Received 20.12.2022
DOI: 10.35556/idr-2023-2(103)12-15

Mechanical properties of tooth enamel and dentin after etching with citric acid with different concentrations using nanoindentation
Egina D.V., Maksyukov S.Yu., Nektarevskaya I.B.
Federal State Budgetary Educational Institution of Higher Education “Rostov State Medical University” of the Ministry of Healthcare of the Russian Federation
Russia, 344022, Rostov-na-Donu, Nakhichevanskiy Lane, 29

E-mail address: kafstom2.rostgmu@yandex.ru

Summary
In this paper, mechanical properties (Young’s modulus and indentation hardness) were measured for three samples of healthy human enamel and dentin using nanoindentation in order to compare their mechanical characteristics. Each sample was a longitudinal section obtained from one maxillary molar, which was subjected to 60-second exposure in citric acid with different concentrations (0.5 wt.%, 3 wt.%, 5 wt.%). The Nanotest 600 Platform 3 nanoindentometer was used to test the samples. Load-displacement curves for both enamel and dentin were obtained for each of the three sections. As a result of experiments, a number of characteristic curves of the dependence of the indentation depth on the applied force (load—displacement curves) were constructed for each of the three slices. The dependence of changes in the mechanical properties (reduced Young’s modulus, indentation hardness) of human tooth enamel on the concentration of citric acid applied to the tooth surface has been established: an increase in the concentration of citric acid leads to a decrease in Young’s modulus and indentation hardness. No such correlation was found for dentin in this study.

Keywords: tooth enamel, dentin, citric acid, mechanical properties, nanoindentation.

For citation: Egina D.V., Maksyukov S.Yu., Nektarevskaya I.B. Mechanical properties of tooth enamel and dentin after etching with citric acid with different concentrations using nanoindentation. Stomatology for All / Int. Dental Review. 2023, №2(103): 12-15. doi: 10.35556/idr-2023-2(103)12-15

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