Forensic Odontology is the application of the science of dentistry in a criminal investigation.  The use of odontology in forensics is as significant as that of fingerprints; for the identification of individuals. This branch is also being known by the term “Forensic Dentistry” as it entails the knowledge and skills of dentistry in cases of recognition of the person in a mass disaster, natural calamities, massacre; sexual offenses, and child abuse.

Here we will explore how teeth act as an aid in forensic investigation to identify individuals.

Earlier Use of Teeth as Aid in Forensic Individualization 

The very first use of teeth for identification has been recorded during the ADs century.

In India, forensic dentistry gained recognition during the era of Jai Chand; a great Indian monarch, Raja of Kannauj, who was murdered by Muhammad’s army in the year 1193.

Later, his dead body was recovered and recognition was done by his artificial teeth. Thereafter, the science of dentistry has become a promising aid in forensic individualization. 

Teeth Are The Hardest One!

The dentition is the most pliant structure in the human body, which allows identifications to be made even in cases of high decomposition. The teeth are sheltered by the soft tissues of the lips, tongue, and facial musculature consequently can endure very high temperatures, environmental factors, and extensive trauma. 

Human dentition consists of four types of teeth incisors, canines, premolars and molars showing variations in morphology like shape and size, colour, position, rotation, missing, wear & tear, and dental anomalies. This variation in the teeth structure and morphology comprises certain individual characteristics responsible in imparting inimitable identity to the persons.     

Forensic odontology involves the appropriate collection, preservation of dental evidence either in the form of post mortem or antemortem dental records or the evidence recovered from the crime scene, followed by their systematic analysis and examination.

Significance of Dentistry in Forensics 

Identification of Unidentified Person

In many cases, like arson and severe decomposition, fingerprint retrieval becomes difficult or sometimes impossible.

Also, when bodies are charred, decomposed, skeletonized, mutilated, or comingled, investigators require the services of a forensic anthropologist and forensic odontologist.

During an investigation, it can indicate or confirm identification, or assist in trauma assessment. 

In cases of mass disasters, such as floods, earthquakes, tsunamis, plane crashes, or terrorist attacks such as 9/11, dental evidence may prove vital to identify the dead, giving them back their names, family, and much-needed closure.

However, for the said purpose to be fulfilled, Antemortem dental records are required to be accessible for comparison to make the dental individualization rapid, precise, and reliable. 

Apart from the identification of unknown, forensic odontologists also contribute at multiple levels to assist in criminal investigations:

Identification of Unknown Remains

Tooth enamel is the hardest material produced by the body and hence teeth remain intact even after a massacre or rigorous putrefaction. Identification is based on the comparison of class and individual tooth characteristics of the unrecognized remains collected from the scene with the antemortem dental records available which include notes, radiographs, and casts; as well as artificial dental work, including fixtures and fillings. 

Identification of Fire-damaged Remains

During extensive fire exposure, the front teeth are the first to be lost. Even without teeth, the study based on any dentures and x-rays of jaws and skull can prove to be a reliable source of information for identification purposes. Moreover, identification can be established in severely damaged remains by matching antemortem root canals and fillings.

Victim Age at the Time of Death

Age estimation is an important aspect when it comes to identification. We can calculate the age of a victim in three ways – morphological, radiological, and biochemical methods.

Most of the morphology-based methods are feasible for individuals above 18 years.

A few examples of the morphological methods of age estimation include Gustafson’s method, Johanson and Maple, etc.

Growth of the third-molar, also known as ‘wisdom tooth’, is a reliable indicator for an adolescent or an early adult to establish whether the individual has reached the age of 18.

These methods of age estimation are considered relevant for establishing a legal majority in issues involving immigration. Legally, individuals under the age of 18 are handled differently. 

Radiological methods are readily used as these are non-destructive in nature. Other methods involving secondary dentine, length and width of pulp and root, are found to be useful for estimation of the age of individuals under the age of 18.

However, as age advances teeth undergo many external and internal wear and tears that lead to discrepancies between estimated age and chronological age.

Bite Mark Assessment

Bite marks are frequently encountered in cases of aggravated assault and abuse, such as sexual offenses, child abuse, human trafficking, etc. Forensic dentists assess and evaluate the marks on a victim by comparing them with the bite pattern of the suspected assailant. 

The very basic procedure of analysis employed by most forensic odontologists is as follows:

• Bite marks are photographed with a scale.
• Bite marks on the skin are taken over repeated intervals.
• Casts of impression are taken.
• Impressions are traced onto transparencies.
• Casts of suspect teeth are taken.
• Comparison between suspect cast and bite marks is done

The very famous case of the serial offender of the US, Ted Bundy, was brought to justice with the help of Bite marks. Plaster impressions of bite marks found on the victim’s body were compared with the known impression of Ted’s teeth which happen to be matched and got him convicted.

Race Determination

Humans can be categorized majorly into three races – Negroids, Mongoloids and Caucasoids.

There are some dental characteristics confined to the particular race which contribute to the identification process.

For instance, the incisors of people of Asian or native descent are shovel-shaped with ridges on the rear surface of the tooth than those of white or black descent which have blade form incisors with a flat profile.

Also, a few other characteristics such as the cusps of Carabelli and multicusped premolars can also assist in race estimation.

Conclusion

The forensic odontologist fulfils a very significant professional obligation by performing identification of human remains, bite-mark analysis of victims and suspects in child and adult abuse cases, and on alleged homicide victims, and deposes in the court of law for giving expert testimony or opinions in various criminal or civil cases.

The identification of mass-disaster fatalities, such as those that occurred on 9/11, during Hurricane Katrina, earthquake, tsunami, and numerous plane crashes, has been carried out by forensic odontologists.

Although great attention was not paid to dental identification until recent times, the process has been in use for 2000 years.

Forensic odontology has become a vital and integral part of forensics that utilizes knowledge of dentistry for the identification of unknown living or deceased persons and unidentified remains.