Multinational analysis and comparison of dental resin composites for forensic purposes

The identification of human remains often relies on dental data, which remain stable under extreme postmortem conditions. Dental resin composites, in particular, can retain their microstructural and elemental characteristics after thermal exposure or degradation, providing valuable adjunct information in forensic identification. This descriptive cross-sectional study presents the development of an ongoing multinational reference database of 50 dental resin composites collected from nine countries: Australia, Brazil, China, Germany, Italy, Japan, Korea, Luxembourg, and Switzerland. Each sample underwent morphological and elemental characterization using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDS). Microstructural and compositional variability was observed across brands and countries; the database documents these differences through magnified imagery (2000 ×, 5000 ×, and 10,000 ×) and corresponding elemental spectra. Although geographical inference has inherent limitations due to global migration, displacement, dental tourism, and the international distribution of dental materials, resin composite analysis can contribute meaningfully to postmortem dental profiling, particularly where certain materials remain market- or region-specific. The database is designed as a practical comparison atlas for forensic odontologists, promoting systematic sampling and analysis of composite restorations during dental autopsies of unidentified human remains to support identification and assist in the preliminary reconstruction of geographic treatment history. The database is continuously updated and is available to forensic odontologists upon request. This research underscores the need for continued expansion, validation, and integration of resin-composite comparison databases into forensic odontology workflows.