Forensics

Question 1

What are 3 essential characteristics of the human dentition which give them a certain uniqueness

Answer 1

Genetic racial characteristics
Chemical and structural modifications resulting from disease processes
Dental treatment

Question 2

What are the 2 types of victim identification

Answer 2

Comparative identification
and
Post-mortem dental profiling

Question 3

What is Comparative identification?

Answer 3

Used to establish that the remains of a decadent and a person represented by antemortem dental records are the same individual.

Question 4

What is Postmortem dental profiling?

Answer 4

Cases where antemortem records are not available and no clues to the possible identity exists

Question 5

In Comparative identification there are 2 types of discrepancies

Answer 5

Explainable discrepancies
Unexplainable discrepancies

Question 6

What is the differance between explainable and unexplainable

Answer 6

Relate to the time elapsed between antemortem and post mortem - explainable

unexplainable - Tooth is not present on the antemortem record but present on postmortem record

Question 7

What are the 4 possible conclusions of comparative identification

Answer 7

Positive Identification ( no discrepancies )
Possible Identification ( antep + postp consistent features - but 100% positivity can not be reached due to quality of records or antp evidence )
Insufficent evidence ( not enough of info to form basis for a conclusion )
Exclusion (ante p and post p are clearly inconsistent)

Question 8

What are a few problems with dental identification?

Answer 8

Absence of antemortem records
Absence of acquired dental traits for identification
Poor quality dental records
Not all teeth recovered in postmortem situation
Fire can result in irreversible changes to restorations and teeth

Question 9

What is postmortem dental profiling?

Answer 9

Used when there are no antemortem records and other methods of identification are not possible, The forensic odontologist can assist in limiting the population pool and thus increase the likelihood of locating antemortem dental records

Question 10

what type of information can postmortem dental profiling provide?

Answer 10

The deceased age
Ancestry background
Sex
Socio-economic status

Question 11

How does postmortem dental profiling assist in sex determination?

Answer 11

Microscopic examination of teeth can confirm sex by the presence or abscence of Y-chromatin and DNA analysis.
- Amelogenin is major matrix protein secreted by ameloblasts
- Females have 2 identical AMEL genes
- Males @ non-identical genes

Question 12

What are some other methods of dental identification?

Answer 12

Denture/appliance labeling
DNA identification
Dental materials ( addition of kevlar fibers ) this method requires good dental records
Ruguscopy - study of palatal rugae patterns

Question 13

What are the 2 types od DNA identification

Answer 13

Genomic and mitochodrial

Genomic - from nucleus of each cell
commonly used on forensics cases

Mitochondrial - Maternally inherited
there is a high number of copies of each cell due to high number of mitochondria present in most cells

Question 14

Advantages od denture labeling

Answer 14

• Identify unknown denture wearers in cases involving amnesia or senility, psychiatric cases
• In cases of lost and found
• To provide a rapid and accurate method of identification where fingerprinting is not possible
• In dental laboratories and clinical practices where dentists and technicians can easily identify a marked denture

Question 15

What are the 4 types of denture markings?

Answer 15

Engraving
Scribing
Writing
Inclusion

Question 16

What are a few guidelines with regard to denture markings?

Answer 16

Denture strength must not be compromised
Markings must withstand fire
Markings must be visible and durable
It must be easy , efficient and inexpensive

Question 17

Dental Age estimation uses what 4 diagnostic methods to examine age-related changes in teeth

Answer 17

Mophologic, histologic, radiographic, biochemical.

Question 18

Name a radiographic method for age estimation

Answer 18

Atlas style chart by Schour and Massler.

Question 19

Schour and Hoffman found that the pattern of what under normal conditions followed a reliable sequence of growth.

Answer 19

Calcification of dentition

Question 20

What is the Atlas style chart by Schour and Massler?

Answer 20

A summary of the development of the human dentition consisting of 21 diagrams with an age range from 5 months in utero to 35 years

Question 21

Advantages and disadvantages of the atlas style chart by Schour and Massler

Answer 21

Advs
- Simple system to follow
- Required no major specialised training
- Made use of readily available diagnostic aids

Disadvs
- Atlas Based system are based on the premise of ‘ one size fits all ‘

Question 22

Name 3 other radiographic methods

Answer 22

Moorees
Demirjan
Ubelakers dental chart

Question 23

What is the main advantage AlQatani revision of moorrees system.

Answer 23

Availability of diagrams for each year of development from ages 1 to 23

Question 24

The histological method of age estimation is based on what morphological and histological changes of the tooth. ( Gustafson Method )

Answer 24

• Amount of occlusal attrition
• Loss of periodontal attachment
• Deposition of Secondary Dentine
• Cemental apposition at the root apex
• Root resorption at the apex
• Dentine translucency

Question 25

What are some limitations of Gustafsons Method?

Answer 25

• None of the variables could be used alone expect dentine translucency
• Training in histology is problematic
• Require special equipment
• When only tooth is used the age range is increased
• Age range also increased in teeth over 50 years of age

Question 26

What is a Bitemark?

Answer 26

It represents a pattern of injury or makring produced by teeth during the biting process

Question 27

What 3 characteristics are involved in bite mark analysis?

Answer 27

Gross characteristics ( human or animal )
Individual characteristics ( size of tooth, rotated teeth )
Accidental characteristics ( chips and imperfections caused by attrition, abrasion and trauma )

Question 28

How can a bitemark be identified?

Answer 28

Gross features
- Circular/elliptical
- Central are of ecchymosis – because of sucking action )
Class features
- Incisor = Rectangular mark
- Canine = Triangular mark
- Premolar/Molar = Spherical/pointed

Question 29

What are the 4 methods of bitemark analysis?

Answer 29

• Direct macroscopic and microscopic comparative analysis ( mnost accurate and feasible bite mark analysis )
• Various overlay techniques
• Computer- generated comparisons
• 3D computer-assited programs

Question 30

Analysis sequence of bitemarks?

Answer 30

Recognition ( human or animal bitemark )
Documentation ( photogaphy )
Evidence collection and preservation ( DNA swabs and impressions )
Physical dental profiling of evidence ( bitemark )
Physical dental profiling of the known evidence ( suspect )
Compare evidence and suspect data
Drafting of report and submission

Question 31

What are a few drawbacks of bitemark analysis?

Answer 31

Parameters - Quality of patterns, type and quantity of material available for analysis, presence of recognisable dental features, variations of bite marks

skin is highly variable in terms of anatomical location and highly visco-elastic

Question 32

Risk factors contributing child abuse?

Answer 32

Stress
Unemployment
Poverty
Overcrowded living spaces
Substance abuse

Question 33

What are some extra-oral signs of physical abuse?

Answer 33

Bruising
- Cheek is the most traumatized
Burns
- Electrical, thermal or chemical
- Burns inflicted using cigarettes
Bitemarks

Question 34

Intra-oral signs of Physical abuse?

Answer 34

Soft tissue trauma
- Injuries may occur on the tongue, lips, hard or soft palates, mucosa, frenum, gingiva

Hard Tissue trauma
- Severe trauma to the lower face may loosen teeth, completely displace them, and cause fractures of the teeth
- Discoloured teeth, indicating pulpal necrosis
- Fractures of the mandible, maxilla and other cranial bones can also be found in cases of child abuse

Question 35

what are some indications of sexual abuse Intra-orally?

Answer 35

Gonorrhea, Syphilis, Chlamydia, Human Papilloma Virus and Human Immunodeficiency Virus.

Question 36

What is the type of child neglect dentists focus on?

Answer 36

Medical care neglect - Dental neglect

Question 37

What are the signs of Dental Neglect

Answer 37

Poor oral hygiene
Periodontal disease
Halitosis
Early childhood caries
Odontogenic infections
Apthous lesion due to nutritional deficiency