The best known and most commonly practiced section of forensic odontology is dental identification of unknown human remains. Dental identification typically involves comparing post-mortem (PM) radiographs of unknown human remains to ante-mortem (AM) dental x-rays of the presumed decedent. The identification process can include dental records, dental casts, photographs, and other AM records which may prove to be useful for comparison to the unknown person(s).
The identification of unknown human remains can be accomplished by way of several additional methods. A common but unreliable means is by visual identification of the remains. This is often done by a surviving spouse, family member or friend of the decedent. While this is perhaps the most common method of identification, it is unfortunately a non-scientific method that is fraught with errors. Grieving survivors may often be overwhelmed by the circumstances involving the death and their emotions may cloud the objectivity necessary to confirm the identity. Therefore, the authorities will also attempt to confirm the identity by using more reliable scientific methods.
Scientific methods include the use of DNA, fingerprint comparison and dental, anthropological or medical records to positively identify the unknown remains. Each of these scientific comparisons employ established methodologies that will support (or refute) the identification. In some instances the authorities will use several of these reliable methods in an attempt to prevent any misidentifications (Figure 1).
Why is the identification of unknown human remains so important? There are several reasons. A most important reason is for legal proceedings that involve the execution of wills and authorization for payment of life insurance policy benefits. If the decedent cannot be positively identified, a death certificate usually will not be issued, thus preventing the passing of assets and settling of life insurance claims, as well as the payment of estate and inheritance taxes. Many government agencies require confirmation of the identity of the unknown remains! If the death of the unknown decedent occurred as a result of criminal behavior, the identity of that person must be proven before prosecution can proceed against those who committed the crime.
Culturally, the most important reason the positive identification must be completed is for the survivors and loved ones. A positive identification is necessary in order for the survivors to begin the painful process of closure, knowing that their loved one has passed. In today’s psychological and sociological cultures, closure cannot come to the survivors without absolute proof of death for their loved one.
Dental identification is the most expeditious and least expensive scientific means of identification. Research has proven teeth to be the hardest substance in the human body. Teeth are also protected by the soft tissue of the cheeks, hard jaw bones and are insulated by the tongue. Additionally, it is legally and scientifically accepted that the teeth and their surrounding structures are unique to each individual. Therefore, the ability of the forensic odontologist to identify and compare the unique features of the oral and peri-oral structures of the unknown to the AM dental record provides a reliable and scientific means of identification (Figures 2a and 2b). This is especially true when non-viewable human remains are recovered. This does not imply other scientific methods are not also valuable, but they often take far more time and can involve significant costs.