NCJ Number
226564
Journal
Journal of Forensic Sciences Volume: 54 Issue: 2 Dated: March 2009 Pages: 433-438
Date Published
March 2009
Length
6 pages
Annotation
This study assessed the presence of the fluorescent properties of composite resin (used in restorations in dentition) exposed to increasing temperature, so as to determine the temperature range in which fluorescence was lost, and it identified any physical changes in composite resin as a function of increasing temperature.
Abstract
The study found that as the fluorescing molecules in composite resin are subjected to heat, the fluorescing property is lost. This occurs at a fairly low temperature, 300 degrees C, as shown by ultraviolet (UV) illumination. Although UV light is an excellent method for detecting composite resin in a deceased individual not subjected to fire, it may be necessary for examiners to discontinue the use of UV light for the inspection of the dentitions of victims subjected to fire. In these circumstances, the resin will not show a contrast from the tooth structure; investigators may then mistakenly conclude that a resin is not present. Traditional inspection with X-radiography and tactile sensation would be the best means of examining for composite resin under these circumstances, since the radiopacity of the resins will be maintained under heat. Radiopacity of the resin is determined by the addition of heavy elements in the inorganic filler particles. The composition of the inorganic filler particle is not affected by high temperatures. The study prepared 27 discs of resin and exposed them to increasing temperatures of 200 degree C-900 degrees C in 100-degree increments for 30 minutes. Analysis was performed with Fourier transform infrared spectroscopy, UV-visible light spectrophotometry, scanning electron microscopy/energy dispersive X-ray spectroscopy, optical microscopy, and UV illumination. Characterization of the material was recorded at each temperature range. 1 table, 5 figures, and 10 references