The development of a tool to predict temperature-exposure of incinerated teeth using colourimetric and hydroxyapatite crystal size data

This study presents a novel tool to predict temperature-exposure of incinerated pig teeth as a proxy for understanding impacts of fire on human teeth. Previous studies on the estimation of temperature-exposure of skeletal elements have been limited to that of heat-exposed bone. This predictive tool was developed using a multinomial regression model of colourimetric and hydroxyapatite crystal size variables using data obtained from unheated pig teeth and teeth incinerated at 300 °C, 600 °C, 800 °C and 1000 °C. An additional variable based on the observed appearance of the tooth was included in the tool. This enables the tooth to be classified as definitely burnt (600 °C–1000 °C) or uncertain (27 °C/300 °C). As a result, the model predicting the temperature-exposure of the incinerated teeth had an accuracy of 95%. This tool is a holistic, robust and reliable approach to estimate temperature of heat-exposed pig teeth, with high accuracy, and may act as a valuable proxy to estimate heat exposure for human teeth in forensic casework.