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GrinLine Identification Using Digital Imaging and Adobe Photoshop

NCJ Number
226562
Journal
Journal of Forensic Sciences Volume: 54 Issue: 2 Dated: March 2009 Pages: 422-427
Author(s)
Susan A. Bollinger D.D.S.; Paula C. Brumit D.D.S.; Bruce A. Schrader D.D.S.; David R. Senn D.D.S.
Date Published
March 2009
Length
6 pages
Annotation
This paper describes a method by which an antemortem photograph of a victim can be compared with a postmortem photograph in order to facilitate the identification process.
Abstract
The procedure developed is called the GrinLine Identification (GLID) technique. This technique compares grins seen in earlier (antemortem) photographs with photographs of postmortem anterior teeth made by or under the direction of a forensic odontologist. In the technique described, Adobe Photoshop is used to enhance, analyze, and compare photographs of grins. The mechanism required to create a postmortem grin is to draw back the lips and reveal the teeth in a smile, grimace, or snarl. Postmortem photographs should reproduce the perspective variations of an antemortem photograph. In order to achieve this, multiple photographs should be made using stepwise increments in horizontal and vertical angulations. Both maxillary and mandibular arches can be analyzed. The change of reaching a conclusion that helps to lead to identification is greatly increased when multiple individual characteristics are visible in the antemortem image. The ability to see all of at least one tooth is preferable for sizing a comparison image, but may be achieved with a single dimension. Forensic odontologists must maintain awareness of the possibility that any antemortem photograph may show an anterior dentition that has since been replaced with restoratives. Careful investigation of the time of placement of restorations is vital for a valid GLID comparison. The GLID technique works best in individual cases or in limited populations of unknowns. In the current study, 10 subjects between 27 and 55 years old provided earlier photos of themselves displaying broad smiles. These were compared with later photos using the GLID technique for matches. 15 figures and 4 references