A fully automated deep learning framework for age estimation in adults using periapical radiographs of canine teeth

Determining age from dental remains is vital in forensic investigations, aiding in victim identification and anthropological research. Our framework uses a two-step pipeline: tooth detection followed by age estimation, based on either canine tooth images alone or combined with sex information. The dataset included 2,587 radiographs from 1,004 patients (691 females, 313 males) aged 13.42-85.45 years. The YOLOv8-Nano model achieved exceptional performance in detecting canine teeth, with an F1 score of 0.994, a 98.94% detection success rate, and accurate numbering of all detected teeth. For age estimation, we implemented four convolutional neural network architectures: ResNet-18, DenseNet-121, EfficientNet-B0, and MobileNetV3. Each model was trained to estimate age based on one of the four individual canine teeth (13, 23, 33, and 43). The models achieved median absolute errors ranging from 3.55 to 5.18 years. Incorporating sex as an additional input feature did not improve performance. Moreover, no significant differences in predictive accuracy were observed among the individual teeth. In conclusion, the proposed framework demonstrates potential as a robust and practical tool for forensic age estimation across diverse forensic contexts.