Forensic Odontology

        Application of Dental Expertise and knowledge to the legal systems i.e., for the purpose of law and order to prove or disprove something in the court of law is referred as Forensic Odontology.

    Forensic odontology, also known as forensic dentistry, is a specialized field of forensic science that involves the examination, evaluation, and identification of human remains, often relying on dental records and dental evidence. Forensic odontologists use their knowledge of dental anatomy, oral pathology, and dental records to assist in solving criminal cases and mass disaster victim identification.

Ancestry determination: -

Dental features can provide an individual’s ethnicity based on the shape of teeth. Chisel shaped incisors, Carabelli’s cusp, protostylid, peg shaping of teeth etc. can be used to determine race or ethnicity of individuals.  This can help the odontologist to aid in the investigation process. Dental characteristics like shoveling, scooping of the upper incisor are seen prominent in Asiatic Mongoloids and Amerindians.

Shovel or scoop shape appearance is mostly seen in Mongoloid population. There incisors have greater curvature than Caucasoids.

Caucasoids have narrow “V” shaped arch giving rise to crowding of teeth.

Negroids have small teeth, lower first premolar has two cusps, or even three.

Bite Mark Analysis: -

These marks are mostly seen in sexual assault cases. The forensic odontologists compare these bite marks on the victim’s body with the suspect’s dental model. Recognizing biting imprints on many materials, including food, leather, and wood. Using bite mark analysis principles to analyze weapon markings. Providing bite and weapon mark evidence as an expert witness in court.

Mass Disaster Victim Identification: -

These is mostly used in the identification of the individual just like fingerprints are unique every person’s dental alignment is difference. With the help of the antemortem dental records, the individual can be identified.  Teeth can resist decomposition therefore they can be found in any environmental condition.

Age Estimation: -

Forensic odontologists helps to identify the age of the unidentified body with the help of dental development, wear pattern and condition of teeth. For example, unidentified skeletal remains were found and it was found that the wisdom tooth or third molar is started to erupt, the fact is that the third molar will erupt at the age of 17-21. Therefore, the IO will get an idea about the age of the individual and which will help them to narrow down the investigation process.

There are several other methods to identify the age of the Individual: -

• Gustafson’s Method
• Amino Acid Racemization
• Radiographic method of Kvaal
• Dentin Translucency

Analysis of Dental Restoration: -

Dental restoration helps as an unique characteristic. Restorations like filling of the tooth with cement, crowns, or implanting of gold or silver tooth which makes the individual unique from others. Therefore, these findings will be compared with the dental records and the identification will be done accordingly.

Identification of Human Remains: -        

A forensic odontologist's main responsibility is to assist in the identification of deceased people when other techniques (such visual recognition) are rendered impossible by conditions like decomposition, trauma, or disfigurement. They accomplish this by comparing dental data of known persons with post-mortem dental findings.

Dental Trauma Assessmen: -

Forensic odontologists investigate dental trauma and injuries to offer information about the way of death or the origin of the damage. They can assist in ascertaining whether the trauma was caused by an assault, accident, or other events.

Comparison of Dental Records: -

To create a comparison with the unidentified person's dental features, forensic odontologists examine dental records, including X-rays, charts, and pictures. This procedure could result in a successful identification.

Sex Determination: -

Both male and female sexes have different tooth characteristics, including as morphology, crown size, and root lengths. The patterns of the skulls varies as well. These will assist in determining the sex for a forensic odontologist. Canines show the maximum difference. Also, with the help of DNA Profiling sex can be identified with the help of AMEL gene. With the help of Microscope, it has been seen that Females have the bar bodies present in the nuclei and bar bodies are absent in Males. 

Organisations related to Forensic Odontologists :

1. The Indian Association of Forensic Odontology (IAFO)
2. Indian Dental Association (IDA) 
3. American Board of Forensic Odontology (ABFO)
4. Scientific Working Group on Disaster Victim Identification (SWGDVI)

 

Case Study

NIRBHAYA CASE: DELHI GANG RAPE – 2013

Incident: - On December 16, 2012, while riding a private bus in Delhi, India, Nirbhaya, a 23-year-old woman, was the victim of multiple rapes. She had a male friend with her. She died on December 29, 2012, as a result of the terrible injuries she sustained in the violent attack. In a day, the suspects were located. Six males, one of whom was a minor, were convicted guilty.

Police Findings: - The Delhi Police called the Forensic Odontology department in Dharwad for help on January 1, 2013, in order to investigate bite marks that were discovered on the victim in the "Nirbhaya" case. The very following day, five adult men who were accused of being involved in the case's bite marks as well as dental models of them were given to SDM College of Dental Science & Hospital, Dharwad, by a sub-inspector from the Vasant Vihar Police Station in New Delhi. Bite marks are typically discovered in sexual assault cases. These bite marks can resemble fingerprints on the teeth that generated them.

Investigation: - The victim's body was found to have five or six bite marks, which were carefully examined and compared to the teeth of the five accused. In this inquiry, a computer-based 2D digital analysis was employed. After five days of examination and inquiry, a comprehensive report was given to the police indicating that a few bite marks may have been caused by the dentition of two of the suspects.

 

References :

1. https://www.sciencedirect.com/topics/medicine-and-dentistry/forensic-odontology
2. https://www.ijofo.org/article.asp?issn=2542-5013;year=2021;volume=6;issue=1;spage=1;epage=2;aulast=Uma
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6344795/