Effects of high temperature on dental restorative materials for forensic purposes

This study aimed to observe the effects of high temperature on different restorative dental materials by detecting changes in their microstructural and elemental composition. Disk shaped samples (10 mm diameter, 2 mm depth) were prepared from 8 dental materials (compomer, glass carbomer, ormocer, giomer, zinc reinforced glass ionomer (GI), silver-alloy reinforced GI, zirconia reinforced GI, and conventional GI). Scanning electron microscopy/Energy dispersive X-ray spectroscopy (SEM/EDS) was used to characterize sample surface structures and elemental composition. The same samples were also analyzed using X-ray fluorescence (XRF) to determine the trace element content. Each sample was placed in a porcelain furnace and exposed to 900 °C for 30 min. Observations of macroscopic changes in samples after exposure high temperature were recorded. The microstructural changes in sample surfaces after incineration were detected by SEM. The elemental compositions obtained before and after the incineration were compared after repeating the XRF and EDS analyses. Dental materials demonstrated specific macroscopic changes and microstructural deteriorations detected by SEM images after exposure to high temperature. While several changes occurred in the elemental content of materials in terms of amount, the original elemental composition was preserved. The ability to distinguish dental materials by elemental analyses has had an important impact on the identification process.