Dental Anthropology and Forensic Dentistry

Dental Anthropology and Forensic Dentistry

Eric C. Chen

Do you ever idle around and channel flip until catching a split-second of CSI or NCIS, only to realize one hour later that you’ve watched the entire episode? Have you ever wondered how the ‘science’ actually works in real life in comparison to what happens in all those addicting, romanticized crime dramas? More importantly, have you ever seen a dentist solve any of these murder mysteries?

If you answered ‘yes’ or ‘no’ to any of the aforementioned questions, please continue reading.

But seriously, although television has yet to see a bright, young – and attractive – UCLA dentist solve an incredibly complex case on NCIS: Los Angeles, the field of forensic dentistry has long been a driving force in the handling of dental evidences to assist and solve innumerable cases around the world.

Before we begin, let’s consider some interesting and relatively unknown pieces in dental anthropology that relate to forensic dentistry.

For starters, considerable metric variation in dental anatomy has been documented across various worldwide populations. Sources of variation range from the genetic such as sex-based and population-level factors all the way to the environment such as stress and diet factors. The usage of modern technology in the form of calipers and computed tomography have enhanced our understanding of dental anthropology. Furthermore, the abundance and preservation of teeth as historical records further attest to the reliability of dental records.

Sexual dimorphism, for instance, is greatest dentally in human canine crowns. Differences also exist in dental tissue proportions with females having relatively more enamel than males, and males having relatively more dentine than females.

In addition, as shown from a 2005 study where researchers at the Department of Anatomy and Biological Anthropology at Japan’s Saga Medical School examined dental variation across 72 human populations, differences in mesiodistal and buccolingual crown diameters as well as odontometric shape factors exist across worldwide populations.

If we further consider non-metric variation of dental traits such as shovel-shaped incisors and the cusp of Carabelli, even more can be determined from a given dentition. Shovel-shaped incisors, where the maxillary central incisors physically resemble miniature shovels due to prominent lingual marginal ridges, are found more often in people of Native American and Asian descent; the cusp of Carabelli, a small additional cusp on the mesiolingual cusp of maxillary first molars, is found more often in people of European and African descent. These traits represent just a fraction of myriad dental traits recognized in dental anthropology.

Now to the fun stuff. How does dental anthropology translate into forensic dentistry?

It turns out you can reconstruct criminal events, identify remains, and even examine bite marks, just to name a few things that forensic dentists do. The application of the science of dental anthropology to the legal process centers around the identification of remains to assist in detecting a crime, and even the identification of dental records to determine the sex, age, ancestry, and even stature of an alleged perpetrator or victim.

For example, forensic dentistry has helped convict serial killers and rapists in many prominent criminal cases through substantial bite-mark evidence where the perpetrator was known to bite their victim.

Outside the justice system, forensic dentistry has done even more. After the 2011 Tohuku earthquake and resultant tsunami that devastated Japan, hundreds of dentists voluntarily rallied to match dental records with unidentified bodies. By checking the type of treatment and dental work done on the teeth of the bodies and using biometric identification techniques, dentists were able to help countless families come to terms with and properly bury their lost loved ones.

Without a doubt, dental anthropology and forensic dentistry can be used in a multitude of fascinating and beneficial ways to aid us not only in our understanding of the human condition, but also in the triumph of justice and the rebuilding of our weathered communities.

Although largely unknown to the general public and unlikely to be revealed on a crime scene show like CSI or NCIS any time soon, it is the unspoken, meticulous work of thousands and thousands of dentists around the world who remind us of the humility and significance in which we must serve in our esteemed yet humbled profession.