Eruption time of the first Primary Tooth and its Relationship with Growth Parameters in Children

Abstract

Introdouction: Tooth eruption is recognized as an important aspect of human growth and development. It can be influenced by a number of factors, and it may reflect the general development of a child's body. The purpose of this study was to determine the age at which the first primary tooth erupted and its relationship with height, weight and head circumference in 3-15-month children in the city of Rasht,Iran. Materials and methods: This descriptive, cross-sectional study was conducted on 648 children (288 girls and 360 boys) aged between 3-15 months, which were randomly selected from all health care centers in Rasht (the children visit these centers regularly for vaccinations). Height, weight, and head circumference were measured on the same day. From the obtained data, descriptive statistical indices were calculated for the eruption time of the primary central incisors. Cox regression analysis was used to determine the relationship between tooth eruption and the three growth parameters. Results: The timing of the eruption of the first primary tooth ranged from 5 to 14 months. The first erupted tooth was the mandibular central inci-sor, with the mean age of eruption of 9.93 ± 0.11 months in girls and 10.13 ± 0.1 months in boys. There was a significant association between the eruption time of the first primary tooth and weight-forage in both girls and boys. The relationships of first primary tooth eruption with head circumference-forage and height-forage were significant only in boys. Conclusion: The first primary tooth erupted earlier in girls than in boys, and primary tooth eruption was significantly related to the measured growth parameters , i.e., height, weight, and head circumference .-16-First primary tooth eruption: relationship with growth parameters Materials and Methods In this descriptive, cross-sectional study, 648 children aged 3-15 months were selected according to cluster random sampling from seven health centers in Rasht. This age range was selected because children of this age group are easily accessible in health centers, which they visit for vaccinations. Only healthy, normal subjects were included in the study sample. To gather data, observations were made and interview techniques were used to complete questionnaires. The eruption time of the first primary tooth was the main variable, whereas the age, gender, height, weight, and head circumference of the child, as well as their use of iron supplements , were measured as underlying variables. Examination of the children was performed in conditions with sufficient light using disposable tongue blades and gloves. Observation of a tooth in the oral cavity signified that a tooth had erupted. Height, weight, and head circumference were measured on the same day that the children were examined. Nurses used standardized techniques and equipment to weigh children and measure their height and head circumference. (7) Each child was weighed with minimal clothing. Children were weighed either lying down or sitting on a leveled pan scale. Body length was measured from head to heels (to the nearest mm) using an infantome-ter. The growth parameters were selected according to WHO standards and the centers for disease control 2000 reference charts. (16) Statistical analysis was performed in SPSS version 10. Kaplan-Meier and survival analyses, as well as descriptive statistics, were used to determine the mean eruption time of the first erupted tooth. Backward conditional Cox regression was used to determine the relationship between the underlying factors and eruption of primary teeth. Of the 648 children examined in this study, 288 (44.5%) were female and 360 (55.5%) were male. The first erupted tooth in children was the mandibular primary central incisor, The mean age of eruption obtained from the present study in girls was 9.93 ± 0.11 months and in boys was 10.13 ± 0.1 months. lThe age range of eruption