Volume 34, Issue 6 (November 1989)
Dental Characteristics of a Large Military Population Useful for Identification
The number and complexity of dental restorations has decreased for younger Americans. Since the presence and extent of restorations are important data for forensic science identification purposes, the Computer-Assisted Postmortem Identification (CAPMI) system was used to assess the practical effect of the decreased selectivity expected as a result of improved dental health.
Dental examination data from 7030 soliders were recorded on optical mark read forms and entered into a database. The data were reorganized and analyzed to generate summary statistics about the incidence of each type of restoration (divided into 16 categories) for both anterior, posterior, upper, lower, and combined segments. Patients' ages ranged from 17 to 49 with a mean of 24 years 5 months. Sixty percent were from 18 to 25 years old. A characteristic is defined as any situation other than a virgin tooth; for example, extracted, missing, unerupted, or restored. The average subject had 7 dental characteristics with approximately 75% having 4 or more. Within the entire population, 9% had 32 unrestored teeth. 3.6% had only one characteristic.
To test the selectivity and uniqueness of various combinations of dental characteristics, 363 simulations using the CAPMI system were made against the entire 7030 subject database. Sample records (33 per group) with 2, 3, 4, 5, 6, 7, 8, 9–11, 12–14, 15–18, and 19+ characteristics were chosen at random from the database and searches were made.
The variety of dental restorations was such that even the more common restorative situations yielded only two to four first-place ties. Eighty-five percent of all comparisons made with two or more characteristics gave a unique correct answer. Thirteen percent of the remainder were tied with three or fewer other records. It was concluded that although dental restorations are diminishing in frequency in the younger population they still provide a high degree of selectivity for forensic science purposes.