Medico-legal Investigation Skeletalization &Forensic Odontology

Skeletalization

The environment is more important than the time in this process.The environment is more important than the time in this process months: bone and tendon tags12-18 months: bone and tendon tags After 3 yrs: bare bone.After 3 yrs: bare bone. In temperate zones the bones will remain solid & heavy with the preservation of bone marrow in long bones for a number of years.In temperate zones the bones will remain solid & heavy with the preservation of bone marrow in long bones for a number of years. After years :After years : –Surface of the bone becomes dry & brittle –Marrow cavity will be empty.

The individual was recovered in a home with rats. Post-mortem bite marks are yellow, bloodless defects with scalloped edges.

Post-mortem Gnaw Marks on the Bone

Post-mortem vulture activity on a woman discovered in a wooded area. The tendon is visible through the hole while much of the muscle is absent. The yellow discoloration around the hole is consistent with beak marks

The skeleton is that of an adult male who was missing 1.5 months during late fall in the southeastern US. He was found in a wooded area. Gnaw marks are evident on several ribs.

Forensic Odontology An Introduction to Forensic Dentistry

Forensic Odontology is the application of dentistry in legal proceedings deriving from ANY evidence that pertains to teeth. FORENSIC ODONTOLOGY

Hardest part of body attached to jaws. Teeth serves to help digest food, act as a defense mechanism, etc. TEETH

Teeth Basics Tooth consists ofTooth consists of –Root –Root canal –Dentin –Enamel Types of teeth. Left to right: Incisor, Canine, Premolar, molar.

Forensic Odontology Human Dentition and Dental AnatomyHuman Dentition and Dental Anatomy –Enamel is the hardest substance in the human body –Full compliment of adult dentition of 32 teeth –Each tooth presents 5 surfaces in a visual examination for a total of 160 surfaces –Arranged in 2 Dental Sets called “arches” One Upper Arch = Maxillary JawOne Upper Arch = Maxillary Jaw One Lower Arch = Mandibular JawOne Lower Arch = Mandibular Jaw

Odontology

Odontology

Forensic Odontology Human Dentition and Dental AnatomyHuman Dentition and Dental Anatomy –Dental Arches are Symmetrical –Each Quadrant contains the same “number and type” of teeth

ChildhoodChildhood Adulthood Teeth through the years Primary teeth sprout from milk buds and are temporary. Once they fall out, permanent teeth as seen on the other side appear. Permanent adult teeth come in when primary teeth fall out; they are permanent because they establish roots inside the gums. Third molars come in around the mid teenage years.

Forensic Odontology The Human has the following:The Human has the following: –2 Incisors = sharp, flat, wide teeth for cutting –Cuspid = tearing, ripping and gripping –2 Premolar = 2 cusps for biting and crushing –3 Molar = 3-5 cusps (wide biting area) –Third molar = Wisdom (last tooth in arch)

Forensic Odontology Key to Dental Anatomy is:Key to Dental Anatomy is: –Orientation –Tooth Surface –Landmarks and Structures M = mesialM = mesial O = occlusalO = occlusal D = distalD = distal L = lingualL = lingual B = buccalB = buccal distal ←, mesial →, coronal ↑, apical ↓.

Forensic Odontology

Individual Characteristics Size of tooth Size of tooth Shape of tooth Shape of tooth Shape of root Shape of root Placement of tooth Placement of tooth Quantity of teeth Quantity of teeth Combinations of dental work done: Combinations of dental work done:  Crowns  Extractions  Bridge  Fillings  Root canals Various dental work

Analyzing Teeth The Universal System 1.Teeth are given a specific number. (Primary teeth are given specific capital letter) 2.Any dental work done on surface is noted 3.Sheets kept on dental file forever. When person is missing, files are transferred to the missing person’s office

Various Teeth Found

Why Teeth? Every human body ages in a similar manner, the teeth also follow a semi-standardized pattern. These quantitative measurements help establish relative age of person. Every human body ages in a similar manner, the teeth also follow a semi-standardized pattern. These quantitative measurements help establish relative age of person. Each human has an individual set of teeth which can be traced back to established dental records to find missing individuals. Each human has an individual set of teeth which can be traced back to established dental records to find missing individuals. Teeth are made of enamel (hardest tissue of the body) so they can withstand trauma (decomposition, heat degradation, water immersion, and desiccation) better than other tissues in body. Teeth are made of enamel (hardest tissue of the body) so they can withstand trauma (decomposition, heat degradation, water immersion, and desiccation) better than other tissues in body. Teeth are a source of DNA: dental pulp or a crushed tooth can provide nuclear or mitochondrial DNA to help identify a person. Teeth are a source of DNA: dental pulp or a crushed tooth can provide nuclear or mitochondrial DNA to help identify a person.

Dental X-rays

Forensic Odontology –Scope of FO is the following: Identification of unknown decedents by analyzing dentition (teeth), jaw structure, craniofacial bones, maxillofacial bonesIdentification of unknown decedents by analyzing dentition (teeth), jaw structure, craniofacial bones, maxillofacial bones Bite mark investigationBite mark investigation Examination of oral-facial trauma involving person/child abuseExamination of oral-facial trauma involving person/child abuse Medico-legal jurisprudence and expert witness testimonyMedico-legal jurisprudence and expert witness testimony

Who practices Forensic Odontology and what do they do? Forensic Odontologists  Must have DDS degree  Should have specialized training in the field through lectures (not required) Forensic dentists help:  Identify human remains (individual and mass)  Analyze bite marks  Bite marks are compared to known teeth molds to find origin of bite injuries  Estimate age of the victim and perpetrator  Trace dental malpractice Top: Forensic Odontologist analyzing animal teeth for comparison. Side: Seal for American Board of Forensic Odontology.

History The earliest known identification from teeth is in 1775 by Paul Revere.The earliest known identification from teeth is in 1775 by Paul Revere. Paul Revere made a silver bridge for one man. The man was killed in the Revolutionary War.Paul Revere made a silver bridge for one man. The man was killed in the Revolutionary War. Body was in a mass grave and identified by his silver dental work and hippo tusk.Body was in a mass grave and identified by his silver dental work and hippo tusk.

History of Forensic Odontology 66AD – First body identified using teeth66AD – First body identified using teeth –Lollia Paulina 1849 – Mass deaths at Vienna Opera House Fire1849 – Mass deaths at Vienna Opera House Fire –Dental evidence is first admitted into court system in US

Organizations of Forensic Odontology Bureau of Legal Dentistry (BOLD)Bureau of Legal Dentistry (BOLD) American Board of Forensic Odontology (ABFO)American Board of Forensic Odontology (ABFO) International Organization for Forensic Odonto- Stomatology (IOFOS)International Organization for Forensic Odonto- Stomatology (IOFOS)

Forensic Odontology Postmortem dental examination should include examination of:Postmortem dental examination should include examination of: –Missing, unerupted or extracted teeth –Restorations and prosthesis –Decay and broken teeth –Malposition, overlapping, crowding and spacing

IdentifyingIdentifying factors such factors such as cavities, as cavities, tooth pattern, tooth pattern, and general and general dental health dental health neglect neglect

Forensic Odontology Peculiar shapes of teeth Root canal on x-ray Bone pattern on x-ray Bite patterns

Odontology

Impressions from teeth found on skin or items left at a scene. Usually outline teeth placement. BITE MARKS

Forensic Odontology Forensic Odontology may include the study of bite mark patterns on the victim.Forensic Odontology may include the study of bite mark patterns on the victim. –Digital overlay is used to make a comparison.

Ted Bundy

List of Skull Bones for You to Know FrontalFrontal ParietalParietal OccipitalOccipital TemporalTemporal Zygomatic (and arch)Zygomatic (and arch) OrbitOrbit MaxillaMaxilla MandibleMandible