NCJ Number
188636
Journal
Japanese Journal of Legal Medicine Volume: 54 Issue: 2 Dated: August 2000 Pages: 207-218
Date Published
August 2000
Length
12 pages
Annotation
This article discusses the racemization method in the estimation of age from teeth based on the constant age-related increase in the amount of aspartic acid in dentin.
Abstract
The method for estimating age from teeth using the racemization of amino acids is referred to as the racemization method. This method is based on the characteristics of the constant age-related increase in the amount of D-aspartic acid in the dentin. Age was estimated by measuring the ratio of D-aspartic acid to L-aspartic acid. Bucco-lingual longitudinal sections were prepared at the central part of each tooth and than samples of powdered whole dentin were prepared. The powder was mixed and used to measure the D/L ratio in the dentin. In order to accurately estimate age from forensic specimens, the D/L ratios were simultaneously measured in more than four control teeth of the same type from subjects of known age. Control teeth were necessary because it was sometimes difficult to maintain constant running for gas chromatography to obtain reproducible values in different runs. Therefore, for every measurement, an equation was determined for calculating age from the D/L ratios of control teeth and estimated the age of the specimen tooth by substituting in its D/L ratio. The most reliable results were obtained using samples of lower incisors or pre-molars that were single-rooted teeth with a small volume of dentin. The sampling of dentin was easier than from other teeth. The results from the cases examined, using the racemization method, was a 3-year deviation from the actual age. These results showed that racemization of amino acids can be used for accurate estimation of age from teeth. Tables and graphs