentes submetidos ao tratamento ortodôntico

Abstract

Teeth whitening has become one of the most requested dental procedures by the public, who are now looking for satisfactory and quick results on the market. As a result, many options have become commercially available such as over-the-counter (OTC) whitening products. These have gained popularity due to their reduced value and easy acquisition, but there are not enough studies to evaluate their efficiency and subsequent adverse effects. On the other hand, some patients during orthodontic treatment seek different whitening alternatives on the market, even relying on the influence of metal brackets during the whitening process. Therefore, this in vitro study evaluated the impact of over-the-counter products on the optical properties (changes in color and brightness) of teeth undergoing simulated orthodontic treatment. Thus, 80 bovine teeth were selected, cleaned with pumice stone and stained in instant coffee for 3 days, then washed with running water and dried. After this process, the initial color assessment was carried out by a trained blind evaluator using an X-Rite benchtop spectrophotometer. The gloss was obtained with the aid of a gloss measuring device (Glossmeter). 80 metal brackets were then cemented onto the crowns, aiming to simulate orthodontic treatment. The teeth were separated into five groups (n=16): Conventional in-office whitening with 35% hydrogen peroxide (HP) – positive control; Toothpaste with 2% HP; Mouthwash with 2.5% HP; Paint-on with 6% HP; Conventional dentifrice without HP – negative control. After the whitening protocols, the samples underwent a shear resistance test to remove the orthodontic metal brackets. The resin resulting from bracket bonding was removed using multi-bladed drills. In the statistical evaluation, a significant difference was identified between the groups for color change where ΔEab – p = 0,0000532 for all the groups, with ΔEab to the group HP35 = 11.09, MOUHP = 10.47, DSHP = 8.49, DHP = 7.75 e PON = 10.24; and ΔE00 – p = 0,000069 to all the groups where ΔE00 to the group HP35 = 16,38, MOUHP = 15,26, DSHP = 11,45, DHP = 11,17 e PON = 14). The statistical test did not detect a considerable difference in the increase in brightness found after bleaching between the experimental groups (p = 0.20). Therefore, the color change results of the over-the-counter whitening treatments evaluated, with the exception of toothpastes, were as satisfactory as those of in-office whitening, with no differences between the groups for brightness change.