Authors: Charlier Philippe
We present here the complete methodology of the microscopic analysis of dental calculus deposits (DCD), a calcified residue frequently found on the surface of teeth, for both forensic and anthropological/osteo-archeological purposes. Its sampling and analysis seem straightforward and relatively reproducible. Samples studied by direct optical microscope (OM) or scanning electron microscopy (SEM) provide many cytological, histological, and elemental analyses observations, i.e. precious data for the identification of these remains, the reconstitution of their alimentation and occupational habits, and propositions for manner of death.
We describe here the complete protocol of dental calculus deposits (DCD) examination for forensic or osteo-archaeological/anthropological purposes, using classical optical microscope (OM) and scanning electronic microscope (SEM), in order to identify any tissue or, at least, cellular fragments still present in this substance that could be helpful for the determination of the individual habits (with a pur- pose of identification) and/or pathologies (with a purpose of determination of a manner of death). It consisted in a direct application of microscopic examination coupled with an elemental surface analysis.
Sampling: for each individual, two 3–5-mm-long fragments of DCD are sampled directly from the teeth (lingual position of mandibular premolar or molar) with sterile or decontaminated surgical instruments, and deposed in sterile box without any conservative agent.
Samples are then cleaned by a fine scraping with non-contami- nating plastic instruments and a delicate vaporization of pressured air on all the faces during 10 min. No gold covering is realized in order to be able to perform elemental analysis on the surface.
Environmental Scanning Electron Microscope (SEM) examination of each sample is directly performed on a Philips XL30 CP with X-ray micro- analysis (energy-dispersive X-ray spectroscopy). The resolution of the microscope is 3.5 nm at 30 kV using the secondary electron detector. All images are stored using a standard resolution digital frame store.
A study with optical microscope is also carried out on other samples of DCD. The methodology employed for the sampling and preparation of DCD was:
The microscopic (optical and SEM) examination of dental calculus deposits (DCD). Potential interest in forensic anthropology of a bio-archaeological method. Philippe Charlier, Isabelle Huynh-Charlier, Olivia Munoz, Michel Billard, Luc Brun, and Geoffroy Lorin de la Grandmaison. Legal Medicine 12 (4) 163 - 171 doi:10.1016/j.legalmed.2010.03.003
Charlier Philippe, Department of Forensic Medicine and Pathology, University Hospital R. Poincaré (AP-HP, UVSQ), Garches, France
Correspondence to: Charlier Philippe ([email protected])
Source: Protocol Exchange (2013) doi:10.1038/protex.2013.043. Originally published online 15 April 2013.