The aim of this study was to look at the normal variability in third molar development in 18 years old, and to compare 2 scoring systems and 5 tables for dental age estimation. In addition to see how well they corresponded to each other and compare user friendliness. Two independent observers have collated and analyzed 269 panoramic radiographs with regard to the development of all third molars present, The variation in third molar development in 18 years old was found to vary from early root development stages, to complete root formation, with the main concentration around the later stages of root formation. Males developed third molars earlier than females, and the maxillary third molar develop earlier than the mandibular. The age estimation tables according to Mincer was found to have the highest prevalence of dental age at 18 years for both male and female, and is the most accurate system of the five systems studied. The scores according to Demirjian were considered the most user- friendly and easy-to-use system.