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, salivaryproteins, and measurement angle on the quantification of early dentalerosion by the analysis of reflection intensities from enamel. Enamelfrom 184 caries-free human molars was used for in vitro erosion incitric acid (pH 3.6). Abrasion of the eroded enamel resulted in a6% to 14% increase in the specular reflection intensity comparedto only eroded enamel, and the reflection increase depended on theerosion degree. Nevertheless, monitoring of early erosion by reflectionanalysis was possible even in the abraded eroded teeth. The presenceof the salivary pellicle induced up to 22% higher reflection intensitiesdue 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 improvethe sensitivity of the analysis at late erosion stages. The applicabilityof the method for monitoring the remineralization of eroded enamelremained unclear in a demineralization/remineralization cycling modelof early dental erosion in vitro.