Objective: This study aimed to assess the relation between the dental age of seven left mandibular teeth determined by the Demirjian's method and skeletal age determined by the Baccetti's method. Materials and methods: This cross-sectional study evaluated 600 patients aged between 8–16 years, who were selected from those presenting to Orthodontics Department of Hamadan dental school and private orthodontic offices. The patients had good-quality panoramic radiographs and lateral cephalograms taken within 2 months of each other. Skeletal age was determined according to the cervical vertebral maturation (CVM) on lateral cephalograms. The dental age of seven left mandibular teeth was determined using the Demirjian's method. Data were analysed by the Spearman's and Pearson's correlation coefficients via SPSS 16. Results: CVM had significant correlations with dental age (0.780) and chronological age (0.792). Accordingly, the strongest correlation was noted between CVM and the developmental stage of second molars in both males and females. In males, the highest correlation between dental age and chronological age was in CS5 stage (0.724) while, in females, the highest correlation between dental age and chronological age was in CS4 stage (0.651). Conclusion: Considering the correlation between skeletal age and dental calcification, dental age, especially the developmental stage of mandibular second molars, based on panoramic radiographs, can be served as a primary diagnostic tool for determining the skeletal maturity stage of patients. © 2019 CEO