Bite Mark

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BITE MARKS :

BITE MARKS Dr. Jinesh P. S. 10/07/2013

Contents :

Contents Introduction Examination & preservation of bite marks Collection of bite mark evidence from suspect Bite mark analysis & comparison Patterned injuries V/S human bite mark Self inflicted wounds Biting on objects other than skin Factors affecting analysis Admissibility Summary

Forensic Odontology:

Forensic Odontology Diagnostic and therapeutic examination and evaluation of injuries to jaws, teeth, and oral soft tissues Identification of individuals, especially casualties in criminal investigations and/or mass disasters Identification, examination, and evaluation of bite marks which occur with some frequency in sexual assaults, child abuse cases & in personal defense situations. Paul G. Stimson, Curtiz A. Mertz. Forensic Dentistry 1997

Bite Marks :

Bite Marks Registration of the cutting edges of teeth on a substance caused by a jaw closing Physical alteration in a medium caused by contact of teeth Representative pattern left in an object or tissue by dental structures of an animal or human Patterned injuries Pressure abrasion, contusion, laceration or combination Dental fingerprints No two individuals will have the exact same dentition in regards to shape, size and alignment of teeth Ajaykumar . Textbook of Forensic Medicine 2011, Bernard Knight. Forensic Pathology. 2 nd ed. 1996

Causes of Bite Marks:

Causes of Bite Marks Human teeth Animal teeth Objects that mimic teeth (artifacts) Body part lying on a displaced dental prosthesis Injuries caused by bangles, shoe heels, watch stripes may mimic Krishan Vij . Textbook of forensic Medicine & Toxicology. 5 th ed. 2011, Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Circumstances :

Circumstances In violent crimes Attacker may bite the victim or vice-versa In sexual offence cases Common sites are face, breasts, abdomen, thighs, pubis, shoulders etc Child abuse Common sites are arms, hands, cheeks, buttocks, trunk & shoulders Love bites Are part of acceptable sexual intercourse Krishan Vij . Textbook of forensic Medicine & Toxicology. 5 th ed. 2011

Circumstances cntd… :

Animal bites Self-inflicted to fabricate injuries Motives ranging from gain to psychiatric disorder Multiple suction type bite marks on accessible areas shoulder & arms – M C in older children and teenage girls Inflicted / suffered during sporting events Football, wrestling, boxing etc Bite may be seen on inanimate objects at the scene Bite marks on food stuffs / fruits Circumstances cntd … Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010 , Krishan Vij . Textbook of forensic Medicine & Toxicology. 5 th ed. 2011, Bernard Knight. Forensic Pathology. 2 nd ed. 1996

Objectives of B M Analysis :

Objectives of B M Analysis Examination Documentation Interpretation Preservation Differentiation of a human bite / animal bite / artifacts Comparison with that of accused Ajaykumar . Textbook of Forensic Medicine 2011, Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Examination & Preservation Procedure Protocol:

Examination & Preservation Procedure Protocol Recognize the lesion as bite mark & collect salivary DNA Photograph the bite mark Orientation photographs Close-up photographs Dust / lift the bite mark Take an impression of bite mark Removal & preservation of bite mark Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Recognize the Lesion as Bite Mark :

Recognize the Lesion as Bite Mark First & most critical step Recognize the patterned injury as human bite marks Usually noted first by crime scene investigator, medical examiner, casualty doctor / sister Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Collection of Salivary DNA:

Collection of Salivary DNA A positive link between the bite mark & the biter Swab the area with a sterile saline / water-soaked cotton swab Submit the swab to the police for DNA analysis Bite mark on a living individual should be examined by forensic odontologist or medical officer as quickly as possible Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Collection cntd…:

Collection cntd … Salivary DNA will be absent in washed bite wounds, medically treated or the bite was made through clothing The clothing should be preserved Area under the clothing should be analyzed for saliva Clothing along with Crime scene photograph should be sent to forensic odontologist Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Salivary Analysis :

Salivary Analysis Saliva may contain blood group substances Buccal epithelial cells and leucocytes of gingival fluid will be present in saliva Umadethan B, Forensic Medicine 1 st ed. 2011

Orientation Photograph :

Orientation Photograph Responsibility of first responder, medical examiner and / or forensic odontologist Photographs showing the location of bite mark on the body Can assess the relative positions of the biter & the victim Better to take at scene Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Close-up Photograph :

Close-up Photograph Capture the B M with and without a scale or ruler Capture in different angles, esp perpendicular Should be photographed using variety of techniques Black & white Digital Ultraviolet Infrared Alternate light sources Video For orientation, biter position, later comparison, time and age of bite Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Dusting & Lifting of B M :

Dusting & Lifting of B M Dusting with fingerprint powder Lifting the bite print with gel filter / standard fingerprint tape & photographed Enhances the pattern injury on deceased Will get third dimension of the wound Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Impression of the B M:

Impression of the B M To document the third dimension To compare to a suspect in scene of ‘matching’ Made on a standard dental impression material – PVS (polyvinyl siloxane) Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Procedure … :

Procedure … A retention material should be placed on soft material Gauze / gem clips Dental dye stone is then poured over it Orientation marks should be placed When set, lift it from the body Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Impossible …:

Impossible … Avulsion of tissues at bite site Extensive amount of swelling / bleeding Difficult – living victim Indentations often dissipate by time of examination Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Re-examination :

Re-examination Preferably few days after first autopsy The appearance may markedly enhanced Faint lesions may become more prominent Even absent lesions, appear for first time 2 days after death Bernard Knight. Forensic Pathology. 2 nd ed. 1996

Removal of Bite Mark :

Removal of Bite Mark Secure the bite mark to a retaining ring Custom formed dental plastic ring, PVC pipe Ring should be at least 1 cm in all directions away from the bite mark Tissue be glued with cyanoacrylate & sutured Ring with bite tissue should be lifted & apply scalpel to remove epidermis and dermis from the underlying fat Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Removal cntd…:

Removal cntd … Photograph under side of the tissue & donor site Tissue must be kept in a transparent container & transilluminated Record transillumination photographically Should be preserved in 10 % formalin Care should be taken to deal emotional impact of victim’s family Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Bite Mark Evidence from a Suspect :

Bite Mark Evidence from a Suspect As quickly as possible After getting request of the police or direction of court With / without consent Photograph full face & close-ups of teeth Perform an oral examination & dental charting Create a bite record in wax / PVS / Alginate Prepare an impression on impression plaster / dental stone / plaster of Paris Take maxillary & mandibular impressions –PVS & duplicate – silicones Obtain dental history Mathiharan K, Patnaik A. K. Modi’s Medical Jurisprudence and Toxixology . 23 rd ed. 2010; Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Points to be noted :

Points to be noted Dental charting – Odontogram Charting of any missing teeth Estimate the bite overhang, edge to edge occlusion, undershoot projection Recording of broken teeth, irregularity, marked variation in cutting edge profile Evaluation of size & prominence of any teeth Evaluation of any abnormality in orientation, gaps and irregular spacing Bernard Knight. Forensic Pathology. 2 nd ed. 1996

PowerPoint Presentation:

Odontogram designed for Interpol – displays each surface of each tooth

Bite Mark Analysis :

Bite Mark Analysis To determine the patterned injury is a human / animal / patterned injury that mimics human B M Class characteristics – dental arches forms that are recorded in the media, whether it be skin or an inanimate object Individual characteristics – pattern left by the teeth of the biter Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Goals of Analysis :

Goals of Analysis To find out position of the biter in relation to victim Age of biter (child V/S adult) Time of bite relative to the time of death of victim Estimation of the amount of force used Dental profile of the biter Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Techniques for Bite Mark Analysis :

Techniques for Bite Mark Analysis Photographic comparison 1 Photograph of bite mark & photograph of bite impression made on wax by suspect is compared Computer axial tomography Scanning electron microscopy Video imaging Radiography Use of fingerprint powder to dust the impression Transparent overlays – (M C) Analysis of bite made using 1 : 1 transparent overlay of the biting surface of the suspect’s dentition placed over a 1 : 1 photo of the bite 1. Umadethan B. Principles and Practice of Forensic Medicine. 1 st ed. 2008 2. J. Payne-James, Roger W. Byard . Corey T. S, Henderson C. Encyclopedia of Forensic and Legal Medicine 3 rd vol. 2005

Current Overlay Techniques :

Current Overlay Techniques Computer based Radi0-opaque wax Hand-traced from wax Hand-traced from study casts Xerographic J. Payne-James, Roger W. Byard . Corey T. S, Henderson C. Encyclopedia of Forensic and Legal Medicine 3 rd vol. 2005

Three-dimensional Imaging :

Three-dimensional Imaging Newer technique 3 dimensional laser scan can be used More scientific & quantitative 3 dimensional animation will be more useful in future J. Payne-James, Roger W. Byard . Corey T. S, Henderson C. Encyclopedia of Forensic and Legal Medicine 3 rd vol. 2005

PowerPoint Presentation:

3 dimensional laser scan

PowerPoint Presentation:

3 dimensional animation

Scanning Electron Microscopy :

Scanning Electron Microscopy To detect individual characteristics Acrylic or epoxy impressions of bite mark and impression will be prepared Coat with carbon to make them conductive to electric bean Scan the specimen in 3 dimensions Take photographs the view which show maximum correlation Have high degree of certainty Umadethan B, Forensic Medicine 1 st ed. 2011

Human Bite Mark:

Human Bite Mark Usually only a small part of dental arcade Caused by front teeth canine to canine with an invariable gap at either sides representing separation of jaws Near circular or shallow oval Continuous / intermittently interrupted line / parallel linear tracks – rare Forcible / love bites Krishan Vij . Textbook of forensic Medicine & Toxicology. 5 th ed. 2011, Bernard Knight. Forensic Pathology. 2 nd ed. 1996

PowerPoint Presentation:

Forcible Love bites Extensive subcutaneous bruising that may spread laterally & blur the outline Appearance – two bows concavities facing each other with a gap at each end Anywhere on body Suction patechiae – caused by firm application of the lips which form an air tight seal against skin and the sucking action reduces the air pressure at centre. Shower of petechial haemorrhages to appear from rupture of small superficial venules in S C tissue If forcible – petechiae will be confluent & bruise / hematoma may develop Usually on – neck, breast in love play / sexual assault Bernard Knight. Forensic Pathology. 2 nd ed. 1996

Age of Bite Mark :

Age of Bite Mark Very difficult Due to intrinsic differences in wound profile and victim physiology, features such as color or texture etc are not reliable UV photography is useful in study Histological study 2 Enzyme histochemistry 2 Free histamine, 5 HT Immunological study 2 Glycophorin a component of erythrocyte membrane Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010 Umadethan B. Principles and Practice of Forensic Medicine. 1 st ed. 2008

PowerPoint Presentation:

immediately following biting episode 5 minutes after the episode after 20 minutes after 1 hour

Age & Histology of Bite Mark :

Age & Histology of Bite Mark Age Findings 0 – 4 hrs Serum, RBC & fibrin deposited on bite mark 2 – 6 hrs Infiltration with neutrophilic leucocytes 8 hrs A layer of neutrophilic leucocytes under epithelial injury 12 hrs Three distinct layers; 1 ) superficial – fibrin & RBC 2) Middle – neutrophils 3) Deep – damaged collagen 30 hrs Epithelial degeneration begins at the edge 72 hrs Distinct growth of epithelium 5 – 7 dys Sub-epidermal granulation appears, perivascular chronic inflammatory cells seen 8 – 12 dys Overlying epithelium becomes thick & hyper-plastic; new collagen fibers appears 12 – 14 dys Thinning of epithelium due to atrophy & collagen fibers become prominent Umadethan B. Principles and Practice of Forensic Medicine. 1 st ed. 2008

Animal Bites :

Animal Bites Commonly dogs; rarely large cats, bears, alligators, crocodiles etc Usually multiple Animal bites often cause shear rather than impact injuries, producing lacerations Characterized by a narrow anterior dental arch and consist of deep tooth wounds over a small area Deep parabolic arch or U – shaped Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010, Bernard Knight. Forensic Pathology. 2 nd ed. 1996 S. L. Avon. Forensic Odontology: The Role and Responsibilities of the Dentist.. J Can Dent Assoc, 2004; 70(7) ; 453 - 8

Animal bite cntd…:

Animal bite cntd … Dogs – more likely to cause avulsion of human tissue during violent biting Cat – small and round with pointed cuspid -tooth impressions Most animal bites on deceased are as a result of scavenging Witness testimony should be evaluated with physical evidence and circumstances of the event When controversies exists, evaluated by veterinarians, wildlife officers, police agencies, medical examiners, forensic odontologist Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010, Bernard Knight. Forensic Pathology. 2 nd ed. 1996 S. L. Avon. Forensic Odontology: The Role and Responsibilities of the Dentist.. J Can Dent Assoc, 2004; 70(7) ; 453 - 8

PowerPoint Presentation:

Human Dog

Bite Mark Protocol for Animal Bites :

Bite Mark Protocol for Animal Bites Examine animal for blood and visible transfer of evidence from victim Gather the victim’s DNA from animal’s claws Immediately take the animal to a veterinarian to induce vomiting Strain the contents; preserve tissue and cloth fragments or other foreign bodies found in vomitus for comparison Quarantine the animal for collection of feces and compare evidence of hair, tissue, bone, and clothing Take dental impressions of the suspect animal Test victim & animal for rabies Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Patterned Injuries :

Patterned Injuries When a hard object is pressed into a soft material As a result of A heavy force over a short period of time A deceased person lying on an object for a long time Post–mortem patterned injuries – ants (M C), fishes & scavengers Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Pattern Analysis Protocol :

Pattern Analysis Protocol Know the circumstances of the event Thorough crime scene investigation Obtain witness statements Document the injury Photograph, swab for salivary DNA, overlay tracing, take impressions Remove patterned injury & preserve Microscopic examination of patterned injury Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Biting in Objects other than Skin :

Biting in Objects other than Skin Food materials should be processed Collect saliva for DNA analysis Photograph & preserve the evidence Dolonak D, Matches E, Lew E. Forensic Pathology; Principles & Practice 1 st ed. 2010

Preservation of Materials :

Preservation of Materials Bite mark on butter, cheese, lard, wax, chocolate etc should be stored in refrigerator to prevent melting or gradual flowing Bite marks on fruits should ideally be preserved in Campden solution (a metabisulphite ) or 5 % acetic acid in 40 % aqueous formaldehyde Bernard Knight. Forensic Pathology. 2 nd ed. 1996

Factors Affecting Human B M:

Factors Affecting Human B M Contour of the surface – irregular, curved may receive proportionate part of the bite Amplitude and direction of biting force Movement of assailant and / or victim during time of bite Sucking action Period of contact Missing teeth / grossly displaced teeth / damaged teeth will impart peculiar architecture Capacity of wounds to change during healing Krishan Vij . Textbook of forensic Medicine & Toxicology. 5 th ed. 2011

Problems in Analysis :

Problems in Analysis Deformability & elasticity of human skin Healing power of human skin Human skin – not a good recording medium Movements of victim & accused Ajaykumar . Textbook of Forensic Medicine 2011

Admissibility of B M Evidence :

Admissibility of B M Evidence Uniqueness of the Dentition may not translate into a Unique Bite Mark Human B M are highly variable – single individual can inflict different pattern of B M Bite mark do not render a positive identification when related to the world population Bite mark evidence can be 100 % exclusionary in certain situations “Positive identification”, “positive match”, “the bite marks were left by the suspect”– deemed unacceptable by American Board of Forensic Odontology J. Payne-James, Roger W. Byard . Corey T. S, Henderson C. Encyclopedia of Forensic and Legal Medicine 3 rd vol. 2005

Summary – Human Bite :

Summary – Human Bite Collect saliva for DNA analysis Remember possibility of bite through clothing Photograph with ruler / scale – close & orientation Photograph with UV, IR & ALS Dust & lift Take impression Preserve Don’t wash or medically treat before swabbing Don’t dissect before photographing

Summary – Animal:

Summary – Animal Review all scene photograph Collect salivary DNA Photograph Follow animal bite protocol Don’t give opinion before analyzing the evidence and knowing the circumstances on the event

Summary – Bite on other than Skin :

Summary – Bite on other than Skin Swab for DNA photograph Impressions Preserve for later analysis

THANK YOU :

THANK YOU