Assessment of the changes in the petrous portion of temporal bone (pars petrosa ossis temporalis) under the influence of high temperature during the cremation process

Abstract

The petrous parts of temporal bones are considered to be the densest parts of the human skeleton. Because of their high biomechanical strength, these elements can be preserved well even exposed to destructive processes. It has been proved that these bones are very well preserved in cremation graves and thus can be used as the foundation for anthropological analyses of cremated remains. The aim of the study was to determine the degree of shrinkage of the petrous portion of temporal bone under the influence of high temperature during the cremation. In a modern crematorium in Prague (Czech Republic), an experiment was conducted by burning 15 human temporal bones and a fresh pig's heads with soft tissues. Nine measurements were collected from each bone before the burning process. Cremation was carried out under controlled conditions in a modern cremation oven—the process took 45 min, and the temperature reached 1000°C. All the bones were burned together to maintain the same experimental conditions. Measurements of the individual bones were then repeated, and the significance of the dimensional changes was assessed. The presented study pointed out the significant size's reduction at level to 14% for dry petrous parts of temporal bones, while the size of fresh bones changed to 28% of their mass depending on the examined feature. Furthermore, the results of comparative analyses revealed that the differences between burning of dry and fresh bones are insignificant.