Species identification of teeth of human and non-human

Species identification is very important in forensic science case. However, the existing methods in forensic practice to identifying the species of bone and teeth are not objective, accurate or brief enough. We have reported the classification of bone species by Fourier transform infrared (FT-IR) and chemometric methods. Here we further use this method to realize the rapid detection of teeth species. 50 teeth samples from human and non-human (bovine, dog, rat, rabbit) were used in this study. Uncontrolled environment conditions were set to simulate real forensic casework. Teeth sample were prepared by grinding powder and pressed into KBr tablet, then the spectral data were collected. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used in the study. The internal and external validations of PLS-DA results were 97.1% and 93.3% accuracy, respectively. The results illustrate that FT-IR spectroscopy be used as a practical tool to identify species of unknown teeth.

Automated summary

Species identification is crucial in forensic science, but the current methods lack objectivity, accuracy, and conciseness. In this study, the Fourier transform infrared (FT-IR) and chemometric methods were used for the classification of bone species and further applied for the rapid detection of teeth species. The results demonstrate that FT-IR spectroscopy can serve as a practical tool for identifying unknown teeth species.