All that glitters is not gold: X-ray fluorescence analysis of a fixed dental prosthesis from Colecção de Esqueletos Identificados Século XXI, Portugal (CEI/XXI)

Int J Legal Med. 2024 Mar;138(2):685-691. doi: 10.1007/s00414-023-03048-4. Epub 2023 Jun 22.

Abstract

Access to better health care anticipates that more medical devices can be found alongside skeletal remains. Those employed in oral rehabilitation, with available brands or batch/series, can prove useful in the identification process. A previous study in the Colecção de Esqueletos Identificados Século XXI described macroscopically the dental prostheses. An unusual case of a dental device with chromatic alterations demonstrated to require a more detailed analysis. The individual, a 53-year-old male, exhibited, at both arches, a fixed tooth-supported rehabilitation, with gold colouring classified initially as a gold-palladium alloy. Simultaneously, a green pigmentation deposit was observable in bone and prosthesis. This investigation aimed to verify the elemental composition of the dental prosthesis alloy. Elemental analysis was performed by X-ray fluorescence in two regions (labial surface of the prosthetic crown and the root surface of the lower right lateral incisor). Both the spectra and the qualitative results found higher levels of copper and aluminium, followed by nickel, iron, zinc, and manganese. No gold or palladium was detected. The most probable assumption is that a copper-aluminium alloy was used, as its elemental concentration corresponds to those measured in similar devices. Dental prostheses of copper-aluminium alloys have been made popular since the 1980s, particularly in the USA, Japan, and Eastern Europe. Apart from the biographical information, it was also known that the individual's place of birth was an Eastern European country, which highlighted the usefulness of this type of information when dealing with missing people cases.

Keywords: Dental prosthesis; Element analysis; Forensic anthropology; Human identification.

Publication types

  • Case Reports

MeSH terms

  • Aluminum / analysis
  • Copper / analysis
  • Dental Prosthesis*
  • Fluorescence
  • Gold Alloys / analysis
  • Humans
  • Incisor
  • Male
  • Middle Aged
  • Palladium* / analysis
  • Portugal
  • X-Rays

Substances

  • Palladium
  • Copper
  • Aluminum
  • Gold Alloys