Enamel Structural Changes induced by Hydrochloric and Phosphoric Acid Treatment

Abstract

Raman and IR spectroscopy showed that the treatment with both hydrochloric and phosphoric acids induced a decrease in the carbonate content of the enamel apatite. At the same time, both acids induced the formation of HPO42- ions. After H3PO4 treatment, the bands due to the organic component of enamel decreased in intensity, while they increased after HCl treatment. Replicas of H3PO4 treated enamel showed a strongly reduced permeability. Replicas of HCl 15% treated samples showed a maintained permeability. A decrease of the enamel organic component, as resulted after H3PO4 treatment, involves a decrease in enamel permeability, while the increase of the organic matter (achieved by HCl treatment) still maintains enamel permeability.The results suggested a correlation between organic matter and enamel permeability. Permeability was affected by etching technique and could be involved in marginal seal, gap and discoloration at the enamel interface, still causes of restoration failure.

Comparative clinical and psychosocial benefits of tooth bleaching: different light activation of a 38% peroxide gel in a preliminary case–control study

“…Even if inoffice bleaching involves the application of higher concentration of bleaching agents, and often also requires light activation of the whitening product, longer sessions are necessary to guarantee the effectiveness of the treatment, although this leads to an obvious increase in the costs of treatment [10]. Further, before bleaching, it is always recommended to examine the surface characteristics of dental enamel carefully, in order to avoid unwanted side effects such as, for instance, enamel structural changes or the progression of white-spot lesions [11][12][13].…”

Microhardness, Structure, and Morphology of Primary Enamel after Phosphoric Acid, Self-Etching Adhesive, and Er:YAG Laser Etching

“…The induced chemical alterations resulting from etching treatment are important for the evaluation and further improvement of adhesion systems [13]. In this study, the chemical composition of the enamel surface was measured by EDS.…”

“…ions [13]. Additionally, Torres-Rodríguez et al [14] reported that the degree or mineralization of bovine enamel removed by phosphoric acid remains constant, indicating that mineral and organic components are lost at the same rate.…”

Detection and monitoring of early dental caries and erosion using three-dimensional enhanced truncated-correlation photothermal coherence tomography imaging

“…Surface erosion in teeth is a result of direct exposure of a tooth to acid (such as drinking orange juice), which results in removal of material without bacterial origin. 25 eTC-PCT was applied to imaging this lesion type to further investigate its potential for dental erosion imaging. As opposed to demineralization caries, which at early stages presents itself as demineralization below a healthy surface enamel layer, erosion occurs as mass loss at the surface level with a secondary effect being the spread of demineralization in the layers immediately adjacent to the surface.…”