Effects of enamel abrasion, salivary pellicle, and measurement angle on the optical assessment of dental erosion

Abstract

Abstract. The present study assessed the effects of abrasion, salivary proteins, and measurement angle on the quantification of early dental erosion by the analysis of reflection intensities from enamel. Enamel from 184 caries-free human molars was used for in vitro erosion in citric acid (pH 3.6). Abrasion of the eroded enamel resulted in a 6% to 14% increase in the specular reflection intensity compared to only eroded enamel, and the reflection increase depended on the erosion degree. Nevertheless, monitoring of early erosion by reflection analysis was possible even in the abraded eroded teeth. The presence of the salivary pellicle induced up to 22% higher reflection intensities due to the smoothing of the eroded enamel by the adhered proteins. However, this measurement artifact could be significantly minimized (p < 0.05) by removing the pellicle layer with 3% NaOCl solution. Change of the measurement angles from 45 to 60 deg did not improve the sensitivity of the analysis at late erosion stages. The applicability of the method for monitoring the remineralization of eroded enamel remained unclear in a demineralization/remineralization cycling model of early dental erosion in vitro.

Optical pen-size reflectometer for monitoring of early dental erosion in native and polished enamels

“…Linear decrease and increase of the backscattered light intensity during demineralization and remineralization processes were reported by Kishen et al 18 Change of the specular and diffuse reflection intensities during erosion progression was investigated in our previous in vitro studies. 19,20 Particularly, sharp decay of the specular reflection was observed already in the early stages of enamel erosion in vitro, while the less pronounced increase of the diffuse reflection intensity was measured, which correlated well with the results of Thomas et al 17 Further investigation revealed a strong correlation between the decrease of the specular reflection and continuous surface roughening. 19 Significant change of the specular reflection was detected even in eroded and abraded surfaces.…”

“…19,20 This study presents a next step toward the To make this step, a handy and simple instrument was required based on the same optical system utilized previously. 19 Thus, the entire optics was miniaturized into a pen-size instrument, though the angles of incidence and reflection had to be reduced to 23 deg (versus 45 deg in the original prototype setup 19 ) to provide so small instrument head size that it could access all positions inside the oral cavity (Fig.…”

“…For example, salivary pellicle can be cleaned from the enamel, which minimizes its effect on the reflection signal significantly. 20 Abrasion 20 or other mechanical impacts are factors which affect the enamel roughness and should be standardized/controlled during the application of the instrument.…”

“…19,20 Briefly, teeth crowns were separated from the roots using Isomet ® Low Speed Saw (Buehler, Düsseldorf, Germany). The buccal sites of the specimens were embedded into the resin (Paladur, Heraeus Kulzer GmbH, Hanau, Germany) in two planar parallel molds.…”

Efeito da ordem de utilização de dentifrícios e enxaguatórios bucais contendo fluoretos e estanho na prevenção do desgaste erosivo

“…16,24 Na sequência, caso o desafio ácido persista, tem-se início o segundo estágio, no qual, devido à continua difusão dos íons hidrogênio para o interior do esmalte, ocorre uma desmineralização numa camada inferior, próxima a superfície, aprofundando a camada amolecida. 27,48 Assim, a magnitude do desafio ácido se torna maior que a capacidade de troca de minerais entre o dente e fluidos da cavidade oral, resultando, portanto, num desequilíbrio do processo de des/remineralização. Dessa forma, o esmalte vai sendo perdido, camada por camada, progressivamente, até o aparecimento do desgaste erosivo clínico.…”