Age estimation studies play a great role in forensic science and for dental clinicians. The most frequently used method in predicting the age of children is Demirjian’s, based on dental panoramic radiographs and development curves for both genders. However, a problem exists when ethnic origin of a particular child is not available or ethnicity is unreliable. So, for age estimation, international dental development curves from different databases collected in several populations need to be created. This study collected a database of 9,577 dental panoramic radiographs from 8 different countries: Australia, Belgium, England, Finland, France, French-Canada, South Korea, and Sweden. The database consisted of 4,742 girls and 4,835 boys. Demirjian’s method was used to establish international dental development. Additionally, the 99th and the 99.99th percentiles to dental maturity curves were added for more reliability. The study was two-fold: (1) to give dental maturity standards when the ethnic origin is unknown and to compare the dental maturity of these different populations and (2) to compare the dental maturity of these different populations. In order to obtain the dental maturity score, a gender-weighted score was calculated for each stage of the seven teeth specific of multiethnic sample. A high efficiency was indicated for International Demirjian’s method at 99 percent CI making it useful for forensic purposes. The international method is less accurate than Demirjian’s method developed for a specific country, due to inter-ethnic variability. In conclusion, Australians were identified as having the fastest dental maturation and Koreans having the slowest. Figures, tables, and references