Lecture VI

Identification is essential when the deceased is decomposed, burned or dismembered.

The identification of the deceased individuals is an essential element in the process of death certification

Identification cases are not pleasant, especially when decomposition is concerned.

 Dental identification plays an important role in the identification of victims of disastrous events where there are massive numbers of victims.

The evidence derived from teeth are:  the age estimation (i.e., children, adolescents, adults)  identification of the person to whom the teeth belong.

 Criminal Investigation in criminal death cannot begin until the victim has been positively identified.  Marriage Individuals from many religious backgrounds cannot remarry unless their partners are confirmed deceased.  Monetary Payment of pensions, life insurance and other benefits relies upon positive confirmation of death.

 Burial Many religions require that positive identification be made prior to burial in geographical sites.  Closure Identification of individuals missing for prolong time can bring peace and closure to family members, that it is an essential component of the grieving process.

 The identification of unknown persons may start at a crime scene or during the autopsy the postmortem examination.  The postmortem examination consists of:  visual examination (cranial features),  x-rays ( dental features),  biological dental evidence (a complete or fragments of a jaw or a few teeth).

 Information gathered during this examination is documented in a written report.  This information is coded into a computer identification program that contains both antemortem (before death) and postmortem (after death) dental records.  The computer compares these records in an attempt to match the unknown with known records, or photographs.

 Comparison of pre- and postmortem data lead to one of the following situations:  Positive identification  Possible identification  Insufficient identification evidence  Exclusion of identification evidence

 Positive identification: There is no differences among items of antemortem and postmortem dental records are observed  Possible identification: There are common aspects among items of antemortem and postmortem dental records; however, sufficient agreement to establish positive identification is lacking.

 Insufficient identification evidence: There is insufficient evidence to reach a conclusion.  Exclusion of identification evidence: There are differences among items of antemortem and postmortem dental records which prevent the establishment of an identification

It involves pre- and postmortem comparison: 1. Dental comparison 2. Radiographic pictures 3. Finger prints 4. Palm prints 5. Foot prints 6. Serological identification 7. DNA identification

 Quality radiographs and accurate charting are the FIRST steps in providing a positive identification.  The documented information in the ante- mortem dental record should be recorded clearly, correctly, and specifically.  Dental professionals should to utilize universal abbreviations when documenting.  Dental professionals should document the detailed procedures conducted on patients.

 An identification begins with what is called an assumed identification, which means that the evidence is sufficient to expect who the deceased individual is (purse or wallet, witness, a person known to be missing).

 The individual’s dentist is located and dental records are requested.  People living in the deceased’s neighborhood can be helpful in locating the dentist.  Insurance papers, bills, and other means of communication from the dental office.

 poor individuals who are homeless are not so easily identified because dental records are limited.  Typically, they have been seen by various dentists, or emergency clinics; few have regular dentists.

 Due to circumstances of death or decomposition, visual identification by someone who knew the deceased is impossible.  This may require taking x-rays on the deceased and comparing them with x-rays of who the person who is supposed to be.

 Often, in burn cases, the evidence presented to the forensic dentist is minimal.  When teeth are subjected to high temperatures, the organic portion of the tooth, the dentin, expands and the surrounding enamel separates from the dentin.  The dental structures are so fragile that they require careful removal before x- rays can be taken.

 No complete dentition may be present, and there may be only:  portions of teeth,  restorations,  evidence of roots and sinuses that can be compared to antemortem x-rays without actual teeth.  Because of their unique nature, sinuses are often used for identification, especially if there is evidence of roots below them.

 A body was recovered from a fire pit, the burning was so complete that the investigation revealed several fractured pieces of teeth and the crown (minus the enamel) and a partial root of tooth No. 18.  In addition to the dental remains, pieces of bones revealed that the remains belonged to a young woman whose age and body size were consistent with the female who had been kidnapped.

 The tooth No. 18 was the key to the case. A few weeks before the kidnap, the victim’s dentist had placed occlusal amalgam restoration in tooth No. 18 and bonded it in place with a new dental resin cement. This was an unusual application of the product.  When the restoration and surrounding dentin were analyzed, it was determined to contain zirconium, which was one of the elements in the manufactured product. Her dentist testified that she had indeed placed the restoration and bonded it with this new dental resin cement.

 In addition, evidence of zinc oxide was found in the dentinal tubules and the dental charting by her previous dentist indicated that a zinc oxide base had been placed in that tooth nearly 10 years earlier. The successful examination of this case reveals to the importance of thorough and accurate dental charting.

 There are three categories examined for identification : The teeth, the periodontal tissue, and the anatomical features.

 The comparison of teeth includes: -tooth type (permanent, deciduous, retained primary, supernumerary), -erupted, unerupted or impacted -congenitally missing or lost ante- mortem/post-mortem, - the tooth position -crown morphology -root morphology and, - pathology.

 The root surfaces of teeth have unique shapes and bends that just may be the key to a positive identification.  Incidents such as plane crashes and explosions can damage the coronal surface of the tooth. A positive identification is made by comparing the pulp chamber and root morphology.

 The pulp chamber can be used to distinguish approximate age of the individual (size varies from children to adult teeth).  The root morphology along with the pulp chambers will assist in determining whether the tooth is from the maxillary or mandibular arch, and distinguishing if it is an anterior or posterior tooth.

Two dental radiographs. Left is taken after death; right is before death. The metal crown and dental structures have similar outlines

 Mandibular canal,  Coronoid and condylar processes,  Tempromandibular joint (TMJ),  Some pathologies (developmental cysts, salivary gland pathology, trauma, evidence of surgery, metabolic bone disease, focal or diffuse radiopacities).

Other factors used for a comparison:  gingival morphology and pathology,  periodontal ligament morphology and pathology,  the alveolar process and lamina dura.  the maxillary sinus,  anterior nasal spine,