Dynamics of the demineralization of temporary teeth using ultrasonic shadow velosymmetry and autofluorescence microscopy <i>in vitro</i>

Abstract

BACKGROUND: Given the high prevalence of caries in preschool children, additional methods for diagnosing hidden carious foci with deep structural demineralization of the hard tissues of temporary teeth without generating X-rays must be updated. AIM: To improve methods for studying the demineralization of hard tissues of primary teeth using ultrasonic shadow velosymmetry and autofluorescence microscopy. MATERIALS AND METHODS: The study included primary second molars (n=11). Samples of primary teeth were placed in a test tube with a demineralizing solution on days 1, 4, 8, 21, and 31. The samples were examined by autofluorescence microscopy and ultrasonic shadow velosymmetry according to the exposure time. The rate of acid demineralization of the primary teeth samples was assessed using our score scale. The averages were compared using the Wilcoxon W-test (p 0.05). Pearson correlation analysis was used, taking into account the statistical significance of the correlation coefficients for p 0.05. RESULTS: Analysis of samples of hard tissues of primary teeth by ultrasonic shadow velosymmetry showed that the velocity of the ultrasonic wave passage decreases with increasing exposure to the demineralizing solution and acquires a linear character with a negative regression coefficient. The decrease in the ultrasonic wave velocity in the enamel and dentin of the samples directly correlated with the degree of demineralization. CONCLUSION: The conducted experiment on the hard tissues of primary teeth showed that demineralization not only leads to micromorphological structural changes in the hard tissues of enamel and dentin but also affects the physical and acoustic properties of the samples.