Bone mineralisation and growth is frequently used in legal and forensic medicine in the determination of an individual’s age. Correct evaluation of age is crucial for individuals, whose age is manifestly close to a legally important age threshold, such as the age of majority – the legal threshold for distinguishing between children and adults. This is especially important for individuals arriving from a different country, who may be seeking residence, but might not have a certified record of birth.  In these cases, dental data offer a relatively non-invasive means of age estimation, in which observations on the third molar are particularly useful, as this typically develops around 18y, the age of majority in many countries. However, challenges in accurate age estimation arise from between-individual variation, especially where ethnicities differ and with exposure to different socio-economic factors. To account for these differences, this international study is collecting a large body of dental data on individuals from across three continents with the aim of developing a robust age-evaluation model and improving the accuracy of current age-estimation tools.