1.2 Identification of Burnt Victims by Their Teeth

Hello there mates! Welcome back.

So now that all of you guys already have the general idea or overview of what forensic odontology is all about and what they do, let us take you deeper into the matter on how they can actually identify unknown burnt victims just by simply analysing the victims' teeth and the remaining parts of their oral regions. How awesome is that?

P.S. Don't be alarmed by 'bombastic' words used here. Simply just refer to the glossary we provided for you at the end of this post. ;)

So as you all know, teeth are coated in enamel, a durable substance which is the hardest substance within the body. Because of this resilience, teeth outlast tissues and organs as decomposition begins. They can survive high temperatures and extreme conditions (even in the events of fire and explosions); which mean even death it is likely that some or all of our teeth will usually survive. When skeletal remains are found teeth are almost always present. This makes the use of dental records a reliable source of decedent identification. Forensic odontologist will use x-rays, dental casts, and even a photograph of the person’s smile to compare the remains to the suspected victim. 

The more complex dental work someone has received throughout his or her lifetime the more likely the forensic odontologist will be able to establish positive identification.

So to make it easier for you guys to understand the forensic postmortem dental examination process, we will take it into smaller parts.




  A. Examination of the Oral Tissues



         

     1.  In certain circumstances, the examination can begin at the site where the body was found or a 

          return trip may be warranted. A forensic odontologist may be able to help locate and 

          identify dental remains that are decomposed, charred or traumatically mutilated. Some of the 

          fragments may appear to be burned pieces of wood or other debris.

     2.  A single tooth, jaw fragment or even a portion of a tooth may be vital to the identification.

        
     3.  As easily as teeth break down throughout life, they will outlast all other body tissues after death.
        
     4.  Postmortem head and neck x-rays (or full body x-rays) may locate dislodged teeth or fragments. 
          X-ray examination of dirt or charred debris may also reveal fragmentary evidence.

     

When the body is badly burnt. access to the teeth is very difficult as the tissues are very rigid. Hence, the jaws need to be carefully resected or removed. Resection of the jaws should be accomplished if there is no open casket or viewing of the body. Caution is advised in resecting heavily burned or calcined jaws since they are extremely fragile. Fixation with clear acrylic spray is recommended.

By resecting the jaws, it allows the forensic odontology to accomplish a more complete and comprehensive examination as well as to be able to obtain a better quality of X-rays and photographs. If the jaws need to be retained for a period of time, they may be 
preserved in 10% formalin.




   B. Preparation of Postmortem Records 


           This needs to be done by several methods with proper requirements such as:





   1. Photographs.

• Full face.
• Close-up of the anterior or front teeth.
• Right and left lateral views of the teeth in occlusion or their proper bite.
• Views of the occlusal or chewing surfaces of the teeth in the upper jaw and in the lower jaw.
• Close-up photography of any additional features which may be important.

       
   2. Radiographs or x-rays.

• Essential to any forensic dental examination.
• Exposure time is reduced by 1∕3 for resected jaws and 1/2 for skeletonized jaws.
• X-ray examination is mandatory for estimation of age of the victim.

   3. Notes and charts.

• A dental chart should be prepared indicating all pertinent information.
• This information should include, but is not limited to:

          - Which teeth are present and which are missing.
          - Which teeth are restored or filled, what the restoration or filling material is, and which surfaces
             of the teeth are involved.
          - Indicate if root canals have been performed.
          - Describe any prosthetic and/or orthodontic appliances.
          - Describe the location and size of the decayed surfaces (cavities) of the teeth or if there are any 
            chipped or fractured teeth.
          - Describe any malpositions or rotations of teeth.
          - Describe unusual anatomy or shapes of teeth.
          - Describe the occlusion (the manner in which the teeth bite together).
          - Describe any oral pathology or other anatomic features which may be of potential importance.

*A sample of a dental chart.*

   4. Study models or casts of the teeth.

• Impressions can be taken of the victim’s teeth and then casts are made by using dental stone.
• It is usually not necessary or practical to take impressions of the victim’s teeth. However, there have been many occasions where casts have proven to be very valuable.
• The consulting forensic odontologist will decide if this procedure is warranted.

C. Securing of Ante Mortem Records

   1. Types of ante mortem records.

     (i)  X-rays

• X-rays are the most important antemortem records. Recover and submit all x-rays, including those x-rays taken 10-20 years ago. These x-rays may reveal additional information and may compare more favorably with the postmortem x-rays of the remains. 

• Obtain the original x-rays if at all possible. The dentist should duplicate the x-rays and retain the duplicates for his/ her records. The original film should be a better quality x-ray than the duplicate. 
• Obtain the most recent antemortem records. Most individuals have probably been treated by more than one dentist throughout their lifetime. 
• If conventional dental x-rays are unavailable, recover medical or chiropractic x-rays that may show the teeth. 
• Electronic transmission of scanned images of dental x- rays saved as bitmap files can be accomplished when expediency is required. An initial rule-in or rule-out comparison can be made of the electronic image on screen. The original films can be sent later if necessary.

    

   (ii) Dental charts

• Obtain the original dental chart if possible. If the dentist sends a copy, make sure the copy is legible.
• Dental charts can be very valuable, but the forensic odontologist must be aware that there may be errors incorporated into the chart by the dentist, the dental assistant or the hygienist making the entry. For this reason, x-rays are a much better means of making a comparison.

   (iii) Study models or casts of the teeth

• If the dentist has retained models, they can be very valuable. If the individual has seen an orthodontist, there may be a very good possibility of obtaining study models.

   (iv) Photographs

• Many dentists obtain photographs of their patient’s teeth as a means of documenting dental condition.
• Family snapshots, graduation, wedding or military pictures may reveal a “smiling photograph.” Teeth may be visible and disclose a missing, discolored, broken or chipped tooth. 

Hehe. We find this picture very funny. But the perfect teeth though. Ughh. #jelly!!!

   (v) If partial dentures or full dentures are involved, request that all additional sets 

        of dentures be recovered. A bite splint, mouth guard or orthodontic retainer should             also be recovered. 

THIS.IS.PRETTY.COOL!!! Does anyone know where we could get this amazing vampire denture?!?! Here's an idea for the upcoming Halloween!

  2. Recover all ante mortem records available 

• (including charts, x-rays, photographs and study models). 
• X-rays that may be requested are bite-wing x-rays, periapical x-rays, a full mouth series of x-rays (consists of periapical and bite-wing x-rays), a panoramic x-ray or a lateral skull x-ray.

*A sample of a Bitewing radiograph.*

*A sample of a Periapical radiograph*

   3. How to locate the treating dentist to 

     obtain the antemortem dental records.

• Inquire of family, friends and co-workers what dental clinic or dentist treated the individual.
• Inquire if the individual was treated or consulted a dental specialist (oral surgeon, orthodontist, etc.).
• Inquire if the individual had a dental insurance plan, a union dental plan, medical assistance or welfare benefits. This could lead to a dentist’s name.
• Examine military and prison records.
• Examine medical records to see if the physician has a record of the name of the dentist.
• In a small community, it may be necessary to contact all the dentists and inquire if they have treated this individual.

.  .  .  .  .

Are you??? GOOD. 

Now let's continue. We're ALMOST there I SWEAR!!!

   4. Comparison of the Antemortem and Postmortem Records 

       and X-rays

• The more areas of alterations or problems with the teeth, the greater the potential for a positive identification. With a perfect set of teeth (no decay, no fillings or restorations and a good occlusion or bite), or if there are minimal postmortem or ante mortem remains for examination, an identification may be more difficult. It may still be accomplished; however, meticulous attention needs to be paid to all minute detail. Excellent antemortem and postmortem x-rays are always preferable. 

• A positive identification must bear no unexplainable inconsistencies. Any differences in the antemortem and postmortem records must be thoroughly and adequately explained. 

• There is no specific number of characteristics needed for a positive identification. Occasionally, a single tooth or jaw fragment may possess the degree of specificity necessary to establish a positive identification. The final decision as to the degree of credibility of the dental identification rests with the judgment and experience of the forensic odontologist.

• Occasionally, the postmortem records are only consistent with the antemortem records, and a positive identification cannot be effected based on the dental information alone. However, a dental finding of “consistent” may be a significant contribution. It may be used in combination with other modes of identification (fingerprints, personal effects, anthropological or other medical findings, serology, etc.), and serve as corroborating evidence and increase the credibility of the final identification.

YAYYYYYY!!!!! YOU FINALLY MADE IT THROUGH THIS PART!!!

If you still got what it takes to be like one of those cool CSI crime investigators, then don't hesitate to continue on the next post.

You're one step closer to solving the crime!

References:

1. http://my.clevelandclinic.org/services/dental_care/hic_types_of_dental_x-rays.aspx
2. http://archive.ispub.com/journal/the-internet-journal-of-forensic-science/volume-4-number-1/methods-for-human-identification-in-forensic-dentistry-a-review.html#sthash.2eWBJONr.dpbs
3. http://edition.cnn.com/2013/02/13/health/burned-body-id/index.html
4. http://suite101.com/a/how-teeth-identify-the-dead-and-solve-criminal-investigations-a364078
5. http://www.ehow.com/how_8344456_identify-body-only-teeth-bones.html  

Glossary: *arranged alphabetically*

1. Antemortem: Before death
2. Anterior: In front/ front part
3. Anthropological: The scientific study of the origin, the behavior, and the physical, social, and cultural development of humans.
4. Enamel: The outermost layer of the crown part of the tooth. The hardest layer of them all.
5. Lateral: From sides to sides
6. Malposition: An abnormal position (for the teeth)
7. Mandatory: A must/obligatory
8. Meticulous: Showing great attention to details/precise/very careful
9. Occlusion: The biting surface; where the surface of the upper teeth meets the surface of the lower teeth when biting
10. Postmortem: Occurring or done after death