The inter relationships among growth parameters (weight, height) and ectopic eruption of permanent first molars of children aged 6-9 years in Kerman, Iran

BACKGROUND AND AIM: Ectopic eruption (EE) of the permanent first molars (PFMs) results from a discrepancy between the jaw growth rate and the growth rate of these teeth. The present study was undertaken to evaluate the prevalence of EE of PFMs in Kerman, Iran, and then determine the relationship between growth parameters (height and weight) and this developmental anomaly. METHODS: In the present study, 2025 children aged 6-9 years were examined to determine the prevalence of eruption of PFMs. Examinations were carried out with the use of tongue depressors under adequate light. Height and weight were determined in the control (without EE of PFM) and the case (with EE of PFM) groups, and then registered in the relevant checklist. Descriptive statistical methods were used for the analysis of qualitative data at a confidence interval (CI) of 95%. Chi-squared test was used for comparisons between the two groups in relation to age and gender. RESULTS: In the present study, prevalence of the EE of PFMs was 2.8% in 6 to 9-year-old children in Kerman. The rate of this developmental anomaly was higher in boys compared to girls and higher in the maxilla than in the mandible; however, the differences were not significant (P > 0.05). The prevalence of EE was higher in children with a lower mean age and a lower mean height and weight, which was significant statistically (P < 0.05). EE was more common unilaterally than bilaterally, but the difference was not significant (P > 0.05). In addition, there was no significant relationship between cleft palate or lip and EE (P > 0.05). CONCLUSION: Children in the lower than normal height and weight percentile are more susceptible to the EE developmental anomaly.