What method is used to compare geographical regions based on dental composition?

The method utilized to compare geographical regions based on dental composition focuses on the comparison of strontium and its isotopes in teeth. This approach is grounded in the principle that different geographic areas have distinct geological compositions, which in turn affect the strontium isotopic ratios found in local food sources. When humans consume these food sources, the strontium and its isotopes incorporate into their dental tissues.

By analyzing the isotopic composition, forensic scientists can trace an individual's origins or movements across different regions, providing valuable insights in forensic investigations, especially in cases involving unidentified remains. This method allows for a more precise geographical analysis as strontium isotopes can reflect the local geology and environment, giving it an advantage over other methods that may not provide the same level of geographical specificity.