Introduction: In modern medicine, one of the most accurate methods for detecting variability in the characteristics of twins is the use of genetic research and the study of the interaction of genetic factors on the dental development of the twins.
Aim: To evaluate and compare the oral hygiene status in the studied and treated four twin pairs on 8 to 10 years.
Materials and Methods: The study monitored the oral hygiene status of 4 twin pairs from 8 to 10 years of age (one male and 3 female pairs). To determine the level of oral hygiene, a Greene-Vermillion Oral Hygiene Index (OHI-S) was used. The presence of plaque after staining on the corresponding surfaces of the representative teeth was recorded. The Silness and Loe index determined the thickness and amount of plaque biofilm in the gingival third zone of the crowns of the examined teeth. The study was conducted at the Faculty of Dental Medicine - Varna, during the 2017/2018 academic year. Informed consent was obtained from each parent. The selection of children was random. The study was conducted by doctors, specialist in pediatric dentistry. The results were processed using the statistical program SPSS v. 20.0, using variation, dispersion and comparative analyzes.
Results: The results of the oral-hygienic status analysis showed that the twins studied had satisfactory oral hygiene according to the two indices. In terms of age, we noticed that twins under the age of 10 (8 and 9 years) had poorer oral hygiene than those at 10 years of age (p<0.05). According to OHI Green-Vermillion, the index was equal to 1.53 ± 0.34 for twins over 10 years, and 1.93 ± 0.27 for those under 10 years of age. The PLI Silness-Löe index was 1.81 ± 0.53 for children under 10, and 1.34 ± 0.21 for those over 10 years.
Conclusion: There was a significant difference in oral hygiene indices between 8 and 9 years of age, indicating that there was a difference in hygiene habits as they had the same genetic background.
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