Methods used on the mandibular third molar to estimate age on adolescent asylum seekers in Norway

Abstract

Globalization does not only lead to increased movement of goods, services and capital – an increasing number of people are also migrating either voluntarily or as refugees seeking asylum. Some arrive as unaccompanied minors, others claim to be minors, but the physical and mental appearances suggests otherwise. In Norway you are considered a minor if you are under 18 years of age, which will give you the rights and protection of a child, and the asylum application process will be expedited. For an unidentified foreigner to arrive in Norway age is crucial, and several methods have been developed to measure the alien’s correct chronological age.

The growth potential of teeth and tooth buds are less susceptible to malnutrition, radioactivity or other socioeconomic factors compared to the skeleton. This opens the opportunity to estimate age based on teeth with less standard deviation than other methods. Tooth buds start developing in utero and the mineralization continues until late teens - early 20s. By clinical and radiographic examinations of teeth and tooth buds, the age of children, adolescents and young adults can be estimated.

Age estimation is important both for the individual and the society, and different methods are used for this purpose, many of them based on radiographic interpretation of tooth development. In Norway, the methods used for age estimation is Demirjian et al. for children up to 14 years of age, Haavikko for individuals up to 20 years of age, and Liversidge for individuals between 14 and 20 years of age. After the closure of the 3rd molar apex, Kvaal et al’s. method is used. The latter method is not used in Denmark and Sweden, because it has shown to be very inaccurate. It has been argued that there is no ethnical variation in tooth mineralization, but in 2008, H.M. Liversidge found significant ethnical differences in human tooth mineralization.

Dental age estimation based on 3rd molar mineralization stages is considered to be inaccurate. Even though, for the 15- 25 years age group, it is worldwide found to be one of the most accurate methods of those available today.