[Laboratory examination of the desensitizers. Part 1: scanning electron microscope study]

The aim of the study. Improve the quality of dentine hypersensitivity treatment by modifying systems that seal dentine tubules (DT) with metal nanoparticles and their compounds.

The study included 18 extracted teeth. The preparations «Gluftored» (GF) and «Dentin-Versiegelungsliquid» (DVL) were examined. For their modification, sol of TiO₂ nanoparticles in distilled water and sol of Ti and TiC nanoparticles in ethyl alcohol were used. The particles had a size from 0.5 to 3 nm. In subgroups "A", the tooth was first wetted with hydrosol, and then immersed in alcohol; in subgroups "B", alcohol was added to the suspension of calcium hydroxide too. The results were evaluated using scanning electron microscopy. For each square millimeter we determined: the total number of DT and sealed DT, as well as the number of sealed DT with filling and fitting defects. When, the absolute and relative number of fully and qualitatively sealed DT were calculated. The differences between the groups were determined using the Kruskal-Walli's test.

The largest percentage (80.98%) of completely sealed DT was observed in the experimental group, where both the dentine surface and the calcium hydroxide suspension in the GF were modified with hydrosol and alcohol. This index was 1.86 times higher (p<0.001) compared with the original GF, and 1.17 times higher (p=0.352) compared with the DVL preparation.