# Scanning electron microscope analysis of elements in amalgam restorations to determine when a deceased person may have lived. A method based on data from Scandinavia

## TL;DR

This paper explores using scanning electron microscopes to analyze dental amalgam restorations in human remains to estimate when a deceased person may have lived.

## Contribution

The study introduces a novel method using SEM–EDS to differentiate between types of dental amalgam for forensic dating.

## Key findings

- SEM–EDS successfully distinguished between copper amalgam and conventional silver amalgam.
- Copper amalgams had very low or non-detectable silver and tin levels.
- The method could help narrow down the time period of a deceased person's life.

## Abstract

When unidentified human remains are found, the aim must be to establish the identity of the individual. Being able to assess the time period when the deceased person has lived, might narrow down the search among missing persons. Dental amalgam alloys contain different elemental metals, and various alloy types have over time been introduced and abandoned at certain times, especially in Scandinavian countries. This study aimed to explore if a scanning electron microscope (SEM–EDS) can be used to determine the chemical composition of different dental amalgam restorations, with the focus to distinguish between copper amalgam and conventional silver amalgam. Six previously commonly used amalgams were selected, and five test samples were prepared from each of them. Each test sample was analysed with SEM–EDS at five separate sites, giving 25 readings for each amalgam brand. The SEM–EDS analyses identified noticeable differences in the composition of conventional silver amalgams compared to copper amalgams. The latter contained very low- or non-detectable amounts of silver and tin. The results showed that SEM–EDS could be a valuable accessory for identifying an unknown human remain.