Background: Primary dentition is a determinant for future permanent occlusion. Objective: This aimed to evaluate the prevalence of malocclusion and associated variables in the primary dentition among preschoolers in the city of Tbilisi, Georgia. Methods: A cross-sectional survey was conducted among kindergarten children aged 3–5 years. Orthodontic characteristics were assessed by one calibrated clinician (E.G). Questionnaires were given to parents to record associated variables like general health problems, functional changes, and the presence of non-nutritive sucking habits. Results: A total of 396 participants aged 3-5 were included in the study. The prevalence of malocclusion was 49.8%, without significant differences among genders. The prevalence of Class II malocclusion was 21.2%(±4.091), followed by a deep overbite, i.e, 10.7% (±3.14), crossbite, i.e, 7% (±2.561), anterior open bite, i.e, 6.9%, and Class III malocclusion, i.e, 1.6% (±1.513). A total of 41.5% of children with breathing problems had Class II and 13% had crossbite. Speech disorder in 46.8% of cases was associated with anterior open bite. Pacifier users had Class II in 22.5%, deep overbite in 12.2%, and open bite in 9.2% of cases. There was a high prevalence of anterior open bite (25.2%) in children with a thumb-sucking habit (RR=4.90). These data sets are statistically reliable (p < 0.05). Conclusion: Almost half of the evaluated preschoolers had malocclusion. The most frequent disorder was Class II. Malocclusion is associated with non-nutritive sucking habits and mouth breathing.

Background. Primary dentition takes the most important role in the development of permanent dentition. Primary second molars determine the eruption and position of permanent first molars. Early diagnosis and treatment could prevent the establishment of occlusal anomalies and deformities, therefore this study aimed to collect data about the prevalence of malocclusions based on the deciduous second molar terminal planes among the Tbilisi preschoolers. Methods. A total of 396 children aged 3-6 years, with an equal number of male and female subjects, were examined in kindergartens drawn from ten districts of Tbilisi, using the PPS (probability proportional to size) method. The relationship between distal surfaces of primary second molars was evaluated and recorded according to Baume’s classification. The significance level is 0.05 for all statistical tests. Results. Out of investigated preschoolers, 52.7% showed the flush terminal plane, followed by the distal step in 21.2% and mesial step in 26.1% of cases. There were no significant differences in genders. The most prevalent relationship between deciduous second molars was the flush terminal plane, with equal distribution in all age groups. The frequency of distal step decreased with age, more frequently recorded in the 3 to 4 year age group. The mesial step was mostly recorded in 3-4 and 5-6 year groups. Conclusion. The flush terminal plane is the most frequent molar relationship, followed by mesial and distal step. Prevalence of distal mesial step significantly decreased with age, while mesial step relationship showed the tendency to increase. The flush terminal plane showed little change with age.