Timing of Deciduous Tooth Eruption in Children from Bojnurd, Iran: A Comparison with Global Reference Standards”

Background and purpose: Knowledge of the timing and correct sequence of primary tooth eruption is essential for dentists and pediatric dental specialists in developing appropriate treatment plans, determining optimal follow-up intervals, and scheduling periodic examinations. This ensures proper care and preservation of these teeth until their natural exfoliation. Therefore, the present study aims to compare the eruption age of primary teeth in children from Bojnurd, Iran, with global reference standards. Materials and methods: This cross-sectional study included 400 children aged 4 to 36 months, selected based on predefined inclusion criteria. The eruption age of primary teeth was assessed through clinical examination and recorded using a standardized checklist. Following the dental examination, additional information was collected, including birth height and weight, type of feeding (breast milk or formula), and maternal age during pregnancy. All collected data were entered into SPSS software (version 24) and subjected to statistical analysis. Results: In the present study, which aimed to investigate the factors influencing tooth eruption and to compare the average eruption age of primary teeth with global reference standards, no significant differences were observed in relation to birth height (P=0.45), maternal age during pregnancy (P= 0.54), or type of nutrition (breast milk vs. formula) (P = 0.35) between boys and girls. However, a statistically significant difference was found in birth weight, with boys having a higher average birth weight than girls (P= 0.001). The eruption age of the maxillary central incisors (P> 0.001), lateral incisors (P > 0.001), canines (P= 0.028), and first molars (P> 0.001), as well as the mandibular central incisors (P > 0.001), lateral incisors (P > 0.001), first molars (P > 0.001), and second molars (P = 0.003), was found to be significantly later than the global reference values. Additionally, type of nutrition showed a statistically significant effect only on the eruption timing of the central incisors in both the maxilla and mandible. Conclusion: In the present study, it was found that, overall, the eruption age of primary teeth in children from Bojnurd was significantly later than the global reference standards.