Dental records and forensic odontology can be used to identify individuals and aid in criminal investigations. Teeth provide unique and durable evidence because they are resistant to heat, trauma, and decomposition. Forensic dentists examine dental records, bite marks, teeth, and other dental evidence to determine factors like identification, age, sex, and habits. Positive identification relies on sufficient unique dental characteristics matching between ante-mortem and post-mortem records, while exclusions can be as important as identifications. Teeth allow estimation of age through development, wear, and microscopic changes. Sex can be estimated through morphological traits and molecular analysis of cells from teeth. Forensic dentistry is an important tool for justice.

1. DENTAL
DETECTIVES
1

2. Criminals & Crimes
Terrorists and Terrorism
Frauds and Cheatings
Lead To
Loss of Lives, Prosperity & Peace
Dental Specialists enable rendering of
Criminal Justice

3. DENTAL DETECTIVES
ITS ALL ABOUT INVESTIGATIONS…
DR. NEERAJ TANEJA
Asso Professor
MDS, MBA, PGDFS

4. KEISER and NEILSON in 1970
It is a branch of odontology which
deals with the proper handling of
examination of dental evidence and
the proper evaluation and
presentation of dental findings in
the interest of justice

5. FDI says…
“ That branch of dentistry which, in
the interest of justice, deals with
the proper handling and
examination of dental evidence, and
with the proper evaluation &
presentation of dental findings ”

6. Where is it Used
Civil
Criminal
Research

7. Forensic Dentistry- A Historical View
Dates back 4500 years
First Recording in 2500
BC

8. More on History
•FATHER OF FORENSIC ODONTOLOGY
DR.OSCAR
AMOEDO
• "The role of dentists in the identification
of the victims of the catastrophe of the
Bazar de la charite“
1897
• L'ART DENTAIRE EN MEDECINE LEGALE
1898 - French
1899 - German

9. TWIGS OF FORENSICS
FORENSIC
ODONTOLOGY
Forensic
pathology
Forensic
toxicology
Wildlife
forensics
Forensic
Anthropology

10. Why Dentists?
10
PROCESS
SAME AS
THAT USED IN
DENTAL
PRACTICE
RECOGNITION
AND
EVALUATION
OF CERTAIN
CHANGES
OVER TIME
CONTINUALLY
COMPARE
CURRENT AND
PREVIOUS
RECORDS

11. ROLE OF FORENSIC
ODONTOLOGIST

12. Where and How?
• Human Remains
• Living Body
Identification
• Age and Sex determinationAge and Sex
• Victim AnalysisMass Disaster
• Bite
• Lip Prints
Marks and
Prints

13. Why Teeth ?
Hardest of all Human Tissues
Resistant to post-mortem & destruction
Contained in Small Area of the Body
Most stable biological evidence
Readily accessible for examination
No two individuals have identical dentitions - UNIQUE
Dental care rendered- UNIQUE
Teeth as Sources for Forensic DNA

14. Tooth at Different Temperatures
200oC
• Crown- Mottled
• Root- Light yellow
300oC
• Crown- Yellow
Brown
• Enamel- Cracks
• Roots-Dark
Brown, Destroyed
400oC
• Crown- Dark
Brown, Cracks
and Splits
500oC
• Enamel separates
from the crown
800oC
• Volume reduction
• Carbonization

15. and Beyond 800OC<915oC
Amalgam
Fillings -
Intact
>915oC
Gold
Alloys
Melt
1090oC
Porcelain
May
Survive

16. Power of Evidence

17. Locard’s Exchange Principle
"Every Contact Leaves a Trace“
"with contact between two items, there will be
an exchange."
• The value of trace (or contact) forensic evidence was first
recognized by Edmund Locard in 1910.

18. Dental Identification Kit
Protective
Clothing
Impression
Materials
Dental
Instruments
Photography Data
Recording

19. PhotoMacrographic Scale

20. PhotoMacrographic Scale

21. UV Lighting for Inspection

22. Comparison Microscope
Allows two sections to be viewed simultaneously at
exactly the same magnification so that a correlation
can be tested between the two

23. Dental Records

24. Introduction
• For Dummies
– Ante Mortem, Post Mortem
• Ante- Before
• Post- After
• Mortem- Death
• Dental Records
– Instrumental in Forensic Odontological Identification
• Record Content
– Exhaustive, Correct and Clearly Expressed

25. Dental Records- Include
Photographs
Intra Oral
Radiographs
Impressions Comparisons
Study
Models

26. Dental Identification

27. Principles of Dental Identification
Preliminary Evaluation
Postmortem Examination
Ante-Mortem Investigation & Data Collection
Comparison and Conclusion
Validation & Reliability

28. Preliminary Evaluation

29. Post Mortem DVI
• Clinical examination
• Post-mortem radiographs
• Photographs
• Charting and recording
PINK FORM

30. Ante Mortem
• Charting and recording
• Radiographs , models
and photographs
YELLOW FORM

31. Comparison & Conclusion
DISCREPANCY BETWEEN THE TWO RECORDS COMPARED SHOULD HAVE AN EXPLANATION.

32. Comparing – Ante & Post Mortem
POSITIVE IDENTIFICATION:
• Sufficient Uniqueness , no major differences
PRESUMPTIVE (POSSIBLE) IDENTIFICATION:
•Certain common features, enough information missing to establish a positive identification
INSUFFICIENT IDENTIFICATION EVIDENCE:
• Insufficient supportive evidence
EXCLUSION OF IDENTIFICATION EVIDENCE:
• Either explainable or unexplainable discrepancies, which results in inconsistencies that prevent the establishment of any
identification
Exclusion may be just as important as determination of positive identification

33. IDENTIFYING A
DECEASED
33

34. Identification of an Individual
Important to have ante-mortem records
Age estimation
Sex determination
Race and folk groups
Occupation , habits and social status
Illness and medication

35. What Helps
• Arrangement
– Type
– Rotated
– Mal Occlusion
• Mixed Dentition
– Eruption Sequence

36. What Helps
ARRANGEMENT OF TEETH:
- Type
- Rotated
- Mal-Occlusion
MIXED DENTITION:
- ERUPTION SEQUENCE

37. MISSING TEETH:
-Number and Type of
teeth missing
MALSHAPED TEETH:
- Fused
DIASTEMA

38. HEREDITARY CONDITIONS:
- Dentinogenesis
- Amelogenesis
- Malocclusion

39. TYPE OF TEETH:
Macrodontia/Microdontia
RESTORATION:
-Type - Gold, Tooth colored,
Amalgam, Porcelain
- Area of restoration
- Endodontic treatment

40. SUPERNUMERARY TEETH:
ADDITIONAL CUSPS:
-Cusp of Carabelli

41. Unusual Wear and Tear
Erosion
Abrasion
Unusual wear and tear can help identify various aspects

42. Habits
• Staining of Teeth
– Pan Chewer
– Betel Nut Chewing
– Smoking
• Pipe Smokers

43. Occupation
• Goldsmith or person working with
lead shows blue line in gums
• Green line – by Copper
• Black line – by Silver
• Cobbler, carpenters, electrician &
tailors have central notch in the
incisal edges of anterior teeth.
• Traffic police & flute player has
attrition of anterior teeth

44. Tooth loss before or after death
• Empty Sockets
– Unresorbed and
Sharp - lost after
death

45. Dentures – Identify Individual
• Different Properties of Dentures can be used
– Type of Material
– Marks and Names on dentures

46. Orthodontic Treatments
Fixed
Removable

47. Age Estimation

48. Systems for Age Estimation
• Dentition - one of the fourth system used in
estimating physiologic age
• Other three being
– Bone development,
– Secondary sexual characters,
– Stature and weight.

49. Systems for Age Estimation
Dentition
Bone
development
Secondary
Sexual
Characters
Stature and
Weight

50. Dentition for Age Estimation
Eruption Sequence
Deciduous Mixed Permanent

51. Methods for Age Estimation
• Gustafson G. 1966
• Sopher IM. 1976
• Harvey 1976.

52. Gustafson’s Method
• Age estimation in adults over 21 yrs of age
depends on the physiological changes in each
of the dental tissues
– Attrition
– Paradentosis
– Secondary dentin
– Cementum apposition
– Root resorption
– Transparency of the roots

53. • Changes are measured in degrees 0-3
– 0 : No Change
– 1 : Beginning of Changes
– 2 : Obvious Changes
– 3 : Maximum Changes
• Formula for Estimation
– Age = 11.43 + 4.56X
– X- The degree of changes
53
Gustafson’s Method

54. Histological Study of Transparent
Dentine

55. Below 20 years 21 – 30 years 31 – 40 years
Transparent Dentine of Root
< 20Y
• ABSENT
21- 30Y
• Attempted
Formation in
Apical 3rd
31-40Y
• Involving full
apical 3rd.
41-50Y
• beyond apical
3rd up to
middle 3rd of
root
51-60Y
• beyond
middle of the
root and
towards
cervical.

56. • Transparent Root
56
Miles Method

57. Age Determination at Death
• Boyde
– Works on the
incremental lines of
enamel
– Very effective upto
few months after
birth
This so-called neonatal line may be of extreme medico-legal importance in these cases

58. Pink Teeth
• Due to accumulation of blood breakdown products in the dentinal tubules
• It appears to take from 7 to 14 days before discoloration becomes
apparent
• May give some gross indication of time of death
• Violent death such as strangulation
• In forensic practice the phenomenon is most frequently seen in victims of
drowning

59. Other Methods of Age Estimation
• Teeth colour
• Calcium/phosphate ratio
• Number of dentinal tubules
• Flourescence from dentin and cementum
• Root canal shrinkage

60. Sex Determination

61. Traits for Sex determination
TRAIT MALE FEMALE
General size Larger Smaller
Supraorbital
ridges
Medium to
large
Medium to
small
Architecture Rugged Smooth
Orbits Square Rounded
Cheek bones
Heavier,
more
laterally
arch
Lighter &
more
compressed
Mastoid
process
Large,
prominent,
roughened
Smoother &
less
prominent
Forehead
Less
rounded
More
rounded
:

62. MALE FEMALE
Lower jaw Massive Less
massive
Chin Square Pointed
and
rounded
Symphyseal
height
More less
Angle
region
Averted Non-
averted
Lateral
angle
marked roughening
or ridged
appearance b’coz
of masseter
Attachment &
powerful closing of
jaws
More
rounded
attachment
surface
more
smoother
Ramus Broad Less broad
CONDYLAR
ANGLE :
Vary between male and female

63. Sex Determination- Dentition
• Can be determined by
dental pulp.
• Davidson bodies in the
nucleated cells of
polymorph in pulp cavity
• Saliva - cells are studied
by Barr & Davidson
bodies

64. 64
BARR BODIES – SEX CHROMATIN
INFANT FEMALE ADULT FEMALE ( > 20) NOT SEEN IN MALE

65. AMELOGENIN
• Amelogenin (Calcium Binding Protein) found in
developing tooth enamel
• Gen Females (XX) have two identical AMEL genes but the
males (XY) have two nonidentical genes e - on both the Y
chromosome in males and the X chromosome in females
• ISOLATING GENOMIC DNA FROM DENTAL CELLS TO
IDENTIFY GENE AMELOGENIN
• Helps in sex determination

66. The Y-CHROMOSOME
Nucleus of male cell with
fluorescent ‘Y’ chromosome
Nucleus of female cell with faint
fluorescence of the whole nucleus

67. Amino Acid Racemisation
.
• Helfman and Bada first suggested a relationship
between dentinal age and the extent of aspartic
acid racemization in dentine.
• Aspartic acid is an amino acid that has a rapid
rate of racemization
• Constant change in the ratio of L- and D-aspartic
acid at different ages and this D-L ratio may be
used for age estimation.
• Racemization rate of aspartic acid is high in root
dentine

68. Sex Estimation by Tooth Size
• Environment & population specific
• INCISOR INDEX = MDI2
* 100
MDI
1
– Higher in males
– Lower in females
• MANDIBULAR CANINE INDEX =
(mean m-d canine width in females + S.D.)
+
(mean m-d canine width in males – S.D.)
2
68

69. Determination of Race

70. CHINESE:
1.Wide arch
2.Enamel extension
between roots of molars
3.Five cusped third molars
4.Rooted deciduous molars
EUROPEANS:
1. Narrow arch & crowding
2. Cusp of Carabelli
MONGOLOID:
1.Occlusal enamel pearls in
premolars
2.Missing mand. incisors
3.Shovel-shaped incisors
AMERICAN INDIANS:
1. Marked attrition
2. Shovel-shaped incisors
3. Large teeth
SOUTH AFRICANS: Tall pulp chambers
Significant Traits for Race

71. ABO Blood Group Determination
• Different Methods Used
– Absorption elution technique
– MIXED CELL AGGLUTINATION TESTS
– CELL AGGLUTINATION TESTS

72. Blood Group Substances
• In Soft Tissues
– Water-soluble ABH substances
– Found in abundance in the mucous acini of salivary glands of
secretors
– Absent in serous acini of non-secretors
– Restricted role due to putrefaction
– Mixed cell agglutinations or Elution-absorption is used
• Bone and Teeth
– Resistance to putrefaction
– Pulverization of the sample, extraction of the blood group
substances using various solvents.
– SOLVENTS: Processing the tooth powder with
 1% HCl acid and alcohol, 20% EDTA and alcohol, Acetone extraction

73. The Luminol Reaction
• Fluorescent Chemical
– Can reveal blood stains when sprayed in dark on
the suspected item
– Sensitive to pickup minute blood trces

74. Saliva
• Samples obtained from cigarettes, bidi ends & utensils
• Samples from victims as well as suspects in case of sexual crimes
• Presence of saliva can be confirmed using
- The starch-iodine test
- Phadebas test
BLOOD GROUP SUBSTANCES IN SALIVA:
• ABH blood group substances in fairly high concentration seen especially
in individuals of ‘O’ group (secretors)
• Screening test with anti H
• Tests for ‘A’ & ‘B’ substances using
- Absorption-elution method for A, B, H (small samples)
- Agglutination-inhibition (large samples)

75. BITE MARKS
75

76. Bite Mark
‘a mark made by teeth either alone or in
combination with other mouthparts’
Or
‘a physical alteration in a medium caused by the
contact of teeth’

77. Classification
• Cameron and Sims (1974)
– Non Human (animals)
– Human
• In food stuffs (e.g. in part eaten food stuffs abandoned by
offenders at scene of crime).
• On non-biological objects (e.g. Pencils, pipe stems,
detonators)
• In human skin
• Non criminal (erotic bites)
• Criminal (ordinary and sexual assaults) which may be
• Offensive (upon victim by assailant).
• Defensive (upon assailant by victim)

78. 78

79. Description of Bite Mark
Demographics Name of victim, Case Number, Date of examination,
Referring agency, Person to contact, Age of victim, Race of
victim, Sex of victim & Name of examiner(s)
Location Anatomical location,
Surface contour: flat, curved or irregular Tissue
characteristics
Underlying structure: bone, cartilage, muscle, fat, Skin:
relatively fixed or mobile
Shape Shape of the bitemark should be described; e.g. essentially
round, ovoid, crescent, irregular, etc
Color Color should be noted; e.g. red, purple, etc.
Size Vertical and horizontal dimensions of the bitemark should be
noted, preferably in the metric system.
Type of Injury Petechial hemorrhage: Contusion (ecchymosis), Abrasion,
Laceration, Incision, Avulsion, Artifact

80. Collection of Evidence from Victim
Photography Name of victim, Case Number, Date of examination,
Referring agency, Person to contact, Age of victim,
Race of victim, sex of victim & Name of examiner(s)
Salivary Swabbing
Impressions
Tissue Samples Tissue Fixative:10% Formalin is a common fixative
Other Information

81. Collection of Evidence from Suspect
History history of any dental treatment subsequent to, or in
proximity to, the date of bitemark.
Photography good quality extraoral photographs should be taken,
both full face and profile.
ABFO No. 2 scale should be utilized
Intraoral photographs preferably would include:
Frontal view , Two lateral views, Occlusal view
of each arch, Any additional photographs
Extraoral Examination
Intraoral Examination
Impressions
Sample Bites
Study Casts

82. Bite Marks on Food
• Photograph
• Wash Saliva
• Send for blood grouping
• Apply a lubricant on the
food stuff
• Pour Plaster on it
• After drying remove the
cast
82

83. Food Bite Marks- Process
PVS
polyvinyl
siloxane
impression
Cotton
Backing
Dental
Plaster Mix
Impression

84. Bite Mark Analysis
84

85. Methods
• Overlay Fabrication
– Hand Tracings
– Photocopy technique
– Computer Scanner
– Radiography
– CT Scanning

86. Non Metric & Metric Analysis
Non Metric Metric

87. Photography in Bite Marks
• Visible Light Photography
• Digital Photography
• Non-Visible Light Photography
– Ultra violet photography
– Infrared Photography

88. Bite mark located on deceased victim’s abdomen using normal
full-flash photography.

89. Same Bite Mark using ALI

90. Normal “room light” photograph of palm side of two-month-old
infant victim of child abuse; bite mark pattern is almost
indiscernable

91. Same bite mark using forensic light source at low-angle incident
lighting. Note improved visualization of separations (striations) between
teeth.

92. Black-and-white view of abdominal bite mark exposed with
fullspectrum room light
bite mark using forensic light source at low-angle incident
lighting. Note improved visualization of separations (striations) between teeth

93. • Epiluminescence microscopy is a
dermatologic technique
developed for evaluation of
pigmented skin lesions
• This technique, through rendering
the stratum corneum translucent,
can aid in the visualization and
photographic documentation of
bite marks
Epiluminescence light microscopy (ELM) in Bite Marks

94. DNA in Dental Identifications
• Teeth- Excellent source of DNA
• DNA Extraction
– From calcified tissues by CRYOGENIC GRINDING
METHOD and PCR analysis is done
– "RFLP"- Restriction Fragment Length Polymorphism
Technique
• DNA Comparison
– With known Ante-Mortem sample
– Parent or sibling

95. Cryogenic Grinding- DNA Extraction

97. ANTE-MORTEM PAP SMEAR POST-MORTEM TEETH
DNA PROFILE COMPARISON

98. Other Lab Investigations

99. Scanning Electron Microscopy
• The fragment of hard material
found in the depths of a
human bite mark consists of
typical tooth enamel prisms,
indicating that suspects with
intact anterior teeth could not
have been involved in the
biting episode

100. Incremental Growth Patterns
• Associated with minor
changes in physiological
activity during the laying
down of the hard tissues of
the tooth and are said to be
unique to each individual

101. Drugs
• Tetracycline causes
discoloration of the
developing teeth by binding to
the hydroxyapatite crystals
• Fluorescent in ultraviolet light
• At least five independent
courses of treatment can be
seen as fluorescent lines in the
dentine
• the period of time elapsed
between the individual
courses of treatment can be
estimated

102. Analysis of body fluids
• Phosphoglucomutase (PGM)
enzymes may be extracted from
small fragments of dentine up to
some months after death and can
be typed using electrophoresis
• Two different types of enzymes (1
and 2) are indicated by the
stained bands and a PGM
grouping which is different from
that of a suspect will eliminate
him or her from the enquiry

103. Cheiloscopy PRINTS
103

104. Lip Prints
• Tsuchihashi named wrinkles and grooves visible
on lips as 'sulci labiorum rubrorum’
• Imprint produced by these grooves termed 'lip
print’
• Examination - 'cheiloscopy'
• Grooves are heritable & are supposed be
individualistic
• Therefore, can constitute material evidence left at a
crime scene

105. 105

106. RUGOSCOPY

107. Palatal Rugae
• Rugae Pattern Unique to an Individual
• Do not change shape with age and reappear
after trauma or surgical procedures

108. Facial Reconstruction
• Obtain Skull
• Determine demographic
information
– (female, Caucasian, early 40s)
• Note unique features
– (had lost all back teeth on
upper and lower jaw)
• Anything known about this
individual?
– (came to U.S. by boat in 1710
from Europe, died and buried
in NY around 1733)

109. Facial Reconstruction…
• Add Tissue depth
Markers
– Based largely on sex and
race
• Begin to add common
fat deposits and
underlying muscles

110. Add muscle to average
depth for race
Add skin, nose, ears
Add features related to age and race
(wrinkles, eye and hair color)
Facial Reconstruction…

111. 7. Add clothing etc appropriate for the
time period, religious affiliations, etc
Facial Reconstruction…

112. MASS
DISASTERS

116. Information Technology
• Commonly used computer programs are:
– The FBI-NCIC program based on the California Dental
Identification system.
– CAPMI (Computer Assisted Postmortem Identification)
developed by US Army Institute of Dental Research.
116

117. Anti-Missile Technology
• May be able to help in identifying dead bodies
• Software was developed in Mexico, which recognizes the unique
characteristics of a person's skull when applied to common x-rays
• A computer working for the federal government was designing a
computerized means to photograph incoming missiles at one thousand
frames per second and identify them by specific characteristics within a split
second
• Bourgeois realized that this same technology could be used to find skull
landmarks on X-ray films taken of the head
• These lateral head films exist for “hundreds of thousands of individuals” who
have had dental surgery or orthodontics
• This new technique, with a good database, could have wonderful potential for
the world of forensic

118. MASS DISASTER
VICTIMS BODY PARTS VICTIMS RELATIVES BLOOD
DNAANALYSIS DNAANALYSIS
DNA PROFILE DNA PROFILE
ALLELES ALLELES
BA
Alleles A and B same - body identified
Alleles A and B different – body not identified
DNA Profile in Mass Disaster

119. Conclusion
• Forensic dentistry is still in its infancy and may be considered more
of an art or craft than a science
• It is important that for the development of forensic dentistry,
practitioners retain a healthy degree of scepticism of their abilities
• Proper records have to be maintained There is no more important
lay audience than the jurors in a murder trial, and they must not be
given the impression that the forensic dentist is a Sherlock Holmes
or a Hercule Poirot

120. ?QUESTIONS?