title: Variation in elemental composition of human teeth and its application for feasible species identification.
abstract: Identifying human remains is a primary task in forensic science. In this study, we propose a possible new technique, handheld X-ray fluorescence (HHXRF), for determining whether a suspected tooth is an authentic human tooth. A total of 444 teeth obtained from 111 human skulls (male=62, female=49) aged between 30-67 years (51.81±8.37 years) were used as subjects. The teeth were scanned by HHXRF to acquire their elemental profile. Differences in elemental composition were analyzed for different tooth positions (numbers 1-32), between crown and root, and between sexes (male and female); also, the proportion of elements in relation to different human ages was examined. Teeth from 20 different animal species, serving as non-human teeth samples, were used to distinguish between human and non-human teeth through a stepwise discriminant analysis. Our results revealed that different tooth positions, different regions (crown and root) of a tooth, and different sexes demonstrated disparities in the proportion of several elements. The accuracy rate of predicting sex based on the elemental profile of human teeth was 65.5%. Likewise, a dissimilar distribution of elements between human and non-human teeth was observed, leading to a high degree of correctness of 83.2% for distinguishing them. In conclusion, elemental analysis by HHXRF could serve as a promising candidate tool for identifying human teeth in forensic science, but is ineffective for sex determination.
authors.affiliation: Animal Bone and Joint Research Laboratory, Department of Veterinary Biosciences and Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand. Electronic address: korakot.n@cmu.ac.th.
authors.forename: Korakot
authors.initials: K
authors.lastname: Nganvongpanit
authors.affiliation: Animal Bone and Joint Research Laboratory, Department of Veterinary Biosciences and Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand; Department of Biology, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand. Electronic address: k_buddhachat@yahoo.com.
authors.forename: Kittisak
authors.initials: K
authors.lastname: Buddhachat
authors.affiliation: Animal Bone and Joint Research Laboratory, Department of Veterinary Biosciences and Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand. Electronic address: muy_v3@hotmail.com.
authors.forename: Promporn
authors.initials: P
authors.lastname: Piboon
authors.affiliation: Animal Bone and Joint Research Laboratory, Department of Veterinary Biosciences and Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50100, Thailand. Electronic address: kat_kung@hotmail.com.
authors.forename: Thippaporn
authors.initials: T
authors.lastname: Euppayo
authors.affiliation: Excellence Center in Osteology Research and Training Center, Chiang Mai University, Chiang Mai 50200, Thailand. Electronic address: pasuk034@gmail.com.
authors.forename: Pasuk
authors.initials: P
authors.lastname: Mahakkanukrauh
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000818:Animals; D016002:Discriminant Analysis; D004602:Elements; D005260:Female; D005553:Forensic Dentistry / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D013045:Species Specificity; D013052:Spectrometry, X-Ray Emission; D014070:Tooth / Q000737:chemistry*; D019228:Tooth Crown / Q000737:chemistry; D014092:Tooth Root / Q000737:chemistry
chemical_list: D004602:Elements
keywords: Animal; Classification; Element; Forensic; Human; Teeth