Characterization of Enamel and Dentine about a White Spot Lesion: Mechanical Properties, Mineral Density, Microstructure and Molecular Composition

Abstract

The study focuses on in vitro tracing of some fundamental changes that emerge in teeth at the initial stage of caries development using multiple approaches. The research was conducted on a mostly sound maxillary molar tooth but with a clearly visible natural proximal white spot lesion (WSL). Values of mineral density, reduced Young’s modulus, indentation hardness and creep as well as the molecular composition and surface microstructure of the WSL and bordering dentine area were studied. The results obtained were compared to those of sound enamel and dentine on the same tooth. A decrease of mechanical properties and mineral density both for the WSL and bordering dentine was detected in comparison to the sound counterparts, as well as increase of creep for the enamel WSL. Differences in molecular composition and surface microstructure (including the indenter impressions) were found and described. WSL induces a serious change in the state of not only the visually affected enamel but also surrounding visually intact enamel and dentine in its vicinity. The results provide the basis for future studies of efficacy of minimal invasive treatments of caries.

Comparative Investigations of AlCrN Coatings Formed by Cathodic Arc Evaporation under Different Nitrogen Pressure or Arc Current

“…In the case of thin coatings, the most frequently used methods of measuring their hardness and modulus of elasticity are the nano-and micro-indentation methods. It should also be remembered that the penetration depth should be selected so that the substrate properties do not affect the results of the coating hardness measurement [ 41 , 42 , 43 ].…”

Tissue Dental Status and Features of Periodontal Microcirculation in Patients with New COVID-19 Coronavirus Infection.

“…In patients with a severe course, the leading symptom at the beginning of the disease is respiratory failure, which can then progress to multiple organ failure. In prognostic terms, one of the most unfavorable signs is the development of coagulopathies [22][23][24][25][26][27][28]. Against the background of viral infection, an immune complex "antigen-antibody" is formed, which leads to damage to the capillary endothelium.…”

Anti‐arthritic effect of chicken embryo tissue hydrolyzate against adjuvant arthritis in rats (X‐ray microtomographic and histopathological analysis)

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