VARIABILITY IN THE TIMING OF ERUPTION OF PERMANENT TEETH IN CHILDREN AND ADOLESCENTS LIVING IN THE UDMURT REPUBLIC

AIM of the study was to evaluate the influence of regional climatic living conditions of Udmurt children and adolescents of different sexes on the timing and rate of permanent tooth eruption using the example of upper and lower canines.

MATERIALS AND METHODS. The object of the study was children aged the first and second childhood periods, and adolescents of different sexes living in various mesoclimatic zones of the Udmurt Republic (UR). The total number of examined persons was 1,350. The interval between studies for each representative was 12 months. The data were presented in absolute numbers and as a percentage of the number of examined individuals for each year of the study, and the growth rates and increases in the number of individuals with erupted canines for each subsequent year from the moment of detection were calculated separately for the female and male populations. Statistical analysis of the data obtained was carried out using standard Excel statistical software packages (Statistica 10), The arithmetic mean (M), the standard deviation (σ), and the error of the mean (m) were calculated. To assess the significance of the correlation between the numerical values of populations of children living in different mesoclimatic zones, the correlation coefficient (r) was used and its error (S_r) was calculated.

RESULTS AND DISCUSSION. It was revealed that in favorable living conditions (southern regions of the UR), there is a tendency to outrun the teething process; synchronicity of the teething process; a similar duration of the teething process in time compared with unfavorable (northern UR) conditions. The final rate of increase in the population of children with erupted upper and lower canines in the southern regions significantly exceeded that in the north of the republic for both the female and male populations.

CONCLUSION. Awareness of the process of eruption, due to climatic living conditions, will help reduce the frequency of canine retention, providing early detection and preventive treatment. The presented data can be used as standards in assessing the eruption of permanent teeth for places with specific climatic living conditions.

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