THE CHEMICAL COMPOSITION OF THE ENAMEL OF PERMANENT AND DECIDUOUS MOLAR TEETH AND ITS CONTRIBUTION TO THE ENAMEL MICROHARDNESS

Todorova A. V., Ulyanov V. O., Breus V. E.

DENTISTRY

Scentific article

Recently the increased number of data demonstrates the existence of two key factors that contribute to the enamel microhardness – its chemical composition and orientation of the enamel crystallites. However, the existing research are mostly focused on the chemical and mechanical properties of only permanent tooth enamel. The aim of the current research is to measure the content of Ca, P and F in the different zones of enamel of the permanent and deciduous molar teeth and to measure the mean microhardness values of the primary enamel in the different zones of the deciduous human molar teeth. Object and methods. 90 primary and 60 permanent human molar teeth with sound enamel were used for the research. The content of Ca, P and F was measured by the method of the comparative dispersion of double refraction. The mean microhardness values of the primary enamel were measured using the Vickers’ indentation technique. As a result of the conducted research the data regarding the distribution of the Ca, P and F within the primary and permanent enamel was obtained. Also the mean microhardness values were measured in the different zones of the crown of deciduous molar teeth. Conclusions 1. It was determined no statistically significant differences in the concentrations of Ca and P between the different zones of enamel of both permanent and deciduous molar teeth. 2. The superficial layers of both primary and permanent enamel exhibited significantly higher content of the fluoride ions that than the middle and deep layers. 3. The primary enamel exhibited lower concentrations of Ca and F ions and higher concentrations of P ions in comparison the permanent enamel. 4. The averages measures of the microhardness values were lower for the primary enamel than for the permanent enamel. 5. It was observed no statistical difference between the microhardness values in the different zones of the primary molar teeth’s crown.

dental enamel, chemical composition, microhardness

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«Bulletin of problems biology and medicine» Issue 2 (144), 2018 year, 372-376 pages, index UDK 611.018

10.29254/2077-4214-2018-2-144-372-376