Observations on dental prostheses and restorations subjected to high temperatures: experimental studies to aid identification processes.

In large scale disasters associated with fire the damage caused by heat can make medico-legal identification of human remains difficult. Teeth, restorations and prostheses, all of which are resistant to even quite high temperatures can be used as aids in the identification process. In this project the behaviour and morphology of teeth and dental prostheses exposed to a range of high temperatures was studied. Healthy teeth, dental restorations and prostheses were placed in a furnace and heated at a rate of 30 degrees C/min and the effects of the predetermined temperatures 200, 400, 600, 800, 1000 and 1100 degrees C were examined by stereomicroscopy and scanning electron microscopy (SEM). Our observations show that some prostheses and restorative materials resist higher temperatures than theoretically predictable and that even when a restoration is lost because of detachment or change of state its ante-mortem presence can be confirmed and detected by both stereomicroscopic examination and SEM of the residual cavity. We further conclude that a reasonably reliable estimation of the temperature of exposure can be made from an analysis of the teeth and restorative materials.