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Uniqueness of the Human Anterior Dentition: A Geometric Morphometric Analysis

NCJ Number
218488
Journal
Journal of Forensic Sciences Volume: 52 Issue: 3 Dated: May 2007 Pages: 671-677
Author(s)
Jules A. Kieser Ph.D.; Valeria Bernal Ph.D.; John N. Waddell; Shilpa Raju BDS
Date Published
May 2007
Length
7 pages
Annotation
Since one of the tenets underlying bitemark analysis for suspect identification is that the anterior teeth have distinctive characteristics, this study examined whether or not the anterior dentition of individuals was unique.
Abstract
The study findings show that the incisal surfaces of the anterior dentition are unique. Individuals differ not only by the relative position of their teeth, but also by their arch shape. When individuals with similar arcade shape were compared, differences in tooth orientation were still evident. In the current sample, which was selected to have lower levels of individuality in their anterior dentition than the general population, there were no two individuals with identical tooth arrangement and orientation. No attempt was made to determine whether each distinctive anterior dentition would be accurately transferred either to human skin in a bite or to wax for an accurate comparison to the skin bite. The study used geometric measurement techniques based on landmark and semilandmark data. Measurements were done on the incisor and canine occlusal surfaces of 50 randomly selected orthodontic cases of youth (17-20 years old) of both sexes. The measurements calculated Procrustes distances between tooth outlines. In order to analyze shape variation among individuals, researchers conducted principal components analyses on the partial warp scores. These were derived from Partial Procrustes coordinates aligned by means of thin-plate spline decomposition based on the bending energy matrix. 9 figures and 42 references