Changes in the enamel surface in patients with polymorphism of the <i>VDR</i> gene under the action of remineralizing composition and vitamin D

Abstract

BACKGROUND: The leading role in the pathogenetic mechanism of caries development is the imbalance between the de and remineralization of hard tooth tissues. The combination of VDR alleles affects calcium-phosphate metabolism. In 65% of the human population, the structure of the VDR gene has a genetic polymorphism. AIM: To study the effect of vitamin D and a remineralizing paste on the enamel surface structure in patients with genetic polymorphism of VDR gene receptors. MATERIALS AND METHODS: In 18 individuals with a polymorphism index of the VDR A/A gene, a laboratory indicator of 25 (OH) vitamin D in the blood of 18.20±1.84 ng/ml, according to orthodontic indications, the retinated third molars in the lower jaw were removed. Then, the samples were lowered into three flasks of six pieces with 100 ml of artificial saliva. Containers with teeth were divided into groups: group 1, with a solution of artificial saliva only; group 2, an additional 1,000 IU of an aqueous solution of vitamin D; and group 3, tooth enamel was treated for 2 minutes with an electric toothbrush with a paste containing a remineralizing composition, immersed in artificial saliva with cholecalciferol 1,000 IU. The flasks were in the thermostat at a temperature of 37.4 C per day. In all samples, electron microscopy of the enamel contact surface at the level of the crown equator was performed using a Tescan Mira 3 LMU microscope (TESCAN, Czech Republic) with an Oxford X-MAX 5 energy dispersive X-ray detector (Oxford Instruments, United Kingdom) with analysis of local mineral composition. RESULTS: In group 1, with electron microscopy of enamel, areas of increased mineralization alternated with areas of reduced density. The coefficient of the molar ratio Ca/P was 1.32±0.13, indicating the destruction of hydroxyapatites. In group 2 the intercrystalline pore space was filled with calcium and phosphate ions. In group 3, the enamel surface acquired a smooth homogeneous relief. An increase in the weight percentage of trace elements was observed, and the Ca/P ratio was 2.20±0.02, which indicated a phase of remineralization. CONCLUSION: Patients with VDR gene polymorphism have a vitamin D deficiency in the blood serum. The trace element composition of the enamel surface is characterized by a phase of demineralization. Treatment with remineralizing paste and addition of cholecalciferol solution to artificial saliva changes the structure of hydroxyapatite and increases the caries-resistant properties of enamel.