Human Bite marks and it's classifications , difference from animal bites , methods of recording it , softwares used for analysis and comparison

1. Human
bite marks

2. CONTENTS :
 Its Identification
 Types of Bite
 Classification
 Difference between Animal and Human bite
 Methods of recording
 Comparison and final analysis
 Available Softwares
 Conclusion

3. BITE MARKS
 Defined by MacDonald as a mark caused by the teeth
alone or in combination with other mouth parts
 Either caused by humans or animals, They maybe on
tissue, food items or on objects
 Biting is considered to be primitive type of assault and
results when teeth are employed as a weapon in an act
of Dominance
 Associated with sexual crimes, violent fights and child
abuse hence plays an important role in forensic
odontology
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4. HUMAN BITE MARKS
 Human bite marks are the tool marks left by the action of
teeth and other oral structures during the biting of objects
or people by a person
 Most commonest form of evidence presented in criminal
court
 “Sweet and Pretty” considered the size, shape, pattern of
Incisal or biting edges of upper and lower teeth to be
specific to an individual
 “Rawson and Associates mathematically calculated that
biting edges can be arranged in 1.36 ×10 to power 26
different combinations to depict unique pattern of biters teeth
 This is crucial to identify a suspect or to exclude an innocent
person both of which are equally signifiacnt
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5. IDENTIFICATION OF HUMAN BITES
 Sweet has suggested that human bite marks maybe
identified by following characteristics
* Gross Features : A circular or elliptical marks found
on the skin with a central area of echymosis. The
circular mark is caused by upper and lower arches
while the central area of echymosis is due to sucking
action.
* Class Features : The marks produced by different
classes of teeth are usually distinct, allowing one to
differentiate tooth type within a bite mark
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6.  Incisors produce rectangular marks, canines are triangular or
rectangular depending on the amount of attrition, premolars
and molars are spherical or point shaped
Class Features Indivisual Features
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7. * Individual features : Class features may in turn have
characters such as fractures, rotations, spacing etc.
* Sites of Bite marks :
• Bite marks may be found on any part of the body .
However females are most often bitten on breast and
inner part of thighs as a result of sexual assault
• Male children are prone to be bitten on genitals, result of
sexual abuse
• Adult males are bitten on fingers, arms and shoulders,
most oftenly during fights
Child
Adult male
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8. MECHANISM OF BITE MARKS
Three predominant mechanisms associated with production of
bite marks
* Tooth pressure marks are caused by direct pressure
application by incisal edges of anterior teeth or occlusal edges
of posterior teeth, clinical presentation of tooth pressure
indicates pale areas representing incisal margins
* Tongue pressure is caused when the material is taken into the
mouth and pressed by tongue against teeth or palatal rugae and
distinctive marks are present due to tongue sucking
* Tooth scraping against tooth surface commonly invloving the
anterior teeth . Clinical presentation can be in the form of
scratches and abrasion, that indicate irregularity and pecularity
of incisal edges are useful in identification.
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9. TYPES OF HUMAN BITES
 Types of human bites are mainly of seven types, which can be
classified by four types of impressions
A)Hemorrhage: Undamaging mark on skin
B)Contusion : Ruptured blood vessels, bruise
C)Lacerations : Punctured or torn skin
Hemorrhage
Lacerations
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10. D) Incision: Near puncture of skin
E) Avulsion : Removal of skin
F) Artifact: Bitten of piece of skin
Incision
Avulsion
Artifact
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11. G) Abrasion: A scrape on skin
The following classes are proven significant in practical application
* Class 1) It includes diffused bite marks which is having limited class characteristics and lacks
individual characteristic such as bruise , diffused bite marks
* Class 2) This pattern of injury reffered to as a single arch bite or the partial bite mark as it has
some individual and some class characteristicas
* Class 3 ) This classifiacation includes both individual as well as class characteristics .
It is used for comparision purposes. The main sites for this are buttocks, shoulder, an upper
arm or chest . The pressure and deep penetration of tissues is held to record the lingual
surfaces of anterior teeth.
* Class 4) Mainly avulsion or laceration of tissues is caused by the bite. Class characterstics and
individual characterstics are not present. This bite is commonly found where there is avulsion
of ear or finger
Abrasion
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12. Factors Influencing Appearance Of
Bite Marks
 The appearance of bite mark is influenced by both the
mechanism and forces that produce them and by the
mechanical properties of the skin or subcutaneous tissues or
other bitten materials.
A) Site variation : Bite marks vary from site to site because
they are modified by mechanical properties of tissues
eg: The tissues of the breasts are innately softer than those of
the back
B) Directional variation : At given sites due to pre-existing
tension lines in the skin is known as Langers line. Flexion,
extension and roatation of surface skin markings follow the
pattern of these lines .
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13. C) Other factors : Such as curvature of the surface bitten,
dragging during the biting process, structure and
vascularity of the tissue, medication,environmental
factors etc.
D) Clothing : Through which the bite is inflicted, effects
the injury to some extents.
The age of the injury in the time elapsed from
its infliction to the analysis and the damaged tissue .
Reliable determination the age of antemortem skin
injuries require histopathologic changes of the alleged
incident
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14. Histopathological and Clinical changes to monitor the time elapsed in bite
injury
TIME
PREDOMINATE
CELLULAR
INFILTRATE
HEALING
CLINICAL
COLOUR
HOURS
4-8
12
16-24
24-36
Predominant
cellular infiltrate
PMNs
Macrophages
PMNs
---------
Peripheral
fibroblast
Red blue purple
Blue black
DAYS
1-3
>3
4
4-5
6
10-14
Central necrosis
Hemosederin
Collagen fibers
Capillary growth
Lymphocytes
Granulation tissue
Green-blue
Brown yellow green
Tan yellow
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15. CLASSIFICATION
 MacDonald has stated that as Any field of specialisation gets
established, it requires the development of specific
nomenclature and systems of classification, As a study of bite
marks developed over the past 5 decades, numerous authors
have tried to classify the injury.
I) Cameron and Sims classification : A relatively
simple wide encompassing classification, This is based on the
type of agent producing the bite marks and the material
exhibiting it.
i) Agents
a)Human
b)Animals
ii) Materials
a)Skin, Body tissues
b)Food stuffs and other materials
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16. II) McDonalds Classification :
The most sited, McDonlad suggested an etiological
classification. This is pertinent for human bites but also
applicable to marks on other material
i) Tooth pressure marks :
Marks produced on tissue as a result
of direct application of pressure by teeth. These are generally
produced by the incisal and occlusal surface of teeth.
ii)Tongue pressure marks:
When sufficient amount of tissue is
taken into mouth, the tongue presses against rigid areas such
as lingual surface of teeth and palatal rugae. The marks thus
left are reffered to as sucklings .
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17. iii)Tooth scrape marks:
These are the marks caused due to
scraping of teeth across the bitten materials.They are usually
caused by the ‘Anterior teeth’ and presents as scratches or
superficial abrasions.
III) Webster’s Classification : It is not uncommon to note
bite on food stuff. This is especially in case of theft or robbery at
house or shopping centers
i) Type 1 :
The food items fractures readily with limited depth of
tooth penetration eg: Hard chocolate
ii) Type 2 :
Fractures of fragment of food item with considerable
amount of tooth penetration eg: Bite marks on apple
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18. iii) Type 3 :
Complete or near complete penetration of food
item with slide mark eg: cheese
Type 1
Type 2
Type 3
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19. IV) Degree of penetration :
i) Clearly defined :
It is produced when significant pressure is applied
while biting .
ii) Obviously defined :
It is produced when pressure of first degree is
applied while biting.
iii) Quite noticable :
When a violent pressure is used during the bite.
iv) Lacerated :
The skin is violently torn from the body
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20. How human bite is different from
animal bite
 Not frequently forensic dentists are requested to investigate
animal bites, Such bites are usually produced by dog family
(dog,wolf,fox), cat family(domestic cat,tiger,leopard),
Rodents(rats), snakes, sharks and crocodiles.
 A study of the dentition of different animal species is known
as comparative dental anatomy.
 Animals are primarily classified as vertebrates i.e with
vertebral columns and invertebrates.
 Vertebrates- Fishes, mammals, reptiles, amphibian
 Invertebrates- annelids, arthropodes, cnideria
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21.  Characteristics of some vertebrates
a) Fishes :
 A major function of teeth in fish is to seize or grasp prey and
they usually have conical shape teeth hence called as homodont .
This is the characteristics of most fishes.
 There are some fishes however, They have some different shape
heterodont teeth. Hence knowledge of specific morphologic
patterns is required
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22. b) Reptiles :
 The reptilian dentition is primarily used in combat and to
grasp prey. They typically have a row of only conical or only
cuspid teeth which are ‘homodont’.
 However they may vary in size, are ankylosed , simple rooted
and polyphydont.
 The teeth do not occlude and only simple jaw movements
could be seen hence they consume small sized prey to swallow
completely.
 CROCODILES:
They have a complex dentition i.e they have
periodontal fibres.
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23.  SNAKES:
Snakes have modified dentition to release poison
called ‘fangs ’ which contains canals or grooves for venom
release.It is interesting to know that poisonous and non
poisonous snakes have different types of dentitions.
Non venomous snakes have two rows of maxillary
teeth, whereas venomous snakes have a single row. Palatal to this
a pair of poison delivering fangs are present.
Snake Bite Mark
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24. C) Mammals :
 Mammals are characterised by heterodont dentition. Teeth
are attached by periodontal ligament to the bony socket.
Usually there are only two sets of dentition(diphydont)
where the primary dentition is replaced by permanant teeth.
The teeth usually consists of enamel, dentin and cementum
and posterior teeth are usually multi rooted.
Teeth are specialised for functions such as mastication, So
the teeth inter digitate and occlude.
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25. Dental features of few mammals
A) Dog family (canidae) : The denatl formula for the dog family or
canidae is “I3/3 C1/1 P4/4 M2/3 ” The incisors have a high central
cusp with mesial and distal lobes adopted for holding, tearing
and crushing . The canine tooth is long and strong, while the
upper fourth premolar and lower first molar are adapted as
carnassial teeth which are used for shearing food.
Dog skull Dog bite
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26. B) Cat family (felidae) : The dental formula for the cat family is
I3/3 C1/1 P3/2 M1/1 , The felidae have a dentition i.e
specialised for grasping and killing prey by slicing the flesh.
The incisors are similar to canidae but the canines are longer
and stronger. In addition the premolars and molars are
reduced in number. The upper 3rd premoalar and lower 1st
molar form the carnassial teeth. Felines display a short snout,
with the incisors arranged in approximately straight lines
across the front of the mouth and large canines at the
corners.
Cat bite 24

27. C) Bear family (ursidae) : Generally the dental formula is
I3/3 C1/1 P4/4 M2/3 . Murmann and co-workers state that
ursidae differ from both the canidae and felidae but they are
more likely to the cat family. The anterior portion of the
maxillary arch is only slightly curved and the corresponding
region of the mandibular arch is very straight
Bear Bite
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28.  In regions where there is a threat of accidental or predatory
carnivorous attacks, the subsequent need to identify the
animal species causing the bite is essential from an
investigative and ecological point of view .
 A characteristics feature of carnivore is the specialisation of
one posterior tooth in each quadrant called the carnassial
tooth. These consists of a blade like upper tooth that slices
against the buccal surface of opposing lower tooth, which
produces a scissor like cutting action
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29. d) Rodents (rodentia) : The rat family have chisel shaped
continually erupting incisors with a diastema between the
incisors and molars . They have no canines or premolars. The
general dental formula is I1/1 C0/0 P0/0 M3/3, The labial
surface of incisors is covered with enamel,while the lingual
surface has cementum. Although rodents seldom attack
humans, there are instances when these animals have
nibbled at the extremities of dead bodies, producing peculiar
injuries it was to rule out foul play . Also Brown has reported
cases where damage was inflicted on electric cables and fire
extinguisher hoses.
Rat bite
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30. HUMAN ANIMAL
ARCH SIZE Broad, U-shaped Narrow anterior aspect
ARCH SHAPE Circular or oval V- shaped and elongated
TEETH Broad central and narrow
lateral incisor;
More blunt
Broad lateral, narrow
centrals , sharper and longer
canines
INJURY PATTERN Commonly bruising ;
Laceration and avulsion less
common
Severe laceration and
avulsion ;
Greater skin damage
SITE Breast,abdomen,nipple,
thigh,back,shoulders
Extremities such as
feet,legs,hands,arms ;
Exposed skin
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31. BITE MARK INVESTIGATIONS
Drinnan and Melton, as well as Sweet have emphasised that
any attempt at bite mark investigation should begin with
following questions
Is the injury a bite mark ?
If a bite, was it caused by human teeth ?
Was it caused by adult or child ?
Does the age of the bite mark correspond to time and type of
crime ?
Are there any unique, individual characteristics in the bite
marks ?
Can these characteristics be compared to the teeth of the
suspect ?
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32. METHODS OF EVIDENCE COLLECTION
Evidence collection from victim :
 Ideally, bite mark evidence should be collected when it is first
presented and observed. If a suspected bite mark is criminal in
nature, it must be informed to law enforcement authorities .
When a case with suspected bite mark is identified, a primary
concern is patient care . Therefore at no time should collection of
bite mark evidence interfere with timely patient treatment .
This is emphasised since Pretty and associates have found human
bites to be more infectious(includes transmission of HIV,
Hepatitis-B and syphilis ) especially when the bite injury presents
as an abrasion or laceration .
The protocol for bite mark evidence collection that follows has
been recommended by the American board of forensic
odontology (ABFO)
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33. a)Case demographics: Vital information pertaining to the case
should first be noted . Eg : Name, Age and Sex of the victim
as well as case number , date of examination and name of
examination
b) Visual examination : Visually examining the bite mark and
document the following :
 Orientation and location of the mark
 Type of injury
 Colour, size and shape
 Contour, Texture and elasticity of the bite site
 Differences between upper and lower arches and between
individual teeth
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34. c) Photography: Photographs provide a permanent records of bite
marks. No time should be wasted to collect pictures. Since the
injurieschange its appearance rapidly due to healing.Colour and
black and white photographs from different angles may be taken.
Desirably two views are preffered.
i) Orientation photographs :Photographs that depict the
location of bite mark on body.
Orientation
Photography of a
bear bite victim
Close-up Photography
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35. ii) Close up photography: These should be made with a rigid
refferance scale (such as ABFO NO 2 scale) that is placed on the
same place as the bite marks. The entire bite mark and the scale
should be visible on the photograph . A close-up photograph
depicting the bite mark without the scale can also be made to
indicate that no part of the mark has been marked by scale. The
camera should be positioned directly over the injury site with long
axis of the lens perpendicular to the surface of the bitten skin.
According to Pretty and Sweet , this decreases the distortion of the
images due to off-angle camera position.
When the victim is alive , photographs are repeated every 24
hours for 3-4 days to record progressive changes in appearance of
bite marks.
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36. d) Saliva swabs: It is reasonable to assume that a bite cannot be
inflicted without leaving saliva behind. Saliva deposited on skin
may have WBCs and sloughed epithelial cells which may be a
source of DNA , enabling direct link to the suspect . Hence
swabing the bite areas for saliva traces can prove invaluable in
investigations.Care should be taken to not wash the bitten area
before swabing.Clark also stated that clothes also should be
swabbed for saliva traces.
Saliva swabing
34

37. e) Impressions of bite marks : Impressions of bite site should be
taken when indicated according to American board of forensic
odontology bite mark analysis guidelines. Dental acrylic or
plaster can be used as a rigid support for the impression to
accurately record the curvature of the skin. Use vinyl poly
siloxane poly ether or other impression material available in the
dental office i.e recommended for fixed prosthetic application.
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38. f) Bite printing records : It is similar to the method of lifting
finger prints from crime scenes, finger print lifting tape can be
used to lift the non perforating bite marks ofter brushing the
bite mark with finger prints lifting powder . Excellent clarity
and details are obtained with this method . There is no
expertise required to lift the print and the versatility and the
use of the finger print powder and brush technique is yet to be
exlpored .
g) Video tape documentation : The video tape
documentation demonstrated the three dimensionally of the
bite in motion. The video equipment should be selected on the
basis of four criteria like its portability , its quality of the image
produced , its ease of use of the final image . This equipment
can range from essential equipment such as extension cords ,
play back units , editing units .
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39. Video tape Recording
37

40. h) Radiographic documentation : Bite marks can also be
interpreted through soft tissue radiography. It has the advantage
of penetrating the tissues there by revealing damage that might
not be observed in photographic approach . Xeroradiography and
contrast enhanced radiography can add valuable informatio and
should be considered as an adjunct to standard photographic
procedures
i) Electron microscopic documentation : Electron microscopy
requires access to the sophisticated and expensive equipment but
can be invaluable investigative tool for the odontologist .
Scanning electron microscopy is used for detailed examination of
surface configuration of bite mark .
Energy dispersive x-ray analysis can be used along with scanning
electron microscopy to enhance the surface topographic feature of
bite mark.
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41. Evidence collection from the suspect
Evidence collected from the victim of a bite mark should be
complimented with evidence from a suspect of the
perpetrated bite. Such evidence must be obtained from the
suspect using a signed and witnessed inform consent or a
court order.
Following a detailed clinical examination (intra oral and extra
oral ) , the items of evidence recovered should include
Photographs of suspects teeth in occlusion and open bite
Maxillary and mandibular impressions made with rubber
base impression material or irreversible hydrocolloid and
models poured in dental stone. Bite registration thin sheet of
wax may be made if impressions are available .
Saliva swabs preferably from the buccal vestibule should be
obtained for comparing with the swab collected from the bite
mark
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42. 40

43. Comparison And Bite Mark analysis
Comparison technique :
According to ABFO the most widely used method for comparison of
bite mark evidence are generation of overlays (acitate), Test bite
media eg: Wax exemplars, styroform . Recently software
programmes such as Adobe Photoshop is suggested by Johansen
and Bowers to compare dental profiles. With its use transparent
overlays can be created which are then laid over the bite marks
41

44. Several methods of bite marks comparison have been documented
in the literature. All the documented methods are chiefly
comprised of three steps
i) Registration of bite mark and suspects dentition
ii) Comparison of bite mark and dentition
iii) Analysis of similarity and dissimilarity
42

45. The advantages of using computerised system are accurate
measure of physical parameters of the evidence , less
photographic distortion , eliminates any examiner subjectivity ,
good image visualisation , standardisation of comparison
procedures are reproducibility of results .
Laboratory evaluation of bite marks :
Recovery of salivary DNA has been the main focus of biological
techniques in bite mark analysis . The advantages of this method
is that the DNA recovered from saliva on the bite mark is usually
sufficient to produce a profile .
Extreme environmental circumstances are to be taken into
consideration . The salivary DNA may be highly degraded . It can
be assorted by the environment . A new area in biological
technique is the use of the bacterial finger print . There are over
two thousand recorded species of oral bacteria and each
individual has a unique bacterial population . A bacterial profile
can be generated by recording the different species of bacteria’s
present . This can be used to create data base in future.
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46. Bite mark analysis
Any analysis involves two steps first discovery and preservation of
evidence and second involves evaluation, comparison and findings of
the recovered evidence
In analysing bite mark first it should be determined if the injury is a
bite mark and whether it is caused by human teeth , consistency of
marks with the time of the crime should be determined .
To standardise the analysis of bite mark the American board of
forensic odontology established the following guidelines in 1986.
a) History : Thorough history of any dental treatment carried out
after the suspected date of the bite mark should be taken
b) Photography : Extra oral photographs including full face and
profile views, Intra oral should include frontal views , two lateral
views and an occlusal view of each arch and a photograph of
maxiamal mouth opening
c) Extraoral examination : Soft tissue and hard tissue factors that
may influence biting dynamics . Measurements of maximal opening
and any deviation on opening or closing should be noted.
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47. d) Intraoral examination : Examination of tongue and
periodontal status like mobility of teeth . In case of recent marks,
they should be swabbed for DNA from saliva left in the wound
e)Impressions : Two impressions of each arch using materals that
meet the ADA specification . The occlusal relationship should be
recorded .
Putty Impression
Alginate Impression
45

48. f) Sample bites : Sample of suspects bite in centric occlusion
using wafer of base plate wax or silicone putty material . The
sample is photographed immediately and used for future
comparison .
g) Study cast: These are prepared using type 2 dental stone.
Study casts
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49. Drawbacks in Bite marks Analysis
a) Doubts have been raised about the accuracy of the bite
imprint as skin is considered a poor medium for accurate
impressions due to curves and other irregularities producing
intrinsic distortion. Thus comparison of a person’s teeth to
bite mark on a bite mark on a victim’s body is prone to error
lerading to gfalse implications of persons crimes they did not
commit.
b) Unlike fingerprints , which are stable for lifetime ,the
dentition is capable of major changes in configuration, with
and without proffessional intervention.
Teeth lost due to extraction, trauma or exfoliation,
changes in sizes and relationship of arches due to growth or
orthodontic procedures, alterations of biting surface by
restorative materials, caries and changes in position of teeth
due to periodontal disease.
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50. c) The uniqueness of human dentition has not been definitely
established. Also a bite mark is not an overall accurate
representation of teeth , tongue and jaw movements are also
involved.
d) Questions about reliability of bite mark investigations arise due
to different examiners arriving at opposite conclusions. Till date
there is no standard comparison procedure for bite marks .
Ultimate outcome depends on an examiners objectivity and
methods used.
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51. Available softwares
A) Bite print software :
It is a semi automatic software developed.
 Materials and Methods :
Each tooth mark was approximated as an ellipse and the dental arch as
a semi circumference to represent the bite mark as a set of geometric
coefficients for comparison with the biting edges of the dental casts.
The procedure is briefly described below.
 Software implimentation :
Developed by a computer program in C++ with the microsoft visual
studio 2005 professional edition using the Qt 4.3.0 library,libtiff, QGL
viewer, openGL graphics library. The software was successfully tested
inMicrosoft Windows XP Professional version2002 and in Windows
7,8 and 10 operating systems using a PC with Intel Pentium Dual Core.
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52. Photograph of bite marks on the skin :
 Development of BitePrint software was based on bite mark
photographs of the skin of victims in real forensic cases with
the court’s decision as gold standard, although the possibility of
error can never be completely ruled out.
 Photographic distortion of the bite marks was corrected
according to the Johansen and Bower method4. Bite Print
software approximates each tooth mark in the bite mark as an
ellipse, using the ABFO No. 2 scale as the coordinate system.
First, the expert draws the two axes (mesiodistal length and
bucco-lingual width)of each tooth mark, with the software
ensuring that both are perpendicular and displaying the initial
ellipse.
 Second, the software automatically adjusts the initial ellipse to
the tooth mark by computing the image. The software
measures the colour inside the ellipse and also in the closest
surrounding area. For each point of the mentioned areas, the
software tests whether the colour corresponds to the tooth
mark or not.
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53.  Once the software computes the image, it runs an algorithm
to fit the ellipse to the tooth mark (the algorithm is available
from the authors on request). Figure 1 depicts ellipses
calculated by BitePrint for the tooth marks of a human bite
mark.
 The dental arch is represented by automatically fitting a
semi-circumference to the tooth marks, depicted by the
ellipses (see Figure 2). A minimum of three non-aligned
ellipses is needed for the determination of the semicircle.
The software establishes the circumference that best fits all
calculated ellipses, using an algorithm to determine the
circumference that passes through the centres of the ellipses
with the minimum error.
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54. 52

55.  Once the circumference is determined, the expert marks a point
between the central incisor marks, and the software, then draws
a line from this point to the centre of the circumference. This
line is used to calculate the angular position.
 The software automatically computes the following parameters
to characterize the bite mark (see Figure 3):
(a) Distance to the arch (mm): the distance from the centre of the
circumference (the arch of the dentition) to the centre of the
ellipse (the tooth).
(b) Angular position (°): the angle between the centre of the
circumference and the radius from the centre of the
circumference to the centre of the ellipse.
(c) Eccentricity: the relationship between the major and minor
axes of the ellipse.
(d) Rotation (°): the angle between the major axis of the ellipse
and the tangent of the circumference that passes through the
centre of the ellipse. The rotation ranges between –90 and 90
degrees
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56.  (e) Inter canine distance (mm): each ellipse is tagged as
Unknown by default, but the user can identify it as an incisor,
canine, premolar or molar tooth. If the user has chosen two
canine labels, the program automatically calculates the inter
canine distance as that between the centres of the two
ellipses corresponding to the canines. The maxillary inter
canine distance has proven to be a highly reliable parameter
for the identification of human bite marks.
The user can save all calculated parameters for further
comparisons
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57. 55

58. Biting edges from 3D-images of dental casts obtained with
Dental Print :
 Quantitative comparison of tooth marks on a photograph
with biting edges taken from a dental cast requires that the
same procedure is used to compare both images. Biting edges
from 3D-images of dental casts (see Figure 4) were generated
with Dental Print software, as described
 There is no difference in the application of Bite Print
between a bite mark photograph and the image of biting
edges obtained with Dental Print. Bite Print adjusts ellipses
to the biting edges and a semi-circumference to the dental
arch, yielding the same variables from dental casts, i.e.
distance to the arch, angular position, eccentricity, rotation
and inter canine distance
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59. 57

60. Other available softwares :
 B) Adobe photoshop software : This softwares includes
Scanning of the bite marks : Photograph of bite mark is
scanned and resized to lifesized photograph . The
impressions of the suspects dentition is obtained and cast are
poured . Casts are applied with seperating media and allowed
to dry , the casts are pressed moderately into stamp pad such
that the occlusal plane is parallel to the surface of the pad to
select the incisal edges . Then the casts are scanned along
with ABFO scale no.2 placed beside it
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61. The scanned image is transferred to adobe photoshop . The
magic wand tool cursor is clicked on the blue coloured
incisal edges of the teeth . This tool selects an area of similar
pixel tool .
Construction of the overlay : Since the overlay will be on a
layer separated from the background a new layer is created.
The selected edges are outlined by clicking
edit > stroke> dialogue box > stroke
width>1>location>inside>ok>ctrl+D .
Non-metric analysis of bite mark and suspect dentition :
After completion of bite mark image and overlay a non
metric analysis is undertaken this involves a super imposing
the overlay over the bite mark injury and investigation point
of concordance or discrepancy .
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62. C) 3D Imaging for bite analysis :
It is similar to that of bite print software .
CONCLUSION :
Following comparison , a bite mark analysis
may have one of the following concluding
statements as suggested by Levine and ABFO
a) Definite biter : There is reasonable medical
certainly to indicate that the bite mark has
been produced by the suspects dentition .
There is concordance of sufficient distinctive, individual
characteristics to confer uniqueness within the population
under consideration.
b) Probable biter : Bite mark shows some degree of specificity to the
suspects teeth by virtue of a sufficient number of matching
points including some corresponding individual characterstics.
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63. c) Possible biter: The bite mark and suspects dentition are
consistant altough the suspects teeth could have made the
bite mark, there are no characteristics matches to be
absolutely certain . Matching points are general or few and
there are no incompitable in consistencies .
d) Not a biter : The bite mark and suspects dentition are not
consistent –features on the bite mark indicate that the
suspects teeth have definitely not caused them .
Analysis of bite mark evidence has been
assisting the judiciary to answer crucial questions about
interactions between people at the seen of a crime. The shape
of the bite mark can give useful clues about the person who
caused it and may lead to the implication or exclusion of an
individual under investigation.
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64. Refferences
 Shafer’s textbook of oral pathology- 8th edition
 Text book of oral medicine by Anil Ghom
 Journal of Indian academy of Forensic Medicine., July-sept 2014
 Review article on Bitemarks as a physical Evidence from the crime
scenes by Dr Kapil verma, Bhavana Joshi.
 Journal of Forensic Sciences and criminology Volume 4
(ISSN:2348-9804)
 Review article on Analysis and Identification of Bite marks in
forensic dentistry by Dr Sandeep Kaur.
 Research article on 3D imaging for bite mark analysis by Dr
Sam T Evans , Carl D Jones.
 Australian Journal of Forensic Sciences.
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