Radiographic evaluation of secondary dentin formation in lower premolars for forensic age diagnosis of 18 years in a sample of south Indian adolescents and young adults.

There has been an increase in the need for alternate methods of dental age assessment, especially for the forensic age diagnosis of the 18th year of life. This is due to the completion of the third molar development before 18 years or the agenesis or therapeutic extractions of the third molars. The present study aimed to verify whether the secondary dentin formation in lower premolars can be used to determine the completion of the 18th year of life in a sample of South Indian adolescents and young adults. For this purpose, 800 orthopantomograms of 400 male and 400 female South Indian subjects aged 14- 22 were evaluated. The characteristics of the secondary dentin formation were determined in all mandibular premolars using the stage classification according to Olze et al (Int J Legal Med 126(4):615-21). The results showed that when stage 3 of secondary dentin formation was reached in the first premolars, the probability of the subject completing the 18th year of life was very high. However, only a few individuals in the studied population were at stage 3. Therefore, proceeding cautiously with this degenerative change in lower premolars is advised due to the higher inter-examiner differences. It is also recommended to use this method in conjunction with other age estimation methods. Further research should investigate other degenerative characteristics in the studied population.