Histo-morphologic and gravimetric changes of teeth exposed to high temperatures – an in vitro study

Abstract

BACKGROUND

Fire intelligence is the multidisciplinary basis of reconnaissance, which includes determining the origin, cause, and identification of fire victims. Fire is a destructive force capable of inflicting significant damage. Destruction of soft tissue in fire disasters makes victim identification nearly impossible. Teeth are hard and tough and withstand such conditions. Analyzing the precise morphological, stereomicroscopic, histological, and gravimetric findings can extract valuable information from dental evidence in forensic investigations.

MATERIALS AND METHODS

 About thirty-six mandibular premolar teeth extracted for therapeutic purposes were exposed to high-temperature gradients. Macroscopic, stereomicroscopic, histological, and dry weight analyses were performed at each temperature gradient.

RESULTS

The color of teeth changed from yellowish orange to metallic black bronze to chalky white. Stereo microscopy showed intact teeth at 100°C, gradual microcracks at 500°C, and a fully fractured crown at 900°C. Decalcified sections revealed dilatation of dentinal tubular pattern at 300°C. Dentin tubules showed appearance of vapor bubbles at 400 °C, resulting in loss of typical architecture. In the ground sections, alterations in scalloping nature of dentino-enamel junction, coalescing radicular dentinal tubules, and sand cracking appearance of teeth were noted at 100°C, 300°C, and 900°C, respectively. Significant reductions in the weight of the teeth samples were observed with higher temperatures.

CONCLUSION

From the morphological, histological, and gravimetric changes on a tooth caused by fire, it might be possible to determine the temperature and duration of fire exposure, and the cause of the fire.