Advances in forensic age estimation

Abstract

The ability to assign accurate age estimates to human remains and living individuals is becoming an increasingly important element of forensic practice. In mass fatality events, where many people lose their lives and are often unable to be visually identified, being able to separate individuals based on their age as determined by skeletal and/or dental development is a vital part of the Disaster Victim Identification (DVI) operation. For example, in the tragic bushfire disaster which struck Victoria in February 2009, of the 164 victims who lost their lives and were subject to the DVI process, 25 were under the age of 20 years, and many of these were located in commingled circumstances [1, 2]. Due to the severity of the fires and the condition of many of the remains it was only possible to identify a number of these by assessment of their age using dental and skeletal development [3]. Forensic age estimation also plays an increasingly important role in the assessment of living individuals of unknown age who have entered a foreign jurisdiction without identification papers, or with suspect identification documents. It is necessary to be able to determine the age status of these individuals for a number of reasons, including school entry and year level age requirements, and also for assessment of legal adulthood or childhood. Determination of an unknown age individual’s status as either an adult or a child is vital in terms of how that person will be treated by the law in not only criminal prosecutions, but also in immigration hearings, licensing applications and, increasingly importantly, determination of refugee status. Age assessment of living individuals is conducted by using various medical imaging modalities, such as conventional X-ray and CT scanning, in order to capture images of the developing skeleton and the dentition. The anatomical sites most commonly imaged are the hand/wrist region for assessment of skeletal development, the dentition for assessment of dental age, and more recently the use of CT scanning to capture images of the developing clavicle and the dentition [4, 5]. This imaging necessarily involves the use of ionising radiation with concomitant exposure to various tissues. This exposure is not at a level sufficient to cause immediate harm, but does raise the total lifetime dose of radiation experienced by the individual concerned. There are medical ethical and legal considerations involved in conducting radiological procedures on living people, with no definite medical need, that are yet to be properly addressed. In Australia and New Zealand, forensic odontologists and anthropologists have been using various age estimation methods for many decades, the majority of these developed from population studies originating in the United States, Canada, and Europe [6–9]. These methods were developed from research conducted many decades ago and on populations which geographically, environmentally, and nutritionally do not accurately reflect current population demographics. For juveniles, that is, those individuals under the age of 15 years, these systems, especially those describing dental development, have proven to be quite adequate and have served the profession well. Recent research, however, would suggest that for dental ageing at least, these older methods may not be as accurate as was once thought for young individuals [10], and it is suspected that they may be substantially more inaccurate for individuals older than 15 years of age. R. B. Bassed (&) Department of Forensic Medicine, Victorian Institute of Forensic Medicine, Monash University, 57-83 Kavanagh St, Southbank, Melbourne, Australia e-mail: richardb@vifm.org