Age-related legal problems are especially common in underdeveloped parts of Turkey. In terms of civil and criminal law, the ages from 13 years to 18 years are critical in our country. Estimation of age is a very significant in aspect of accordance with laws. The aims of this study were to evaluate the applicability and accuracy of the Demirjian technique for assessing southern Turkish children; to analyze the sexual dimorphism of dental age in the studied groups; and to define the relationship between the dental age and the degree of mineralization in mandibular permanent tooth in southern Turkish children. This study was performed using panoramic radiographs from 932 healthy southern Turkish children, 444 girls and 488 boys aged between 4 and 18 years. Statistical evaluations were performed using SPSS (Statistical Package for Social Sciences) for Windows 13.0 software. The mean difference between dental and chronological age was calculated for each age and sex group. The paired t-test was used to compare all data. The chi-square test was used for between-group comparisons of categorical variables. Continuous variables were tested for normality using the Kolmogorov-Smirnov test. Relationships between continuous variables were examined using Pearson's correlation coefficient. The same observer re-examined 700 teeth three months after the first examination. The results were evaluated with the intraclass correlation test and both measurements were statistically significantly similar with each other(R = 0.982, p = 0.0001). .Dental age (DA) and chronological age (CA) were consistent for boys in the 16-16.9 age group and for girls in the 9-9.9 and 15-15.9 age groups. From this study, we can conclude that dental age varies across ethnic populations. Additionally, dental maturation varies across different regions of the same country. Because Demirjian's standards are not suitable for all age groups of southern Turkish children, a new table is necessary for evaluating this population. Future studies using multi-ethnic population data are needed to establish the international applicability of Demirjian's method.