Estimation of dental age using HPLC-technique to determine the degree of aspartic acid racemization.

Age determinations of adult individuals are of great importance within the forensic sciences. Presently, age changes in the teeth provide good means for this. The best method up to now has been "Gustafson's method" with modifications. Over the last 10 years a new chemical method, based on the racemization of aspartic acid in enamel and dentine, has been developed. Enamel and dentine belong to the very few tissues that do not have metabolic turn-over after formation. Both reliability and validity have been shown to be high, and this method therefore seems to be the best choice for the future. However, most studies to date have been using expensive and special instruments (gas chromatographs or amino acid analyzers) for these determinations. This study was performed to explore if the same determinations can be carried out with ordinary HPLC technique. It was shown that there is a good correlation between the ratio of D- and L-forms of the aspartic acid and age of the tooth. The correlation coefficient was 0.97, which is close to those presented with the other techniques, where r has been 0.95 - 0.99. The prediction of an individual age can be made with a 95% confidence interval of about +/- 12 years.