Presentation is loading. Please wait.

Presentation is loading. Please wait.

Forensic Anthropology: Studying Bones Odontology & Facial Reconstruction

Similar presentations


Presentation on theme: "Forensic Anthropology: Studying Bones Odontology & Facial Reconstruction"— Presentation transcript:

1 Forensic Anthropology: Studying Bones Odontology & Facial Reconstruction http://people.stu.ca/~mclaugh/skeleton8a.GIF

2 One of the major role of a forensic odontologist is to use dentition to identify individuals by comparing the unique aspects of the victim’s teeth with pre-death dental records. Teeth are also excellent sources of DNA for identification purposes.  Forensic odontology (Forensic dentistry) – the application of the arts and sciences of dentistry to the legal system.

3 Anatomy of Oral Cavity: Maxilla – upper jaw Mandible – lower jaw Forensic Odontology > Body Identification

4 Anatomy of Oral Cavity Primary dentition  Baby teeth or milk teeth  20 teeth Forensic Odontology > Body Identification

5 Permanent dentition  Start at 6-8 years old  32 teeth Anatomy of Oral Cavity Forensic Odontology > Body Identification

6 Anatomy of Tooth Crown Root Enamel Pulp Cementum Contains DNA Forensic Odontology > Body Identification

7 Decomposition Problems - Fire Destruction from fire  Teeth can be shielded by a closed mouth  Temperature Effects:  400 O F = 200 O C – Teeth become brittle  900 O F = 480 O C – Teeth disintegrate  1800 O F =980 O C – Cremation temperature  2000 O F = 1100 O C – Dental gold melts  2200 O F = 1200 O C– Porcelain melts

8 Identification: Why Teeth ? 1.Resist destruction and decomposition 2.Show individual characteristics 3.Antemortem records available  Written  X-rays  Casts

9

10 A body is identified by comparing teeth and bone structures of the body to the dental records of the suspected individual. Forensic Odontology > Body Identification

11 A body is identified in 3 steps: 1. Postmortem examination of the body 2. Locating the antemortem dental records 3. Comparing the body to the dental records Forensic Odontology > Body Identification

12 Dental Identification Unique –No two individuals have identical dentitions –Dental care rendered is often unique –Identification can sometimes be made from one tooth Durable –Teeth most durable part of human body –Remains after decomposition, fire, or trauma

13 Dental Charts and X-rays Using a pre mortem x-ray and a dental chart - any major construction is marked on the dental chart Using a post mortem x-ray and a dental chart - features are also marked Comparative overlays of teeth angles and separations are also used to positively identify decedents

14 Postmortem Examination 1. Presence/absence of tooth Each tooth or socket is examined individually and the following is recorded: 2. Socket present or healed  Healed socket = past removal  Present socket = recent removal 3. Erupted vs. Unerupted 4. Filling or Crown Material Forensic Odontology > Body Identification

15 Unique Characteristics Restorations Fillings: –Amalgam, gold, resin, porcelain Crowns, bridges Gums Root Canals Missing Teeth Unerrupted Spaces Arch width

16 Unique Characteristics Dental Erosion enamel lost on palatal surface From bulemia, chronic alcoholism, gastric problems, etc. due to repeated vomiting, which causes acid erosion of the teeth. 

17 Unique Characteristics Tetracycline was taken while teeth were forming (uppers were stained also; note poor porcelains). Tetracycline = antibioic. Used to be used to cure ear infections in children. 

18 Unique Characteristics Pipe Smoker – tooth wear 

19 Unique Characteristics Occupational – Electrician stripped wire with teeth. Also see in seamstresses who hold pins in teeth. 

20 Unique Characteristics Regional Methods: Russia (earlier in history – former Soviet Union) 

21 Unique Characteristics Smoker + poor dental hygiene 

22 Two Main Uses 1.Identification 2. Bite mark analysis of remains

23 Antemortem Postmortem Comparisons 

24 Postmortem Examination After examination of teeth, they should be photographed and X-rays should be taken. Forensic Odontology > Body Identification

25 Comparison Postmortem exam compared to antemortem records. A statement is made about each tooth: Different with no explanation Consistent Different with explainable differences Forensic Odontology > Body Identification

26 Characteristics of Bite Marks:  Usually shape of two half moons (upper/lower)  Usually composed of 6 upper / 6 lower teeth Forensic Odontology > Bite Mark Identification

27 Characteristics of Bite Marks:  Antemortem (diffuse bruise) Perimortem (defined bruise) Postmortem (no bruise)  Only persists 8 hours on living person Forensic Odontology > Bite Mark Identification

28 Comparison of Bite Marks: 1. Photographic overlay of suspect’s teeth and bite mark. Forensic Odontology > Bite Mark Identification

29 Comparison of Bite Marks: 2. Compare mold of suspect’s teeth to bite mark or impression of bite mark. Forensic Odontology > Bite Mark Identification

30 Collection of Bite Marks 1. Identify as potential bite mark 2. Collect swabs 3. Photograph bite mark 4. Make an impression of bite mark  ABO blood test, amylase detection  DNA analysis Forensic Odontology > Bite Mark Identification

31 Famous Bitemarks Ted Bundy

32 Famous Bitemarks And Ted Bundy’s Teeth & Bitemark

33 FACIAL RECONSTRUCTION Facial features can be built upon a skull to assist in identification. Erasers are used to make tissue depths at various points on the skull. Clay is used to build around these markers and facial features are molded.

34 Forensic Artist and Missing Children · If a child is missing for a long period of time, or an unidentified skeleton of a missing child is found, the forensic artist is called upon to help make a sketch of the missing child. · In cases like these, when the forensic artist needs to work from an old photograph or a skull, a facial reconstruction artist is called to help. Picture: www.epm.ornl.gov/viz/apps/f- skull.jpg · The facial reconstruction artist uses either a 2D or 3D technique to construct the face of a missing child from a skeleton, or an old photo. Picture: www.headsketch.com

35 2-Dimensional Facial Reconstruction Picture: www.crimelibrary.com/forensics/art/images/Two-dimensional-facial-reco.jpg Procedures: · The unidentified skull is placed on a stand, in the Frankfort Horizontal position. · Tissue markers are placed on the skull. · A ruler is placed beside the skull. · Photos are taken of the skull’s frontal and profile views. · The photos are taped side by side, in the Frankfort Horizontal position, on two separate flat wooden boards. · Transparent natural vellum sheets are taped down on top of the photographs. · Following the skull’s natural contours, and using tissue markers as guidelines, the forensic artist creates a sketch of the unidentified person. · Approximate measurements for the mouth, nose, and eyes are made. · Hair type, and style are determined by other evidence collected from the crime scene that give clues as to the kind of life the unidentified person led.

36 3-Dimensional Facial Reconstruction Pictures: www.forensicartist.com/ hep/clem/3drecon.html. Procedures: · A skull is placed on a workable stand in the Frankfort Horizontal position. · Referring to tissue depth data previously taken, artificial eyes are centered in the skull’s eye sockets. · Tissue markers are glued right onto the skull. · Following the skull’s contours, and restrictions set by the tissue markers, clay is placed directly on the skull. · Measurements are made to determine mouth and nose thickness, length, and width.

37 3D Reconstruction Finishing Touches · Any information compiled from forensic anthropologists about the deceased such as the geographical locations of where he/she lived, or his/her occupation is used to complete construction. · Clay or wig is put on the skull to create hair. · The completed face is photographed. · The forensic artist now takes over and sketches the constructed face. Picture: www.crimelibrary.com/forensics/art/images/11-15-1.jpg Picture: www.troopers.state.ny.us/WntdMiss/Poster/Unidentified/caledonia.html

38 Computer Generated Age Progression Picture: www.ncsd.com/MissingChildren/mort-today.JPG · If computer software is used, the artist can use image enhance to add features such as eyeglasses, mustaches, beards, hats, different hair styles, and numerous other items on the photo. · Computer programs such as Photoshop are used to paint directly on a digitized photograph of the victim. Picture: www.chilhavisto.rai.it/CLV/img/ C/Celentano/grandi/AGING.JPG

39 Facial Reconstruction Skull can be scanned into a computer and "fleshed" by computer reconstruction to give likely facial appearance in life. Unfortunately eye color, hair color and lips are independent of bony structure.

40 Pearl was a female who died in her early forties approximately three hundred years ago. She was Caucasian, of European ancestry and stood about 5'1". Her dental health was extremely poor and she had lost 63 percent of her teeth prior to death. She had no teeth on either side of her jaw. This was most important as the loss of those teeth would evidence themselves in the final reconstruction as sunken cheeks. Of her remaining teeth, the condition was poor and she had several abscesses. During her lifetime, there are indicators that she also suffered from acute infections, rickets, sinusitis, an upper respiratory infection, arthritis, and gout. Whew--all this in an era when aspirin didn't exist! On the other hand, it was determined that she was very muscular, as the ridges on her long bones were very developed.

41 The artist utilizes proper tissue depth data determined by race, gender, and age. Artificial eyes are placed in the skull’s eye sockets, centered and at the proper depth. The tissue markers are glued directly onto the skull. Clay will be systematically applied directly on the skull, following the skull's contours; paying strict attention to the applied tissue markers.

42 Various measurements are made, and logged, to determine nose thickness/length, mouth thickness/width, and eye placement. Information such as geographic location of where the deceased lived, his or her lifestyle, and the various information provided to the artist by the Forensic Anthropologist and other professionals, is heavily relied upon when completing the reconstruction.

43 This woman had missing side teeth and a small jaw. Hair is added by applying clay or a wig. Various items (glasses, clothing, hats) may be applied to better accentuate the features of the individual. This method can be very successful.

44 Animal Facial Restoration Determining what T Rex looked like using the bone formation. From this: To this:


Download ppt "Forensic Anthropology: Studying Bones Odontology & Facial Reconstruction"

Similar presentations


Ads by Google