Analytical Survey of Restorative Resins by SEM/EDS and XRF: Databases for Forensic Purposes

• NCJ Number: 222355
• Journal: Forensic Sciences Volume: 53 Issue: 2 Dated: March 2008 Pages: 419-425
• Author(s): Mary A. Bush D.D.S; Raymond G. Miller D.D.S; Ann L. Norrlander D.D.S; Peter J. Bush B.S.
• Date Published: March 2008
• Length: 7 pages
• Sponsoring Agency: American Soc of Forensic Odontology (ASFO)
• Publication Format: Article
• Publication Type: Report (Study/Research); Program/Project Description
• Language: English
• Country: United States of America

Annotation

This article describes the development and testing of two databases for dental resins, which are intended for use in forensic dental analysis, primarily in the identification of deceased victims based on a matching of postmortem and antemortem dental work.

Abstract

In developing the databases, 32 modern resins available in the United States were collected. All were restorative resins, including composites. Each resin was analyzed using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS). An EDS spectrum was collected at 500x magnification, with a collection time of 300 seconds. Since the spectrum was to be used as a reference, a long collection time was required in order to obtain the best signal to noise ratio. The spectra were than converted to the industry standard format of the Electron Microscopy Society of America. The EDS spectra were uploaded to the SLICE (Spectral Library Identification and Classification Explorer) software. Uploaded data for each resin include manufacturer, lot number, expiration date, and trace element concentration. The backscattered electron images for each resin (500x, 1000x, and 5000x) were also included. The same resins were analyzed by X-ray fluorescence (XRF), in order to create a custom spectral reference library. The resin disks were analyzed in a laboratory test stand, and reference spectra were generated. A sample of bone and tooth was also added to the library. The resins were also analyzed with XRF in order to determine the trace elemental concentrations. The trace analysis revealed additional elements not displayed with EDS. The results of these analyses were recorded for addition to the SLICE database, providing an additional discriminator between resin brands. Both the SLICE resin EDS database and the XRF custom spectral library were tested by analyzing a number of unknown samples of resin. 2 tables, 4 figures, and 7 references