Forensic odontology

CONTENTS
• Introduction
• Uniqueness of human dentition
Definition
• Role of forensic science
• Fields of activity of forensic odontology
• History of forensic odontology
• The need for identification of human remains
• Techniques of human identification
• Comparative identification
• Mass disaster identification
• Reconstructive/dental profiling
• Identification of ethnic origin
• Sex determination
• Age estimation
• Criminal investigation

INTRODUCTION
• Forensic odontology, or forensic dentistry, is one of the most
unexplored and intriguing branches of forensic sciences.
• It primarily deals with identification based on recognition of unique
features present in an individual’s dental structures.
• Human dentition are Hard tissue analogue to finger prints.
• Teeth are resistant to postmortem destruction and are one of the
most durable parts of our body.
• Forensic dentistry plays a major role in identification in man made
or natural disasters-events that may not be identifiable through
conventional methods such as visual recognition or even finger prints.

1000 C
4000 C
2000 C
TEETH ARE EXTREMELY DURABLE EVEN AT HIGH
TEMPERATURE AND MAY BE IDENTIFIED EVEN WHEN THE
REST OF THE BODY HAS UNDERGONE DECOMPOSITION

WHAT MAKES THE TEETH UNIQUE?
• Essential characteristics of the human dentition which
provide them a certain uniqueness:
a) Intermixing of genetic racial characteristics that have upset
the natural balance between the jaw bones.
b) Chemical and structural modifications
resulting from disease processes.

c) Dental treatment itself is the single biggest contributor to
uniqueness of the dentition.
d) Teeth are the most indestructible part of the body and exhibit the
least turnover of the natural structure.
Fellingham and coworkers have calculated that there 1.8*10 19
possible combinations of 32 teeth being intact ,decayed ,missing or
restored.
DENTAL IDENTITY defined by Acharya and Taylor as “total of all
characteristics of the teeth and their associated structures which, while
not individually unique when considered together provide a unique
totality”

According to Webster’s dictionary:
Forensic means of, pertaining to, or appropriate
for the court of justice or public debate
• Forensic derived from the Latin word "forensics"
meaning public.

• Forensic science refers to the area of
endeavor that can be used in a judicial
setting and which is accepted by the court
and the general scientific community to
separate the truth from untruth.
• Forensic odontology is a branch of forensic
science.

Definition:
Forensic odontology is defined as “a
branch of dentistry which deals with the
proper handling and examination of dental
evidence and with the proper evaluation and
presentation of dental findings in the interest
of the dentist”.
-Keiser-Nielsen (1970)

ROLE OF THE FORENSIC SCIENCES:
• EXPERTS OF FORENSIC SCIENCES CAN BE SEPARATED INTO THE
FOLLOWING TEN CATEGORIES:
• 1.)CRIMINALISTICS
• 2.)FORENSIC ANTHROPOLOGY
• 3.)FORENSIC PATHOLOGY /BIOLOGY
• 4.)FORENSIC PSYCHIATRY
• 5.)FORENSIC ODONTOLOGY
• 6.)FORENSIC TOXICOLOGY
• 7.)QUESTIONED DOCUMENTS
• 8.)GENERAL
• 9.)JURISPRUDENCE
• 10.)ENGINEERING

FORENSIC ODONTOLOGIST DELVE INTO :
 Identifying unknown human remains through comparison of
postmortem dental evidence with dental records of the
presumed deceased.
 Assisting at the scene of a mass disaster and in the victims
identification.
 Eliciting the ethnicity/population affinity.
 Assessing the sex of the skeletonized remains.
 Age estimation
 Analysis and identification of bite mark.
 Presenting evidence in court as expert witness.

Fields of activity of forensic odontology:
(by “Cameroon & Sims”)
Major
fields
civil
criminal
research

• Civil class: (non criminal)
• It includes malpractice and other aspects of fraud and
neglect in which compensation is sought. Identification of
dead and living persons also comes under this category.
• Identification of victims of mass disaster.
• Craniofacial superimposition for indentification.

• Criminal sector
• It includes identification which is done by teeth and from
bite marks that may be present on the victim, assailant or
on some inanimate objects like food items.
• Research field
• It encompasses academic courses for undergraduate and
postgraduate training, teaching forensic odontology to
police and new research works.

HISTORICAL PERSPECTIVE OF FORENSIC
ODONTOLOGY
• Forensic odontology is probably as old as mankind
itself when according to the old testament THE
BIBLE says Adam was convinced by Eve to put a
'bite mark' in an apple.
• Apart from this, there are other major landmarks, from
identification of unknown bodies to solving crime cases,
which have resulted in the evolution of this Field.

• It is said that the first dental
identification
was made around 49 AD.
• When Agrippina, the jealous wife of
Roman Emperor Claudius ,demanded
the disembodied head of her husband’s
mistress, Lollia Paulina.
• Malocclusion served to confirm
her identity.
17

• In 66 AD an alternative story credits Sabina,
Nero’s mistress, as the victorious forensic
odontologist who examined the severed head of
Nero’s wife by her
characteristic black anterior tooth.
18

• Folklore also ascribes the first use of bite-mark
identification to King William the conqueror,
around 1066 A.D., whose habit was to secure his
mail with sealing wax imprinted with his bite.
• His anterior teeth were malaligned, thus allowing
verification of authenticity of his documents.
19

• 1199 AD –In India first case reported was of
Rathore Raja Jaichand of Kannauj, who was
recognised by his false anterior teeth after he was
killed in a battle.
20

• 1776 AD -First dental identification by Dentist
Dr.Paul Revere, identified his friend and patient,
Dr. Joseph Warren, who was killed in the
battle of Bunker Hill from the silver wire
fixed bridge he had made for him.
21

• Dr. Oscar Amoedo, who was Professor at a
dental school in Paris is considered as
"Father of Forensic Odontology".
• He presented a paper entitled "The role of
dentists in identification of victims of the
catastrophe of the Bazar de la Charite,
Paris, 4th May 1897", at the International
Medical Congress of Moscow.
• "L'Art Dentaire en medicine Legale"
was published in 1898. This was the first
book on forensic odontology.

• Dental evidence played a vital role in
identification of Adolf Hitler, during May 1945.
• During the war badly burnt bodies were found in
the bunker and one of them was Hitler’s.
• Kathe Echtmann, identified Hitler by the dental
bridge he had constructed in Hitler's lower jaw.
• His dental findings were tallied with antemortem
dental records and radiographs thus solving the
problem.

ADOLF HITLER
Identified by: Kathe Echtmann

• Dentition was an important lead in the
identification of remains of various leaders, who
were killed, like Zia Ul Haq, former Pakistani
President and Rajiv Gandhi, former Indian
Prime Minister.
• Forensic Odontology was also useful in
identification of numerous deceased people after
destruction of World Trade Centre in September
11, 2001.

• In the 20th century, Forensic Odontology was practically
considered a part and parcel of forensic medicine.
• First formal instructional programme in forensic dentistry
was given in United States at the Armed Forces Institute of
Pathology.
• FDI in 1965 recommended to include forensic odontology in
the curriculum of teaching institutions.

• In the last few decades, the basic pattern of forensic odontology
has changed due to the advances in dental materials and
laboratory techniques, with improvements in scientific and
photographic technology making it much nearer to forensic
sciences.

Reasons for identification of humans:
• Criminal – Typically an investigation to a crime
death cannot begin until the victim has been
positively identified.
• Marriage – Individuals from many religious
backgrounds cannot remarry unless their partners
are confirmed deceased.
• Monetary : The payment of pension, life insurance
and other benefits relies upon positive confirmation
of death.

• Burial : Many religions require that a positive
identification be made prior to burial in geographical
sites.
• Social : Society's duty to preserve human rights and
dignify beyond life begins with the basic premise of
an identity.
• Closure : The identification of individuals missing for
prolonged periods can bring sorrowful relief to family
members.

Overview
FORENSIC DENTISTRY
Human identification Bite mark analysis
Comparative
identification
Postmortem
dental profiling
Dental records Forensic anthropology
Age
Race
Sex

DENTAL IDENTIFICATION
PROCEDURES
THERE ARE TWO FORMS OF DENTAL
IDENTIFICATION:
Comparative identification
Reconstructive identification

COMPARATIVE IDENTIFICATION
• Establish if deceased
remains and antemortem
records represent same
individual
• Compare postmortem
dental remains with
antemortem dental records
(written notes, casts,
radiographs)
POSTMORTEM DENTAL PROFILING
• Antemortem dental records
are unavailable
• No clues as to the
identification of the
deceased
• Compile a postmortem
dental profile

• Comparative identification attempts conclusive
identification by comparing the dead individual’s teeth with
presumed dental records of the individual.
• Reconstructive identification or dental profiling attempts to
elicit the ethnicity or ‘race’ gender, age, and occupation of
the dead individual

COMPARATIVE DENTAL IDENTIFICATION
Oral autopsy
Obtaining dental records
Comparing post and ante-mortem dental
data
Writing a report and drawing conclusions
It is the conventional method of post-mortem dental identification, and includes
4 steps:

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ORAL AUTOPSY
• Autopsy Dissection to expose the organs
Determine the cause of death
• The forensic dentist should be aware about common findings like rigor
mortis which may render the jaws rigid so the use of mouth gags,
trismus screws or intraoral myotomy may be useful for jaw
separation.
Also known as necropsy or post mortem .
Critical examination of the external features of the body such as gender, ethnicity
,built, wounds, scars, tattoos and body piercing are done.

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• Teeth may need to be reinforced with cyanoacrylate glue prior
to examination in cases of incinerated remains as they become
brittle.
• A thorough investigation of the soft tissue injuries, fractures,
and presence of foreign bodies should be undertaken.
• All information should be entered onto the standard ‘Interpol
post-mortem form’, which is color-coded in pink.

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OBTAINING DENTAL RECORDS
• Antemortem data constitutes the information of dental treatment
undergone and dental status of a person during his/her lifetime.
• Dental records should be obtained which may be in the form of :
- Information of treatment and dental status
- Dental charts
- Radiographs
- Casts/Photographs
• Contents should be transcribed into standard ‘Interpol ante-mortem
form’, which is color-coded in yellow.

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COMPARING POST AND ANTEMORTEM DENTAL
DATA
• Following postmortem examination and transcription of
antemortem data, the odontograms are compared.
• Features to be evaluated include
- Tooth morphology and associated bony structures
- Any pathology
- Dental restorations
- Any extraordinary dental characteristics
- A single point concordance between post and antemortem
data may be sufficient to establish identity ,considering of
course , the uniqueness of such a feature and circumstances of
the case.

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WRITING A REPORT AND DRAWING CONCLUSIONS
• A detailed report and factual conclusions, based on the
comparison, must be clearly stated.
• The report should include an explanation for any
inconsistencies that were observed for the purpose of clarity

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• Acharya and Taylor have suggested a range of
conclusions that may be obtained:
a) Positive identification: Comparable items are sufficiently
distinct in the ante-mortem and postmortem databases; no
major differences are observed.

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b) Possible identification: the data is consistent but the lack
of quality ante mortem or post mortem information means
one cannot confirm identity.
There is a high level of concordance between the data but,
usually with no radiographic support.

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c)Insufficient evidence:
Available information is insufficient to form the basis for a
conclusion.

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d) Exclusion: Unexplainable discrepancies exist among
comparable items in the ante-mortem and postmortem
databases. The data contains differences that indicate a
mismatch.

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IDENTIFICATION IN DISASTERS
• Mass disaster is an emergency situation in which the need
regarding the response is greater than the resource available.
• A “mass fatality incident "is an occurrence that causes loss of life
that exceeds death investigation resources in a community.
• Disasters require identification of the post mortem remains.
• During disasters there are jurisdictional and political issues also
that need to be addressed.
• According to Clark almost 50% of the identifications in disasters are
by dental means.

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• The world has experienced a plethora of mass disasters in recent
years - hurricanes, earthquakes, floods, volcanic eruptions,
terrorist acts and armed conflicts in addition to the naturally
occurring disasters.

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• First mass disaster where dentistry played a role in identifying
victims was in the year 1897, "Bazar de La charite fire" accident in
Paris.
• Since then numerous reports are available stating the vital role played
by dentist in mass disaster.

DISASTER MANAGEMENT: ROLE OF DENTAL PROFESSIONALS
• Terrorist attacks and other catastrophic events are likely to create
demands that far exceed the capacity of the medical and public
health systems to respond.
• Although dentists comprise an important aspect of health team, their
role or utility has not been emphasized.
• DENTAL PROFESSIONALS AND RESPONSE
• Dentists along with other health professionals can act as first
responders and bring well-honed skills to an emergency.

DENTAL PROFESSIONALS CAN PROVE TO BE HELPFUL DURING A
MAJOR PUBLIC HEALTH DISASTER IN THE FOLLOWING WAYS:
1. SUPPORTING OTHER HEALTH PROFESSIONALS :
• When the local medical resources are unable to cope
adequately with huge number of victims, dentist can be
recruited to provide certain services that will allow physicians
to do things only they can do. Dentists can enhance the surge
capacity of the local medical system until additional
physicians arrive or demand for immediate care decreases.
2.DENTAL OFFICES ACTING AS MEDICAL SITES :
• Dental offices are equipped with potentially useful equipment
and supplies and should be prepared to serve as decentralized
auxiliary hospitals in case the need arises.

3. DENTAL SURVEILLANCE :
• Dentists can contribute to bioterrorism surveillance by
being alert to clues that might indicate a bioterrorist
attack.
• Since dentists are scattered throughout a community
they can be a part of effective surveillance network with
their eyes and ears open to information on unusual
syndromes in the community as well as unusual clinical
presentations.
• 4.FORENSIC ASSISTANCE :
• Forensic odontology continues to be a crucial element in
nearly all mass disasters whether natural, accidental, or
intentional. Dental identifications have always played a
key role in victim identification during natural and
manmade disaster situations and in particular mass
casualties normally associated with aviation disasters

• 5.TRIAGE SERVICES:
• Triage must be done to prioritize treatment among casualties .
• Dental offices could serve as triage centers if needed.
• TRIAGE: means sort out
• It can be applied to various situations including emergency
department patients to large scale disasters.
• It is a way of categorizing patients in the order of their injuries and to
make the most efficient use of the available resources.
• Most common system is (NATO) North Atlantic treaty organization
system of triage.

TRAIGE CATEGORIES IN NATO SYSTEM
T1 IMMEDIATE Rapid intervention to save
life
T2 DELAYED Intervention within hours
required
T3 MINOR Intervention required but
condition unlikely to
survive.
T4 EXPECTANT Survival unlikely due to
extent of illness or injury.
NATIONAL DISASTER LIFE SUPPORT PROGRAM in US teaches a simplified
triage system called MASS TRIAGE: move ,assess, sort and send.

• Triage system involves a color-coding scheme
using red, yellow, green, white, and black tags:
• Red tags - (immediate) are used to label those
who cannot survive without immediate
treatment but who have a chance of survival.
• Yellow tags - (observation) for those who
require observation (and possible later re-
triage). Their condition is stable for the moment
and, they are not in immediate danger of death.
These victims will still need hospital care and
would be treated immediately under normal
circumstances.
• Green tags - (wait) are reserved for the "walking
wounded" who will need medical care at some
point, after more critical injuries have been
treated.
• White tags - (dismiss) are given to those with
minor injuries for whom a doctor's care is not
required.
• Black tags - (expectant) are used for the
deceased and for those whose injuries are so
extensive that they will not be able to survive
given the care that is available.

6. DEFINITIVE TREATMENT :
• Dental professionals along with other health care personnel
may be able to provide treatment to the people during any
disaster event.
• Dentists have training and experienced in many areas that
may be a part of casualty care in mass casualty events. Oral
and maxillofacial (OMS) practitioners are qualified trauma
surgeons who can provide first aid.
• For this reason, it is advocated that civilian dentists should
be trained along with dental personnel in armed services in
augmenting and teaming with their medical counterparts .

7.DISTRIBUTION OF MEDICATION
• In mass casualty situations, particularly after a bioterrorism attack or
the unfolding of a pandemic infection, the population may
require medication.
• Dentists can be called on to prescribe and dispense the
medications required after the determination has been
made by the physician and public health officials managing
the disease outbreak.

• 8. IMMUNIZATION
• To limit the spread of infectious agents, whether from
a natural pandemic, a deliberate bioterrorism attack,
or contamination as a result of a local event, rapid
immunization of great numbers of individual may be
required in a short amount of time.
• In major metropolitan areas, where the spread of
communicable disease is facilitated, physicians and
nurses may be unable to implement such a program
in critical time frame required.
• Dentists can participate in mass immunization
programs with minimum of additional training and
may be critical factor in the success of urgent
programs.

• Medical Reserve Corps are community based units.
• Their main function is to organize and utilize volunteers who want to
donate their time and expertise to promote healthy living throughout
the year and to prepare for and respond to emergencies.
• MRC volunteers include medical and public health professionals such
as physicians, nurses, pharmacists, dentists, dental hygienists,
veterinarians, and epidemiologists.
• Most MRC units are coordinated through the Emergency
Preparedness Department and coordinate their preparedness efforts
with public health officials.
• MRC volunteers can assist during emergencies as well as non-
emergent public initiatives and ongoing community health outreach
and education efforts.
• The MRC is a definitive and formal opportunity for dental
professionals to serve their communities

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• The Interpol's disaster victim identification guide as
well as Vale and Noguchi, suggest the division of the
dental section into three subsections-
a) Post-mortem unit
b) Ante-mortem unit
c) Dental comparison and identification unit

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POST-MORTEM UNIT
• It is useful if Forensic dentists are part of
the search and recovery team at the site of disaster.
• Preliminary examination of the mouth is made at the site and definitive
examination is done at the temporary mortuary set up.
• A portable dental radiography apparatus should be installed at a convenient
area within the temporary mortuary.
• Teeth and jaw specimens also may be removed from a body for examination

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ANTE-MORTEM UNIT
• Personnel in this unit should be capable of reading and
interpreting all dental records provided.
• The quality, quantity and variety of dental records present a
major obstacle to this unit.

63
DENTAL COMPARISON AND
IDENTIFICATION UNIT
• This subsection handles comparison and confirmation of
identification.
• Vale and Noguchi approve the commencement of comparison
and identification once all postmortem data is available.
• Computer software programs have
been developed to simplify comparison like IDENTIFY,
ODONTID, IDIS etc

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IDENTIFICATION FROM DENTAL DNA
• The conventional methods require one basic element that may
not be available readily- adequate and complete dental records.
• Pretty and Sweet have stated that as teeth can resist extreme
conditions, they are an excellent source of DNA.

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• Polymerase chain reaction (PCR) is a
routinely applied forensic investigation,
which allows amplification of even highly
degraded DNA.
• A major advantage is that the DNA
pattern may be compared to a parent or
sibling, thus allowing identification.

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Types of DNA
• Nuclear DNA is used commonly in forensic cases but
mitochondrial DNA can substitute in cases where nuclear
DNA is unavailable.
Nuclear DNA Mitochondrial DNA

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• Extraction of Dental DNA:
• Pulpal tissue is considered to be the best source of dental DNA
due to its neurovascular nature.
• Sweet and Hildebrand advocated cryogenic grinding for
extracting DNA.
• Thus DNA may be obtained from intact, carious as well as
root filled teeth.

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• Trivedi and coworkers have suggested a less destructive
method for DNA isolation, which involves drilling of the root
canals, scrapping the pulp area and subsequent flushing of the
tissue debris, thus retaining the morphology of the tooth.

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PALATAL RUGAE IN IDENTIFICATION
• In edentulous individuals a useful method of identification is
by examining the palatal rugae pattern.
• Rugae pattern like teeth are considered unique for an
individual.
• Palatal rugae are well protected in incidents
of fire and high impact trauma.

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ANALYSIS OF RUGAE PATTERNS
• Rugae patterns may be superimposed on photographs of plaster
models.
• Limson and Julian have recently developed a software program,
‘RUGFP-IP Match’.
• In this digitized images of the palate, characteristic points are
plotted which are then processed by a software and the
information sequentially stored corresponding to pixel position.

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DENTAL PROFILING
• When ante-mortem information is available, it is possible to
pinpoint the identity of the dead.
 Circumstantial evidence inadequate
 Dental records are not traceable
 This can be used in case of skeletal remains in an isolated areas
with no proof of identification.
Dental profile

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• Dental profiling includes extracting a triad of information-
a) Ethnic origin
b) Gender
c) Age
• The information from this process will enable a more focused
search for ante-mortem records.

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IDENTIFYING ETHNIC ORIGIN FROM TEETH
• The diversity of human species is mainly as a result of genetic
influences, as well as environmental factors.
• Human diversity permeates to dental morphology as well, and as a
result it is possible to identify an individual’s ethnic origin based
purely on one’s dentition.
• Human races have been divided in to four i.e CAUCASOID,
MONGOLOID NEGROID, AND AUSTRALOID

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GENETIC AND ENVIRONMENTAL
INFLUENCES ON TEETH
• Different populations show considerable diversity in their
dentition and several features have been grouped accordingly.
• For population identification, those dental features that have a
strong genetic and weak environmental influence are useful.

• Dental features have complex mode of
inheritance
• They are combination of hereditary and
environmental factors to which a person is
exposed

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Dental features
Metric (tooth
size)
Non-metric (tooth
shape)• Based on measurements
• Influenced by environmental
factors
• Based on presence of a
particular feature.
• Are more heritable and
dependable

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• The range of dental variation among humans is great and
many features have to be considered before concluding on
ethnic or population origin.
• The high and low frequency of occurrence of a given nonmetric
feature are important in identifying a particular
population/ethnic group.

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• Morphological variations in the teeth that vary with ethnic
groups include:
- Shovelling
- Carabelli’s feature
- Cusp six and cusp seven
- Accessory ridges on canine
- Arrangement of groove patterns of molars
- Protostylid

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SEX DIFFERENTIATION
• Determining the sex of unknown human remains is the
second step in the triad of building a dental profile.
• Sex can be determined based on data from
a) Morphology of skull and mandible
b) Metric features
c) DNA analyses of teeth

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SEXING FROM CRANIOFACIAL
MORPHOLOGY AND DIMENSIONS
• The use of morphological features is a common approach but is
not reliable until well after puberty.
• Since no single feature is characteristic, use of multiple
features tends to be more accurate.
• As they are affected by old age changes, application of sexing
needs to be confined to young adults and the middle aged.

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• It has been noted by many researchers that morphological
features are subjective, and can result in errors when used by
an inexperienced observer.
• Thus sexing should be based on measurement of the skull
using lateral cephalometric tracings and involves rigorous
training in osteology and measurement techniques.

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SLNO. FEATURES MALE FEMALE
1. Architecture Rugged Smooth
2. Frontal eminence Small Large
3. Forehead Sloping Vertical
4. Supraorbital ridges Well developed Poorly developed
5. Glabella Prominent curve Relatively flat
6. Orbits Squarish Rounded
7. Mastoid process Large Small
8. Digastric fossa Broad Narrow
9. Palate V-shaped Parabolic
10. Mandible Larger, thicker,
broader
Smaller, thinner,
narrower

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SEX DIFFERENCES IN TOOTH SIZE
• Teeth may be used for differentiating sex by measuring their
mesiodistal and buccolingual dimensions.
• Studies have shown significant differences between male and
female permanent and deciduous tooth crown dimensions but
they are population specific and do not apply to the world at
large.

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• DENTAL INDEX:
• Tooth proportions also have been suggested for differentiating
the sexes.
• The lateral incisors are distinctly smaller than the central
incisors in females.

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• MANDIBULAR CANINES ARE FOUND TO EXHIBIT THE GREATEST SEXUAL DIMORPHISM
AMONGST ALL TEETH. “Sexual dimorphism” refers to those differences in size, stature, and
appearance between male and female that can be applied to dental identification because
no two mouths are alike.
• It was for these reasons that Rao et al. proposed the exclusive use of mandibular canines in
sex identification. The authors developed an index, which they named mandibular canine
index (MCI)
• …
• The standard MCI value is used as a cut- off point to differentiate males from females.
• standard value is 0.274 if it is less than equal to mci it is female if the
value is more it is male.

• In addition to the canines being the most sexually
dimorphic teeth in terms of size, Scott and Turner
highlight that the ‘Distal Accessory Ridge’, on the
canine is the most sexually dimorphic trait in the
human dentition, with males showing a
significantly higher frequency compared to the
females.

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SEX DETERMINATION BY DNA ANALYSIS
• Forensic DNA analysis for sex determination has been shown
to produce highly accurate results.
• The AMEL gene coding for a highly conserved protein,
amelogenin, differ in the intronic sequence of the alleles.
• Thus the females (XX) have two identical AMEL genes but the
males (XY) have two nonidentical genes.

SCHRANTZ AND BARTHA (1963) proposed seven
steps for sex determintion.The results are as
follows:
• Bucco – Lingual diameters of teeth are smaller in
females than males.
• Mesio-Distal diameters of Upper central incisors is
larger than upper canine in females, while they are
equal in males
• Differences of Mesio-Distal diameter of upper
central incisor and upper lateral is about 2.1mm in
females, and 1.8 in males
90

• Differences of Mesio-Distal diameter of lower
canine and lower lateral incisor is smaller in
females (0.7mm versus 1.8mm in males)
• Fusion of second mandibular molar root is more
frequent in females
• Frequency of hypoplasia and agenesis of third
molars is higher in females
• The phenomenon of hyperdontia is more frequent
in males
91

AGE ESTIMATION
92
FINAL STEP OF DENTAL PROFILING

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DENTAL AGE ESTIMATION
• The final step in the triad of dental profiling, is age estimation
which is an important subspecialty.
• Dental age is one of the few measures of physiologic
development that is uniformly applicable.
• Dental age estimation makes use of morphologic, radiographic,
histological, and biochemical methods to examine age
dependant changes in teeth.

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Age estimation in prenatal and early postnatal child
• Histologic techniques may be used for observing tooth
mineralization upto 12 weeks before it is actually apparent on
radiographs.
• Estimating the age in this age group may have legal
implications in cases that involve feticide and infanticide.

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• The presence of neonatal line indicates live birth and
it is possible to estimate the exact period of survival of
the infant in days by measuring the amount of
postnatal hard tissue formation, and thus can be an
evidence to the brutal act of infanticide.
• According to Ciapparelli, the neonatal line may take
upto three weeks after birth to form.
• Hence a false result may be produced when one
concludes that the absence of the neonatal line proves
that the individual was ‘stillborn’.

• Stack suggested alternative method to measure
the Dry weight of the mineralised tooth.
The developing teeth in a child at
 6 months IU weight about 60 mg
In newborn about 0.5 g
6 months after birth weigh about 1.8 g
97

Age estimation in children & adolescents
CHILDREN AND
ADOLESCENTS
ERUPTION
SEQUENCE
TOOTH
CALCIFICATION
98
Estimation of age by tooth emergence is a convenient clinical method.
The emergence of deciduous teeth is under genetic control and is relatively
regular but in permanent teeth influence of intraoral environment is greater

8/30/2018 100
• Evaluation of radiographs to assess tooth
calcification is a much better alternative, since:
a) Calcification of teeth can be observed from radiographs for a period of
several years
b) It is not altered by local factors such as lack of space, infections etc.
c) It also allows assessment of age at periods when no emergence takes
place.

8/30/2018 101
SCHOUR AND MASSLER’S METHOD
• The chart or atlas was probably the first attempt at
scientific dental age estimation.
• They describe 20 chronological stages of tooth
development starting from 4 months IU until
21years of age.
• The chart is based on histological sections
which permit direct comparisons
with radiographs.

8/30/2018 102
DEMIRJIAN’S METHOD
THIS MAKES USE OF A SCORING SYSTEM IN WHICH
THE DEVELOPMENT OF THE TEETH IS DIVIDED INTO
EIGHT STAGES.
Development of Left side seven mandibular teeth
were divided into 10 stages (0 to 9)/(0 and A to H )
Each tooth is assigned a “ maturity score” ,maturity
score for each tooth is added and a total maturity
score obtained
Then total maturity score of all teeth is plotted on a
chronologic age conversion table.
Maturity score and age conversion table are separate
for both sexes.

Demirjian’s chart
103
STAGE E indicates crown completion
STAGE H indicates completion of tooth
calcification

Hegde R. J,Sood P.B.Dental Maturity as an indicator of chronological age :
Radiographic evaluation of Dental age in 6 to 13 years children of Belgaum using
Demirjian Methods. J Indian Sot Pedo Prev Dent December (2002) 20 (4) : 132-138
• The study was designed to determine dental age
from orthopantomograph using Demirjian
• The sample for the study consisted of 197subjects
between 6-13 years of age .
• Using demirjian method, mean difference
between true and assessed age for males showed
overestimation of 0.14 years (51 days ) and
females showed overestimation of 0.04 years
• (15days).
• Demirjian method showed high accuracy when
applied to Belgaum children .

8/30/2018 105
THIRD MOLARS IN AGE ESTIMATION
• Although the third molar is a valuable indicator of age in the
age group of 16-23 years, accuracy in age estimation using
third molars is questionable.
• Gunst and associates concluded that the age of the individual
can be reliably estimated using specific formulae.

8/30/2018 106
• Gunst found that when all the third molars have completely
calcified, the chance of the individual being 18years old is 96.3
percent and 95.1 percent for males and females respectively.

AGE ESTIMATION IN ADULTS
It’s challenging when compared to young age
groups as numerous endogenous
and exogenous factors,
such as disease, nutrition and
physical strain play a role.
107

8/30/2018 108
Gustafson’s method
• Gosta Gustafson in 1950 developed a method based on the
histological and morphological changes of the teeth
1) Amount of occlusal attrition (A)
2) Loss of periodontal attachment (P)
3) Deposition of secondary dentin (S)
4) Cemental apposition at the root apex (C)
5) Root resorption at the apex (R)
6) Dentine translucency (T)

8/30/2018 109
• For each of these regressive changes or variables, different
scores ranging from 0-3 are assigned and adding the allotted
score for each variable, a total score is obtained (X).
• Age= 11.43+4.56X
• Maples and Rice proposed a correction and put the formula as
• Age=13.45+4.26X

8/30/2018 110
• Johanson proposed seven grades instead of the original four and
suggested the formula as
• Age = 11.02+(5.14A)+(2.3S)+(4.14P)+(3.71C)+(5.57R)+(8.98T)
• Pillai and bhaskar obtained only 50% success in estimating age when
this method was applied on an Indian population.

8/30/2018 111
• Limitations of Gustafson's method:
 None of the variables could be used alone except dentine
translucency.
 Training in histological techniques is essential.
 Equipment such as stereomicroscope is required.
 When only one tooth is used the age range increased.
 Age range also increased in teeth over 50years old.

8/30/2018 112
DENTINE TRANSLUCENCY
• Bang and Ramm reported a significant increase in root
translucency with age due to a decrease in the diameter of
dentinal tubules caused by intratubular calcification.
• Root dentin starts to become translucent during the 3rd decade of
life beginning at the apex and advancing coronally
• For age estimation, Solheim suggested that the translucency length
or area may be measured, though length had a greater correlation.

8/30/2018 113
• Disadvantages include:
 Irregular junction of translucent or non-translucent zones
making it difficult to measure length.
 Underestimation of age in older adults, due to slowing down
of dentinal sclerosis.

8/30/2018 114
AGE ESTIMATION FROM INCREMENTAL LINES OF
CEMENTUM
• Karger and grupe made use of mineralized unstained cross-
sections of teeth and estimated from acellular cementum
incremental lines.
• An accuracy of 2-3years within the chronological age has been
reported.

The cementum incremental lines
under light microscope
The cementum incremental lines under
polarized microscope
The area selected for counting (middle
third of root cementum)
Research microscope with
photomicrographic attachment
and computer setup with image analysis
software

8/30/2018 116
• Disadvantages include:
 Pathological state of periodontium may compromise the
precision of ageing.
 There is a need to extract and section the teeth. So, it is not
practical among living adults.

8/30/2018 117
AMINO ACID RACEMIZATION
• Helfman and Bada first suggested a relationship between
dentinal age and the extent of aspartic acid racemization in
dentine.
• There is a 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.

8/30/2018 118
• D-L ratio can be measured in those proteins that are
synthesized early in life and are not replaced, such as in brain,
lens, bone and teeth.
• Waite and colleagues considered this method to be very
accurate with age estimates within three years of actual age

KASAB….
• The court trying Ajmal Kasab in Arthur Road Jail for
the 26/11 case had ordered an inquiry to determine his
age before announcing his Death sentence to prove
that he is not a Juvenile
• An ossification test to determine bone density, and a
dental X-ray to check his wisdom tooth were done.
119

CRIMINAL INVESTIGATION
BITE MARKS
 LIP PRINTS
 CHILD ABUSE & NEGLECT

DEFINITION:
“ A mark made by the teeth, either alone or in combination with other mouth
parts”. - McDonald (1974)
Biting is a primitive type of assualt and results when teeth are
employed as a weapon in an act of dominance or desperation

Foundation of bite mark analysis :
- Each individual’s dentition is presumed to be
unique.
- This presumed uniqueness is accurately recorded
in the characteristic of the injury on the skin or
object

Webster, 1982 classified bites on inanimate
objects as follows :-
• Type 1 – Fractures with limited
tooth penetration (chocolate).
• Type 2 – Fractures with considerable
tooth pressure (apples).
• Type 3 – Fractures with complete
penetration extending through
the food substance with
slide marks (thin cheese).
123

Mac Donalds- etiologic
Macdonald DG. Bite Mark Recognition And Interpretation. J Forensic Sci Soc 1974; 14(3):
229
• Tooth pressure marks-tissue-direct application of
pressure by teeth. Eg- incisal/occlusal surfaces
• Tongue pressure marks- sufficient amount of tissue
in mouth-presses against rigid areas-lingual surface
of teeth & palatal rugae
-marks left on skin- Suckling
• Tooth scrape marks- scraping of teeth across bitten
material. caused by ant teeth, scratches &
superficial abrasion

Outlines of the same set of teeth. The
different perimeter shapes depend on how
far the teeth are pressed into the test
substrate.

Forensic aspects of bite marks can be
applied in the following circumstance
1. Teeth marks left in food stuffs
2.Teeth mark on criminals: when the victim
bites the assailant in self defense.
3.Teeth marks on victim: found in cases of
assault and murder. It may be due to
- Self inflection by the victim
- Criminal attacking the victim

8/30/2018 127
Bite mark appearance
• Type of injury
• Identifying the injury as a bite mark
 Gross features
 Class features
 Individual features
• Site of bite marks

Typical presentation of bitemark injuries
•Females are most often bitten on the breasts
and legs during sexual attacks,
•whereas bites on males are commonly seen on
the arms and shoulders.
•A representative human bite is described as an
elliptical or circular injury that records the
specific characteristics of the teeth

NOTE: - when intensity of bite is great, causes “Avulsion” (breaking of
integrity of skin surface) where part of tissue is bitten off
IDENTIFYING THE INJURY AS BITEMARK
Sweet suggested that human bite may be identified by following
features:-
1. GROSS FEATURES:
Circular or elliptical mark caused by upper &lower arches.
Central area of ecchymosis mark is seen because of suckling action or negative
pressure created by mouth.

3. INDIVIDUAL FEATURES:
These make bite marks distinct
Eg: fractures rotations etc.
2. CLASS FEATURES:
differentiate b/n tooth type
TEETH MARKS PRODUCED
Incisors Rectangular
Canines Triangular/rectangular
Premolars and molars Spherical/ pointed.

8/30/2018 132
BITE MARK INVESTIGATION
• Bite mark evidence collection from the victim:
• After the preliminary investigation, the primary concern is
patient care.
• The protocol for bite mark evidence collection includes the
following steps, as suggested by the American Board of
forensic odontology.

8/30/2018 133
• Visual examination
• Photography
• Orientation photography
• Close-up photography
• Saliva swab
• Impressions
• Evidence collection from the suspect

8/30/2018 134
BITE MARK ANALYSIS AND COMPARISON
• Proceed with the analysis by taking into consideration the
uncommon characteristics of the bite mark.
• The measurement of the mark constitutes the ‘metric analysis’
and may be obtained by vernier calipers or software programs.
• Metric analysis is done in conjunction with ‘pattern association’
which involves matching the pattern of bite injury to the
arrangement of teeth in the suspect.

VernierCalipers
METRIC ANALYSIS
Computer digitization method

PATTERN ASSOCIATION
BITE MARK PHOTOGRAPH FROM
VICTIM
COMPARISON
MODELS FROM SUSPECT

 Lip prints are used for personal identification.
 The imprint produced by the grooves on the lips is termed lip
prints.
 The examination of lip prints is known as CHEILOSCOPY.
 These grooves are heritable and are supposed to be
individualistic.

8/30/2018 138
• Santos classified lip prints as:
1. Simple wrinkles
 Straight line
 Curved line
 Angled line
 Sine – shaped line
2. Compound wrinkles
 Bifurcated
 Trifurcated
 Anomalous

8/30/2018
• Tsuchihashi divided the pattern of grooves into six types:
 Type I – Clear cut vertical grooves that run across the
entire lip.
 Type I’ – Similar to Type I, but does not cover the entire
groove.
 Type II – Branched grooves
 Type III – Intersected grooves
 Type IV – Reticular grooves
 Type V – Grooves that cannot be morphologically
differentiated.

LIP PRINTS
140
DISADVANTAGE
1.Trauma, pathosis, surgical treatment can affect the size and
shape of the lip
2.The zone of transition close to vermillion border is extremely
mobile so prints produced may differ depending on pressure
applied and its direction
The lips are divided into quadrants –a horizontal line dividing the upper and lower lip and a vertical
line dividing right and left sides.

8/30/2018 141
CHILD ABUSE
• Child abuse has been defined as ‘any act of commission or
omission that endangers or impairs a child’s physical or
emotional health and development.
• It may result in tearing of mucosa, frenum or avulsed or
fractured teeth or jaws.

Types of Child Abuse
• physical abuse
• sexual abuse
• emotional abuse
• neglect

Rates of harsh or moderate forms of physical punishment
(WHO) WORLD REPORT ON VIOLENCE AND HEALTH (2002)

Rates of verbal or psychological punishment
(WHO) WORLD REPORT ON VIOLENCE AND HEALTH (2002)

8/30/2018 145
• A characteristic feature is that abuse injuries are multiple and
repetitive in nature.
• The dentist should understand that his testimony may be
needed for legal proceedings.
• Attempting to provide advice or therapeutic counseling for
victims is beyond the scope of dentistry and it may result in
more harm than benefit.

PUBLIC HEALTH SIGNIFICANCE OF
FORENSIC ODONTOLOGY
• Community Dentistry has developed as the dental
profession's response to a social conscience, recognising
the individual social and health needs and personal
rights of each member of the community.
• In this context, forensic odontology is seen as providing
that body of dental expertise necessary for the
fulfillment of a number of social functions required by
law, in both the civil and criminal arenas, with
particular reference to the scientific identification of the
dead, the investigation of bitemarks, the estimation of
age and dental traumatology.

• The important role of dental records in these
matters emphasises the social responsibility of each
dentist to exercise great care in the documentation
of his treatment procedures.
• The social responsibility of dental educators to
include forensic odontology in the curricula of all
dental schools, particularly in developing countries,
is stressed.
• Research in forensic odontology should take into
account the particular needs of each community in
the light of their geographical, social and cultural
backgrounds.

8/30/2018 148
CONCLUSION
• Forensic dentistry in the last half century made giant strides
and has become a field of specialized study.
• Every citizen desires to live in a decent orderly society with
capable judiciary, and so each one of should help in the noble
cause of the ‘defense of the innocent and punishment of the
guilty’.

8/30/2018 149
• If the various investigating agencies are made aware of the
potential contribution of dental surgeon in identification, the
demand for forensic dentist is bound to increase.
• It is the public duty of the dentist to assist in problems
involving medicolegal identification of unknown body, and
dental evidence plays a vital role.

PHASES OF FORENSIC IDENTIFICATION:
Preliminary Evaluation:
•Nature of death
•Reason of dental input
Phase 1 Postmortem Exam:
•Facial & intraoral photograph
•Oral structures
•Radiographs
•Dental impressions
Phase 2 Data collection & ante-mortem investigation:
•All available dental records
•Original radiographs
•Dental models
•Cephalometric films
Phase 3 Comparison & conclusion:
•All postmortem & ante-mortem information
obtained & charted
•Results compared
•Conclusion reached
Phase 4

Procedure in dental identification:
Recovery of dental structures;
Reconstruction & examination;
Collection of ante-mortem records;
Transcription of dental records;
Comparison of odontograms;
Report

REFERENCES
1. ROTHWELL BR. PRINCIPLES OF DENTAL IDENTIFICATION DENT CLIN NORTH AM
2001; 45 (2): 253-270
2. TEXT BOOK OF FORENSIC ODONTOLOGY – PROMOD K DAYAL.
3. SHAFER, HINE, LEVY. SHAFER’S TEXTBOOK OF ORAL PATHOLOGY. 6TH
ED. NEW DELHI: ELSEVEIR; 2009. P-871-99.
4. TEXT BOOK OF OUTLINE OF FORENSIC DENTISTRY- JAMES A CATTONE,DDS
PRETTY IA. FORENSIC DENTISTRY:1.
5. IDENTIFICATION OF HUMAN REMAINS. DENT UPDATE 2007;34:621-
634
6. SINGH J ,GUPTA KD ETAL. SEX DETERMINATION USING CHEILOSCOPY AND
MANDIBULAR CANINE INDEX AS A TOOL IN FORENSIC DENTISTRY J FORENSIC
DENT SCI. 2012 JUL-DEC; 4(2): 70–74.

7.MESOTTEN K1, GUNST K, CARBONEZ A, WILLEMS G. DENTAL AGE ESTIMATION AND THIRD
MOLARS: A PRELIMINARY STUDY. FORENSIC SCI INT. 2002 SEP 26;129(2):110-5.
8.HEGDE R. J,SOOD P.B.DENTAL MATURITY AS AN INDICATOR OF CHRONOLOGICAL AGE :
RADIOGRAPHIC EVALUATION OF DENTAL AGE IN 6 TO 13 YEARS CHILDREN OF BELGAUM
USING DEMIRJIAN METHODS. J INDIAN SOT PEDO PREV DENT DECEMBER (2002) 20 (4) :
132-138
9.AGGARWAL P, SAXENA S, BANSAL P. INCREMENTAL LINES IN ROOT CEMENTUM OF
HUMAN TEETH: AN APPROACH TO THEIR ROLE IN AGE ESTIMATION USING
POLARIZING MICROSCOPY. INDIAN J DENT RES 2008;19:326-30.
10.GAMBHIR RS, KAPOOR D, SINGH G, SINGH G, SETIA S. DISASTER MANAGEMENT:
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12 FEB, 2013.
11..SWEET D, SHUTTER GG. ANALYSIS OF SALIVARY DNA EVIDENCE
FROM A BITEMARK ON A BODY SUBMERGED IN WATER. J FORENSIC
SCI 1994; 44 (5): 1069-1072.

12.LESSIG R, WENZEL V, WEBER M. BITE MARK ANALYSIS IN FORENSIC ROUTINE CASE
WORK . EXCLI JOURNAL 2006;5:93
13. AVON SL. FORENSIC ODONTOLOGY: THE ROLES AND
RESPONSIBILITIES OF A DENTIST. J CAN DENT ASSOC 2004;70(7):453-
458.
14.HIREMATH SS. TEXTBOOK OF PREVENTIVE AND COMMUNITY
DENTISTRY.2007, 1ST EDITION: ELSEVIER ; 283-293.
15.C.MICHAEL BOWERS DDS ,JD, TEXTBOOK OF FORENSIC DENTAL
EVIDENCE AN INVESTIGATION HANDBOOK, SECOND EDITION
16.DAVID.R.SEN ,RICHARD A WEEMS TEXTBOOK OF MANUAL OF
FORENSIC ODONTOLOGY , FIFTH EDITION.
17. www.FORENSIC ODONTOLOGY…………__ PAST, PRESENT & FUTURE
Dentistryzone Developed for the benefit of dental professionals.mht
18.FISCHMAN SL. THE USE OF MEDICAL AND DENTAL RADIOGRAPHS IN
IDENTIFICATION. INT DENT J 1985; 35; 301-6.
19. REDDY VM, SAXENA S, BANSAL P. MANDIBULAR CANINE INDEX AS A SEX
DETERMINANT: A STUDY ON THE POPULATION OF WESTERN UTTAR PRADESH. J
ORAL MAXILLOFAC PATHOL 2008;12:56-9
20.JANARDHANAN M, UMADETHAN B, BINIRAJ K R, VINOD KUMAR R B,
RAKESH S. NEONATAL LINE AS A LINEAR EVIDENCE OF LIVE BIRTH:
ESTIMATION OF POSTNATAL SURVIVAL OF A NEW BORN FROM PRIMARY
TOOTH GERMS. J FORENSIC DENT SCI 2011;3:8-13

• 21. ACHARYA AB. FORENSIC DENTAL AGE ESTIMATION BY MEASURING
ROOT DENTIN TRANSLUCENCY AREA USING A NEW DIGITAL TECHNIQUE. J
FORENSIC SCI. 2014 MAR 7
• 22.Brown KA. Forensic aspects of community dentistry. Ann Acad Med
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