Validity of laser induced breakdown spectroscopy (LIBS) in determining age and sex from tooth specimens

To determine age and sex from tooth specimens using Laser-Induced Breakdown Spectroscopy (LIBS).

A total of 170 human teeth samples between age of 15-86 years of both male and female sex were obtained for the study based on the inclusion and exclusion criteria. All the tooth samples were mounted and ground sections of about 1.5-2 mm thickness were prepared. Each tooth sample was subjected to LIBS along the cemento-enamel junction and spectrographs were acquired that denoted the elemental presence in each tooth sample.

The elemental concentration of Ca I, Ca II, P and Fe in all the teeth samples declined as the age progressed. The Peak intensity of Ca, P and Fe was observed in the second decade of life. The overall concentration of Fe exhibited highest intensity in both male and female samples when compared with other elements assessed. The general concentration of all the elements were relatively higher in the female samples when compared to those in males.

The CEJ seems to be a better site for elemental analysis of tooth since multiple tooth sites are represented in this region and the other sites of teeth such as enamel or roots of teeth may tend to get fractured, and my not be available for the analysis. The signal intensities of trace elements seen to reduce with increase in age. However, certain external factors also seemed to have an influence on these outcomes.