49075554 forensic-odontology-dr-rizwan

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Forensic dentistry

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49075554 forensic-odontology-dr-rizwan

  1. 1. ForensicOdontology
  2. 2. By Prof.Pervaiz A RanaDeprtment of Forensic Medicine & Toxicology CMH Lahore Medical College
  3. 3.  Forensic Medicine and Odontology deals with the professional handling , examination, interpretation and presentation of medical and dental evidences that come before legal authorities Forensic Odontology is one of the fastest emerging sub disciplines within the broader subject of dental science. It requires special dental expertise not possessed by ordinary pathologist qualified only in medicine. It encompasses ethical issues and events related to the claim of negligence and malpractice by dentists and paradental professionals.
  4. 4.  History and status of Forensic Odontology Working of Forensic dental section Forensic Dental Anatomy Main applications Case discussion
  5. 5.  66 A.D.: Lollia Paulina’s body identified Casualty ID in Revolutionary War 1849  Vienna Opera House fire  Dental identification evidence first admitted in U.S. court system
  6. 6.  The department is divided into sub divisions like record section, cold storage, autopsy section, analytical, serologic and chemical examiner, they are interlinked with a chain of custody .
  7. 7.  ~ 32 teeth 4 tooth types  Incisors  Canines  Premolars  Molars Orientation/Size Root Structure
  8. 8. Canine crowncrown neck neck roo root t
  9. 9. cuspscrown Molarneck crown cuspsroots neck roots
  10. 10.  Each tooth has a specific number Each surface of the teeth are classified  Notes extractions, fillings, orient ation, etc. Primary dentition noted with upper case letters
  11. 11.  Are the remains human? If so, what are the sex, age, and race of the individual? Who is the person?
  12. 12.  Is it a tooth, or a portion of a tooth? Is it an animal tooth, or a human tooth? If human, what type of tooth is it, i.e., incisor, canine, premolar, or molar? Is it deciduous/primary, or permanent? Which quadrant does it come from, i.e., right upper, left lower, etc?
  13. 13.  Some variation is developmental, i.e., the tooth in question developed abnormally. Other variations are acquired at some time after birth. Such acquired variations can be the result of  trauma  erosion  occupational insult  dental work in a clinical setting.
  14. 14.  Abnormalities of eruption patterns. Abnormalities of shape (morphology). Any given tooth can have missing features, extra features, or atypical features. This can include bent teeth, anomalies in the number of cusps or roots, abnormal enamel deposition, etc. Abnormalities in the number of teeth. This can range from complete absence of teeth (adontia), to extra teeth, known as polydontia. Any given tooth may be absent in any given individual, a condition known as partial adontia. The presence of additional individual teeth is sometimes known as supernumerary teeth.
  15. 15.  Abnormalities in the spacing or position of teeth. Teeth can be crowded, have gaps (diastema) between them, or be rotated or misaligned. Long-term bulimics often have the appearance of teeth that are spreading apart – as the space between the teeth increases over time.. Abnormalities in the size of teeth. It is quite rare to have abnormally small (microdontia), or abnormally large teeth (macrodontia) – either as a complete set, or individually.
  16. 16.  Repairs, restorations, prostheses Dental staining & enamel variation  Coffee, colas, nicotine  Erosion  Occupational  Health-related issues  Diet composition Occlusal attrition Missing teeth  Premortem vs. peri/postmortem
  17. 17. Main Applications Individual Identification Mass Disaster Identification Bite mark Analysis
  18. 18. CUYAHOGA COUNTY 07-0000CORONER‘S OFFICE Dental records Photo Fingerprints
  19. 19.  Postmortem description is generated  Radiographs taken Possible identities known?  Yes: Comparison to antemortem data  Match strength determined  No: Biological profile generated
  20. 20.  Postmortem description is generated  Radiographs taken Possible identities known?  Yes: Comparison to antemortem data  Match strength determined  No: Biological profile generated
  21. 21.  Completed in the same manner as individual identification Organization of antemortem and postmortem data is essential Large scale problems can occur if no record available (radiological, DNA)
  22. 22.  Postmortem Team  Generates dental profile and radiographs Antemortem Team  Collects/organizes antemortem data Records Comparison Team  Compares postmortem and antemortem data
  23. 23.  Can be used to link a suspect to a crime Impressions left on food, skin or other items left at a scene
  24. 24. “Every contact leaves it’s trace”Said professor Edmond Locard (1877),founder and director of the institute of Criminalistics,University of Lyons,France
  25. 25.  Each dentition can produce variable impressions Change based on pressure and surface of contact Impressions from the same dentition
  26. 26.  Bite marks are photographed with a scale  Bite marks on skin are taken over repeated intervals Casts of impression are taken Impression traced onto transparencies Casts of suspects teeth are taken Comparison between suspect cast and bite mark
  27. 27.  Assailants Saliva Collection preservation & dispatch of saliva collected from bite site DNA profiling & Blood Grouping
  28. 28.  3D Bite mark analysis Automatic dental code matching OdontoSearch Automatic dental identification system
  29. 29. 3D scans of dentalcasts are used togenerate overlaysusing variouspressure anddeviation.
  30. 30. The overlays are compared with the photograph of thebite marks.
  31. 31.  Different people may have the same dental codes In the past, the strength of a match between a PM dental code and an AM dental code is based on the clinical experience of the dentist OdontoSearch provides an objective means of assessing the frequency of occurrence for a dental code
  32. 32. Genuine Matching Distance = 4.22 Query Image Matching Distance = 27.57 ImposterGenuine image has a smaller matching distance than the imposterimage. Images with smaller distance are included in the candidate list.
  33. 33. Feature Extraction 1 2 3 4 5 6 7 8 9 10 11 1213 14 15 16Atlas Registration 32 31 30 29 28 27 2625 2423 22 21 20 19 18 17 Matching Retrieval
  34. 34.  National Dental Program  In 1997, The Criminal Justice Information Services Division (CJIS) of the FBI created a dental task force (DTF). State Dental Program  Three states: Maryland, Washington, and California  Best Collectors of Dental Records (>10%)
  35. 35.  Bite mark analysis Identification Serological analysis of bite mark
  36. 36.  The most famous bite mark caseThe bite mark was on Transparent overlays Wax bite exemplarthe body of a victim superimposed
  37. 37.  Ted Bundy, was an American serial killer who murdered numerous young women between 1974 and 1978. He confessed to 30 murders, however the total amount of victims remains unknown. He would bludgeon his victims, then strangle them to death. He engaged in rape and necrophilia.
  38. 38.  in summer 1997 In a small town near yarkshaire wooden house catches fire and collapse, 2 bodies were found, remains were intermingled . Bodies were identified as 14 years old girl And 40 years old lady anatomical features and dental record.
  39. 39. •At ground zero, among 973 victims identified in the firstyear (with only one method), about 20% of victims wereidentified using dental records.
  40. 40. “Around mid-March, (of some800+ identified bodies) 90% wereidentified by dental records …If you post pictures of your lovedones on the bulleting boards/webboards, choose picture with abroad smile so that front teeth canbe seen. A better approach is topost dental X-ray films and leaveemail/phone number of thedentist.” ----- Tsunami Relief A forensic expert examines a film of the website teeth of a tsunami victim in Phuket of Thailand, on Jan. 11, 2005.
  41. 41.  A bite mark was  identified and preserved  impression was obtained  reconstruction of assailants teeth was done  Impression was compared with the record of suspects and finally the assailant was arrested .
  42. 42. State of Indiana v. Jeffery Jones IndianapolisPolice Departmentcase no. 5610144G
  43. 43.  A naked dead body of 38 years old lady was found near garbage container near her residence. Crime scene investigators (CSI) closely analyze the body and found a bite mark on her neck and left breast. Saliva sample was collected from bite mark Sample send for DNA profile analysis .
  44. 44. Conclusion:The DNA profile obtained from Item (s) M16 and M17 does not match the DNA profile of Item S1 and could not have originated from their initial suspect, Michael Willey.
  45. 45. Conclusion:The DNA profile obtained from Item(s) M16 and M17 was searched in the Indiana DNA Database and was found to be consistent with the convicted offender sample of Jeffery Jones (DOC inmate #974912).
  46. 46. Conclusion:In the absence of an identical twin, Jeffery Jones is the source of the DNA obtained from Items M16 and M17 to a reasonable degree of scientific certainty .
  47. 47. THANK YOU

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