Soft tissue removal by maceration and feeding of Dermestes sp.: impact on morphological and biomolecular analyses of dental tissues in forensic medicine.

Maceration techniques remove soft tissue by the destruction of biomolecules, but the applied techniques may also affect the morphology and the molecular integrity of the hard tissue itself. The impact of seven different techniques for soft tissue removal on morphological and biomolecular parameters of teeth and dental tissues was systematically examined. All methods tested showed significant changes in dental morphology and in the molecular integrity of DNA and the dental proteins, as revealed by aspartic acid racemisation (AAR). In forensic casework this may have severe impacts on the results of morphological methods (e.g. age estimation based on root translucency) and of biomolecular analyses (e.g. age estimation based on AAR and DNA analysis). Therefore, age estimation based on AAR should not be applied to tissue treated in such a manner, and it is recommended that teeth for analysis should be extracted before soft tissue removal. DNA in the hard tissue seems to be less susceptible to soft tissue removal than proteins, and several of the tested maceration techniques appear not to have a damaging effect on DNA. Generally, the indication for soft tissue removal demands a careful case management to avoid methodological collisions.