Forensic odontology


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Forensic odontology

  1. 1. 1
  2. 2.  Introduction  Historical Background I. Personal Identification 1)Comparative Identification 2)Reconstructive Identification a)Identification of Ethnic origin (Race) b)Sex determination c)Age estimation II. Role of Dental team in mass fatality incidents III. Bite marks a)Definition b)Classification c)Identification d)Investigations e)Analysis 2
  3. 3. IV. Recognition and reporting of Domestic Violence, Abuse & Neglect a)Child abuse, neglect b)Domestic violence; intimate partner violence, spousal abuse & battered women c)Recognition of elder abuse & neglect V. Malpractice VI. Lip prints VII. Palatal rugae patterns VIII. Identification from Dental DNA 3
  4. 4. INTRODUCTION  The word Forensic is derived from the Latin words ‘forum’, which means ‘court of law’ & ‘forensic’ which means public. Odontology refers to the study of teeth.  Forensic odontology, therefore, has been defined by Federation Dentaire International (FDI) as “that branch of dentistry which, in the interest of justice, deals with the proper handling and examination of dental evidence and with the proper evaluation and presentation of dental evidence”. 4
  5. 5. Forensic dentists are responsible for following main areas of practice.  Identification of found human remains (age, sex, race) (Personal identification)  Identification in mass fatalities.  Assessment of bite mark injuries.  Assessment of cases of abuse.  Civil cases involving malpractice.  Lip prints in identification.  Palatal reguae pattern in identification.  Identification from dental DNA. 5
  6. 6. HISTORICAL BACKGROUND  In 2500 BC, two molars linked together by gold wire found by Junker in a tomb at Giza.  Tooth impressions were deliberately utilized for legal personal identification as far back as 900 years.  First formally reported case of dental identification was that of 80 years old warrior JohnTalbot, who fell in the battle of Castillon in 1453.  In 1775 Dr. Paul reverse identified JosephWarren with help of a bridge made of silver ivory.  First time, the dental evidence was accepted in US courts was Webster Parkman case in 1849. 6
  7. 7.  The first treatise on forensic odontology as a subject was done by Dr. Oscar Amoedo. His publication was entitled L’Art Dentaire En Medicine Legale and acquired worldwide recognition and he is recognized as the Father of Forensic Odontology.  In 1967 Russian source reported that dental evidence was responsible for identification of badly charred bodies of Adolf Hitler & Eva Braun. 7
  8. 8. Personal Identification 8
  9. 9. I. PERSONAL IDENTIFICATION  Identification is the establishment of a person’s individuality.  Acharya &Taylor defined identity as “the characteristics by which a person may be recognized.  Proper identification of the dead / living persons is required for both legal and humanitarian reasons. It may help in the settlement of property, facilitate remarriage of a surviving spouse and allow the cremation or burial of the body, according to relevant religious and cultural customs.  The positive identification of living or deceased persons using the unique traits and characteristics of the teeth and jaws is a corner stone of forensic odontology. 9
  10. 10. •Traditional methods of identification have included visually recognizing the body, and personal property such as clothing, jewelry etc.These methods, however are not very reliable in establishing the identity of a person. For example, visually identifying a body that is burned or decomposed can be very traumatic experience for relative and friends. •The better option for identification is for forensic experts to analyze physical features present in the body. Physical features may be inherited or acquired. •Therefore the use of dental evidence is the method of choice in establishing the identity of badly burned, traumatized, decomposed and skeletonized remains. 10
  11. 11. BASIS FOR IDENTIFICATION  The basis for dental identification is the theory that human dentition is never the same in any individuals. Morphology and arrangement of teeth vary from person to person.  Teeth may have restorations, which may after their original morphology.  The number of combinations, 16 missing teeth can produce is approximately 600 million.  Four missing and four filled teeth in a mouth combined can produce more than 700 million combinations.  Every tooth has five surfaces, if, instead of considering the whole tooth, the surface were taken individually, the variations produced would be astronomic. 11
  12. 12.  Fillingham and co-workers, calculated that there are 1.8x1019 possible combinations of 32 teeth being intact, decayed, missing or filled. 12
  13. 13. DENTAL IDENTIFICATION PROCEDURES  There are 2 forms of dental identification procedures. 1) Comparative identification 2) Reconstructive identification or dental profiling. 13
  14. 14. 1. COMPARATIVE DENTAL IDENTIFICATION  This method involves the comparison of ante mortem and post mortem dental records to determine if the body is that of the person of interest.  It includes 4 steps: 1) Oral autopsy 2) Obtaining dental records 3) Comparing post and ante mortem dental data and 4)Writing a report and drawing conclusions. 14
  15. 15. (I) ORAL AUTOPSY:  Autopsy also known as necropsy or post mortem, involves examination of the deceased, usually with dissection to expose the organs to determine the cause of death.  Autopsy has a systematic protocol starting with critical examination of the external features of the body such as gender, ethnicity, build, wounds, scars, tattoos and body piercing photographs, radiographs, finger prints, fingernail scrapings and hair sample.  Oral examination is an essential part of the post mortem procedure.The forensic dentists who conduct oral autopsy should have adequate knowledge about common post mortem findings such as Rigor mortis, Livor mortis, Decomposition, and post mortem artifacts. 15
  16. 16.  Rigor Mortis:This is a state of stiffening of muscles, sometimes with slight shortening of the fibres. Individual cell death takes place at this stage.  Rigor mortis render the jaws rigid and the use of mouth gags or intra oral myotomy is essential for jaw separation.  Teeth may become brittle in burned cases, they need to be reinforced with cyanocrylate cement, polyvinyl acetate or clear acrylic spray paint prior to examination.  Access for radiography in incenerated bodies can obtained by removing tongue and contents of the floor of the mouth in a ‘tunneling’ fashion from beneath the chin.  The status of each tooth (whether intact, carious, restored or missing) should be noted.  A thorough examination of soft tissue injuries, fractures and presence of foreign bodies is under taken and samples of hard and soft tissues should be obtained. 16
  17. 17.  All post mortem information pertaining to the body must be entered on to the standard ‘Interpol Post mortem Form’ which is color coded in pink. 17
  18. 18. (ii) OBTAINING DENTAL RECORDS  Dental records contain information of treatment and dental status of a person during his / her life.  Dayal and colleagues state that dental records may be obtained from the treating dentist, specialist or hospital records.  Whenever possible, the original record should be examined, such records may in the form of dental charts, radiographs, casts and / or photographs.  The contents of all available dental records should be transcribed onto the standard ‘Interpol Antemortem Form’ which is colour coded in yellow. 18
  19. 19. (iii) COMPARING POST AND ANTE MORTEM DENTAL DATA  Once the post mortem evidence and dental records are available, the data can be compared.  Features compared include tooth morphology and associated bony structures, pathology and dental restorations.  An individual with multiple dental treatment and unusual features has a better likelihood of being identified. However, that does not imply that identification relies on extensive dental treatment, comparison should take into account quality rather than quantity. 19
  20. 20. PROBLEMS WITH DENTAL IDENTIFICATION 1)Absence of antemortem records. 2)Absence of acquired dental tracts for identification. 3)Limitations for storing dental records for certain period. 4)Poor quality dental records. 5)In post mortem situation, all of the teeth may not be 6)recovered as a result of post mortem trauma or loss of Pdl. 7)Fire can result in irreversible changes to restorations and teeth which can reduce the amount of information available for comparison. Despite these problems, teeth and dental tracts are one for the most valuable individualizing features of human body. 20
  21. 21. 2.RECONSTRUCTIVE POST MORTEM DENTAL PROFILING:  Dental profiling includes extracting a triad of information. 1)The decedent’s ethnic origin (Race). 2) Gender 3) Age  Dental profiling is used in cases in which there is no suspection as to who the decedent may be.  According to pretty and sweet, “the information from this process will enable a more focused search for ante mortem records”. 21
  22. 22. a) IDENTIFYING ETHNIC ORIGIN FROMTEETH:  Physically, humans are a diverse species.This diversity is a result of genetic influences, as well as environmental factors such as climate and geographic location. Therefore, the people of the world look different.  Traditionally, the human species has been categorized into three ‘races’ – Caucasoid, Mongoloid, Negroid.  Many of the best traits of estimation of race are found in the mid facial skeleton, including the area of nose, mouth and cheek bones. Landmarks such as shape of the cranium, lateral projection of zygomatic arches, shape and contour of the orbits and nasal aperture, shape of the arches can provide information about racial differences. 22
  23. 23.  Harvey has delineated some social and ethnic characteristics S. No. Chinese Europeans 1. Wide arch Narrow arch and crowding 2. Enamel extension between roots of molars Cusp of carabelli 3. Five cusped third molars 4. Three rooted deciduous molars 23
  24. 24. S. No. Australian American Indians 1 . Large arch and large teeth Marked attrition 2. Marked attrition Shovel shaped incisors 3. Midline diastema Large teeth S. No. Mongoloid Negroid 1. Occlusal enamel pearls in premolars Lower 1st premolar has two or three lingual cusps 2. Missing mandibular incisors 3. Shovel shaped incisors 24
  25. 25.  Complexion: It is of limited value,The skin is brown in Indians, fair in Europeans and black in Negroes. Skin color is changed by decomposition, burning etc.  Eyes: Indians have dark eyes, a few brown eyes, Europeans have blue or gray eyes.  Hair: Indians have black and thin hair. Europeans have fair or light brown or reddish. Indians, Negroes have wooly hair (i.e., arranged in tight spirals). 25
  26. 26. Mongolian hair is coarse and dark and uniform and usually circular on cross section and has a dense uniform pigmentation and dark medulla. Negro hair is elongated, oval on cross section and has a dense pigment with an irregular distribution. Caucasian hair has round or oval shape on cross section with uniform distribution of fine or coarse pigmentation. Clothes: The dress may be helpful sometimes. Skeleton: The cephalic index (C.I) or index of Breadth is important. C.I. = Maximum breadth of skull x 100 Maximum length of skull 26
  27. 27. Racial Difference in the Skull S. No. Type of skull Cephalic Index Race 1. Dolico-cephalic (Long headed) 70 to 75 Pure Aryans, Aborigines and Negroes 2. Mesati-cephalic (Medium headed) 75 to 80 Europeans & Chinese 3. Brachy-cephalic (Short headed) 80 to 85 Mongolian 27
  28. 28. Racial Difference in the Skull S. No. Trail Caucasian (White) Mongolian (Yellow) Negro (Black) 1. Skull Rounded Square Narrow & elongated 2. Forehead Raised Inclined Small & compressed 3. Orbits Triangular Higher, rounded Lower, wider, square 4. Nasal Aperture Narrow & elongated Rounded Broad 5. Palate Triangular Large & rounded or horse shoe Long & rectangular 28
  29. 29. Teeth Poorly spaced and crowded Evenly shaped Aligned, more or less parallel to each other Face Small Large, flattened Jaw & molar bones projecting teeth oblique Upper extremities Small, with short distal segments Long in proportion to body forearms longer in proportion to arms; hands small 29
  30. 30. Thelengthandbreadtharemeasuredbycalipersandnotbymeasuring tape.TheskullofanIndianisCaucasianwithfewNegroidcharacters. Fromthevariousmeasurementsoftheskull,racecanbedeterminedby 85-90%ofcases.Becauseofracialmixingalltheskullsmaynotbe correctlydifferentiatedintothethreeraces. Lower extremities Small Legs longer in proportion to thighs; feet wide & flat; heel bones projecting backwards Lumbar vertebrae Anterior measurement exceeds posterior by 5.6 mm Posterior measurement exceeds anterior by 5.8 mm Lumbar curve is straightened 30
  31. 31. Religion:  Hindu males are not circumcised, sacred thread, necklace of wooden beads, caste marks on forehead, tuft of hair on back of head and piercing of ear lobes if present are helpful.  Hindu females may have vermilion on head, silver toe ornaments, thali, tattoo marks, nose-ring aperture in nostril, few openings for ear – rings along the helix.  Muslim females may have nose ring aperture in septum only, several opening in the ears along helix and usually no tattoo marks.  Muslim males are circumcised. Dental features have a complex mode of inheritance and are a combination of hereditary and environmental factors to which a person is exposed. As a result, today different populations show considerable diversity in their dentition. For population identification, those dental features that have a stronger genetic and weak environmental influence are useful. 31
  32. 32. Dental features used to describe population differences are broadly categorized as metric (tooth size) and non metric (tooth shape).  Metric features are based on measurements and non metric in terms of presence or absence of a particular feature, eg: whether carabelli’s cusp is present or not.  Townsend cites numerous studies which indicate metric features are considerably influenced by local environmental factors, eg: missing lateral incisors causes compensatory increase in central incisor. Space constraints in the jaws result in compression of third molars.  On the other hand, non metric features are more inheritable and therefore, dependable in establishing the population group to which and individual belongs. 32
  33. 33. NON METRIC DENTAL FEATURES: Given by Scott &Turner . (1) Crown Features:  Shoveling:The presence of prominent mesial and distal marginal ridges on the lingual surface of the upper and lower anterior teeth, usually the maxillary central incisor.  Double shoveling: Mesial and distal marginal ridges on the labial and lingual surface of the upper central incisor.  Carabelli’s feature: Expressed as slight grooves or well- developed tubercles on the mesiolingual cusp of the upper first molar.  Three cusped upper 2nd molar:The distolingual cusp of (hypocone) of the upper molars is retained on the first molar but, tends to be of reduced size or completely absent in the second molar. 33
  34. 34.  Cusp 5: An occlusal tubercle on the distal marginal eidge of the upper first molar.  Cusp 6: A supernumerary cusp on the distal aspect of the lower first molar between the disto lingual and the distal cusp.  Cusp7:A supernumerary cusp expressed between the mesiolingual and distolingual cusps of the lower first molar. It appears wedge-shaped from the occlusal aspect, with the base of the wedge placed lingually and apex towards the central pit.  Winging:This is an indirect crown trait. It is characterized by the bilateral labial rotation of the distal margins of maxillary central incisors.The incisal edge of the central incisors, taken together, appears ‘V’ shaped from the occlusal aspect.  Five cusped lower 2nd molar:The lower 2nd molar can present a distal cusp (hypo coneclid). 34
  35. 35.  Lower molar groove pattern:Occlusal groove configurations (‘X’, ‘Y’ and ‘+’) on the lower 1st and 2nd molars are also used in population identification.  Interruption groove: A developmental groove expressed on the cingulum and lingual aspect of the root of upper lateral incisor.  Enamel extension: Seen on the upper and lower molars and premolars. Here, the cervical margin of the enamel projects apically. Such projections deviate 1-4 mm from the horizontal axis of the cervical line. For population identification, the upper or lower molar is considered.  Odontome: Conical projection on the occlusal surface of either upper or lower premolar.The tubercle has enamel and dentin components and involves pulpal extensions almost half the time. It is an extremely rare feature. 35
  36. 36.  Lateral incisal variants: Include peg shaped diminutive andT- forms of the highly polymorphic upper lateral incisor. Scott andTurner state that few studies have been done on these features.  Distal accessory ridge: An additional ridge between the lingual ridge and distal marginal ridge of maxillary canine.  Premolar accessory ridge: Additional ridge between the triangular ridge of the buccal cusp and mesial and / or distal marginal ridges of premolars. Bothe maxillary and mandibular premolars can be used for population identification.  Premolar accessory marginal tubercle: A tubercle on the mesial and / or distal marginal ridges of upper premolars.  Premolar lingual cusp:The presence of two or more lingual cusps on the lower second premolar. 36
  37. 37.  Mesial marginal complex of upper molar:Tubercles observed on the mesial marginal ridge of upper first molar.  Parastyle:Tubercle on the buccal surface of the upper molars.  Protostylid:The presence of a tubercle on the mesiobuccal cusp of the lower molars. Population identification focuses on the lower 1st molar. 2. Root features:  Two-rooted upper premolar: Although widely regarded as having two roots the upper first premolar root number does show population variations.  Two rooted upper molar:The absence of root furcation (either one or both) in the upper second molar.  Two rooted lower canine: Presence of two rooted canines is a rarity among humans, although typical in non human primates. 37
  38. 38.  Tomes root: Presence of extra root on the lower first premolar.  Three rooted lower molar: Presence of a third root, usually lingual to the distal root, on the lower first molar.  Single rooted lower molar: Lower molars commonly have two roots, but fused roots are not uncommon. Although this trait is most common in the third molars, the 2nd molars are used for population identification.  The range of dental variation among humans is so great that several characteristic features must be considered together before concluding on ethnic group) origin.The high and low frequency of a given non metric feature is important in identification:  Example: People of European,West & South Asian origin may exhibit four cusped lower 2nd molar, two rooted lower canine, Carabelli’s feature and three cusped upper 2nd molar, in relatively high frequency. 38
  39. 39.  But, features like winging, shoveling, double shoveling, odontomes, cusps 5, 6 & 7, Enamel extension, ‘Y’ groove pattern,Tomes root, and three rooted lower 1st molar do not occur often among them. But most of these features are commonly seen among East-Asians. b) SEX DIFFERENTIATION: Determining the sex of unknown human remains is the second step in the triad of building a dental profile. Sex has to be determined in cases of heir ship, marriage, divorce, legitimacy, impotence, rape etc., sex can be determined by characteristics of body, morphology of different bones, metric features, as well as DNA analysis of teeth. 39
  40. 40. S.No. Traits Male Female 1. Gonads A functioning testis, penis, prostrate A functioning ovary, uterus, vagina etc. 2. Build Larger with greater muscular development Small with less muscular development 3. Shoulders Broader than hips Narrower than hips 4. Waist ill defined Well defined 5. Trunk Abdominal segment smaller Abdominal segment larger 6. Thorax Dimensions more Dimensions less 7. Limbs Longer Shorter 8. Arms Flat on section Cylindrical on section 9. Thighs Cylindrical Conical, due to shorter femur and greater deposition of fat 10. Gluteal region Flatter Full and rounded 40
  41. 41. 11. Wrists and Ankles Not delicate Delicate 12. Breasts Not developed Developed 13. Pubic hair Thick and extends upwards to the umbilicus (Rhomboidal) Thin, horizontal and covers mons veneris only (Triangular) 14. Body hair Present on face and chest Absent on face and chest 15. Head hair Shorter, thicker, coarser Longer, thinner, finer 16. Larynx Prominent, Length 4.8 cm Not prominent, length 3.8 cm 41
  42. 42. Trait Diagnostic of sex from skeleton: 1. General Features: 42 S.No. Traits Male Female 1. General size Larger, more massive Smaller, slender 2. Long bones Ridges, depressions and processes more prominent, bone of arms and legs are 8% longer Less prominent 3. Shaft Rougher Smoother 4. Articular surface Larger Smaller 5. Metacarpal bones Longer and broader Shorter and narrower 6. Weight 4.5 kg 2.75 kg
  43. 43. 2. Skull: 43 S.No. 5.Traits Male Female 1. General appearance Larger, longer (dolicocrania) Smaller, lighter, wall thinner rounder (brachycrania) and smoother 2. Capacity 1500-1550 cc 1350-1400 cc 3. Architecture Rugged, muscle ridges more prominent especially in occipital and temporal area Smooth 4. Forehead Steeper, less rounded Vertical, round, full, infantile
  44. 44. 5. Glabella More prominent Small or absent 6. Fronto nasal junction Distinct angulation Smoothly curved 7. Orbits Square, set lower on the face, relatively smaller, rounded margin Rounded, higher, relatively larger, sharp margins 8. Supra orbital ridges Prominent Less prominent or absent 9. Check bones Heavier, laterally arched Lighter, more compressed 10. Zygomatic arch More prominent Less prominent 44
  45. 45. 11. Nasal aperture Higher and narrower, margins sharp Lower and broader 12. External auditory meatus Bony ridge along the upper border is prominent Often absent 13. Frontal eminences Small Large 14. Parietal eminences Small Large 15. Frontal sinuses Much developed Less developed 16. Occipital area Muscle lines and protuberance prominent Muscle lines and protuberance not prominent 17. Mastoid process Medium to large, round, blunt Small to medium, smooth, pointed 18. Base Sites of muscular insertions more marked Sites of muscular insertion less marked 45
  46. 46. 19. Digatric groove More deep Less deep 20. Condylar facet Long and slender Short and broad 21. Occipital condyles Large Small 22. Palate Larger, broader, tends more to U-shape Smaller, tends more to parabola 23. foramina Larger Smaller 24. Foramen Relatively large and long Relatively small and round 46
  47. 47. 3. Mandible: 47 S.No. Traits Male Female General size Larger and thicker Smaller and thinner Chin Square Rounded Body height At symphysis greater At symphysis smaller Ascending ramus Greater breadth Smaller breadth Angle of body and ramus Less obtuse (under 125 ) prominent is everted More obtuse, not prominent, inverted Condyles Larger Smaller
  48. 48. 4. Pelvis: 48 S.No. Traits Male Female 1. Bony frame work Massive, rougher, marked muscle sites Less massive, slender, smoother 2. General Deep funnel Flat bowl 3. Ilium Less vertical, curve of iliac crest reaches higher level and is more prominent More vertical, distance between iliac crests is less, iliac fossae, shallow, curves of crest well marked 4. Pre auricular sulcus (attachment of anterior sacroiliac ligament) Not frequent, narrow, shallow More frequent, broad and deep 5. Acetabulum Large, 52 mm in diameter, directly laterally Small 46 mm in diameter, directed anterolaterally
  49. 49. 6. Obturator foramen Large, often oval with base upwards Small, triangular with apex forwards 7. Greater schiatic notch Small, narrower, deeper Larger, wider, shallower 8. Ileo pectineal line Well marked and rough Rounded and smooth 9. Ischial tuberosity Inverted Everted, more widely separated 10. Body of pubis Narrow and triangular Broad, square and pits on posterior surface if borne children 11. Ramus of pubis It is like continuation of body of pubis Has a pinched or narrowed appearance and is short and thick 12. Ischiopubic rami More everted Less everted 49
  50. 50. 13. Symphysis High Low and distance between two pubic tubercles greater 14. Sub pubic angle ‘V’ shaped, sharp angle 70-75 ‘U’ shaped, rounded broader angle, 90-100 15. Pelvic brim / inlet Heart shaped Circular or elliptical, more suspicious 16. Pelvic cavity Conical and funnel shaped Broad and round 17. Pelvic outlet Smaller Larger 18. Sacro-illiac articulation Large, extends to 2 1/3 to 3 vertebrae Small, oblique, extends to 2 to 2½ vertebrae 50
  51. 51. 19. Sacrum Longer, narrower, with more evenly distributed curvature, promontory well marked, body of 1st sacral vertebrae larger Shorter wider, upper half almost straight, curve forward in lower half, promontory less marked, Body of 1st social vertebrae smaller 20. Coccyx Less movable More movable 21. Ischio pubic index = Pubic length in mm / Ishical length in mm x 100 73 to 94 91 to 115 22. Sciatic notch index = Width of sciatic notch / Depth of sciatic notch x 100 4 to 5 5 to 6 51
  52. 52. 5. Scapula: 52 S.No. Traits Male Female 1. Height More than 157 mm Less than 144 mm 2. Glenoid cavity Height greater (39.2 cm) Height less (32.6 cm)
  53. 53.  Sex Chromatin:  It is a plano convex mass, lying near nuclear membrane (Barr body). In the buccal smear, the percentage of nuclei containing chromatic body ranges from 0-4 in males and 20- 80 in females. In females neutrophil leukocytes contains a small nuclear attachment of drumstick form (Davidson body) in upto 6% of cells.This is absent in males. In decomposed bodies sex chromatin cannot be made out.  In normal cases, sex determination is easy from external examination only, but it is difficult in cases of 1) Hermaphroditism. 2) Concealed sex. 3) Advanced decomposition. 4) Skeleton. 53
  54. 54.  SEX DIFFERENCES INTOOTH SIZE: Teeth are useful for differentiating sex by measuring their mesiodistal and buccolingual dimensions. Lund and Mornstad state that “this is of special importance in young individuals where skeletal secondary sexual characters have not yet developed”.Tooth size or odontometrics are influenced by environment and are therefore population specific and do not apply to the world at large. The canines consistently show the maximum sex difference, premolars, first and second molars as well as maxillary incisors are also have significant differences. 54
  55. 55.  DENTAL INDEX:  Incisor index (Ii) – Proposed by Aitcheson Ii = [MDI2] x 100 [MDI1]  MDI2 – Maximum mesiodistal diameter of maxillary lateral incisor  MDI1 – Maximum mesiodistal diameter of maxillary central incisor.  This index is higher in males  Mandibular canine index – proposed by Rao & Associates  Mean mesiodistal canine dimension in female + S.D +  Mean mesiodistal canine dimension in males – S.D. 55
  56. 56. The value obtained using this formula was 7.1 i.e., 7.1 mm is the maximum possible mesiodistal dimension of mandibular canines in females.The same dimension is greater in males.  Turner proposed that ‘Distal Accessory ridge”, a non metric feature on the canine “is the most sexually dimorphic crown tract in the human dentition, with males showing significantly higher frequencies and more pronounced expression than females”. 56
  57. 57. AGE DETERMINATION  It is final step in the triad of dental profiling.  The estimation of age plays an important role in forensic identification.  The dentition is one of the four systems used in estimating physiologic age, the others being bone development, secondary sex characteristics and stature and weight.  Dental age is one of the few measures of physiologic development that is uniformly applicable from infancy to late adolescence. After attaining maturity, teeth continue to undergo changes, making age estimation possible among adults. 57
  59. 59. DENTAL AGE ESTIMATION METHODS:  Dental age estimation makes use of morphologic, radiographic, histological and biochemical methods to examine age dependent changes in teeth. Age estimation using the dentition may be grouped into 3 phases. 1. Aging in prenatal, neonatal and early post natal 2.Age estimation in children and adolescents and 3. Age estimation in adults 59
  60. 60. 1. AGE ESTIMATION IS PRENATAL, NEONATAL AND EARLY POSTNATAL CHILDREN:  The primary tooth germ begins to form at seven weeks in utero (IU) and the enamel formation of all deciduous teeth is usually complete by the first year.  Among the permanent teeth, the first molar shows germ formation first at about 3.5-4 months IU. Age estimation in this group of individuals can be very accurate. It makes use of histological techniques, which enable observation of tooth mineralization upto 12 weeks before it is actually apparent on radiographs. However this requires specialist training.The advantage that radiography has is that it is ‘non invasive’, requiring no tissue dissection. 60
  61. 61.  The neonatal line is considered as an indicator of birth. Bowen’s attributes its formation to the slowing down of enamel prism growth rate, this “creating an apparent line of demarcation”. 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 neonatal line proves that the individual was ‘stillborn’.  In cases of age estimation of skeletal remains, where histological and radiographic studies are not possible, an alternative method is to measure the dry weight of the mineralized tooth cusps – developed by stack.  The developing teeth in a child at six months IU weight about 60 mg, 0.5 g in a newborn and 1.8 g at 6 months post natal. 61
  62. 62. 2. AGE ESTIMATION IN CHILDREN AND ADOLESCENTS:  Two events that may be used to measure dental age in children and adolescents are tooth emergence or eruption and tooth calcification.  Nystrom and colleagues consider the estimation of age by study of tooth eruption as a convenient clinical method. It involves visual assessment of teeth present in the mouth and require little expertise or equipment.  The use of tooth emergence for age estimation should, however, be limited to deciduous teeth.There emergence is under genetic control and is relatively regular, commencing approximately a 6 months and completing by 2.5 years.  On the other hand, emergence patterns of permanent teeth are under the influence of the intra oral environment, being affected by infection, arch space and premature tooth loss. 62
  63. 63.  Therefore evaluation of radiographs to assess tooth calcification is a much better alternative, since: 1) Calcification can be observed from radiographs for a period of several years. 2) It is not altered by local factors such as lack of space, infection etc. 3)The study of tooth calcification also let us assess age at periods when no emergence takes place (2.5-6 years and > 12 yrs)  Dental calcification is considered by Schmeling and associates as one of the three most suitable methods of estimating age in criminal procedures.  Age estimation in this group is accurate since a number of teeth passing through various stages of calcification are available. Hence dental calcification is accepted as a better indicator of age in first two decades of life. 63
  64. 64.  Schous and Massler’s Method:  Schous and Massler described 20 chronological stages of tooth development starting from 4 months IU until 21 years of age.This chart is based on histological sections which permit direct comparisons with radiographs. Ubelaker included additional data in this chart.  Dental development of males and females were combined and each stage included the amount of age variation.  Demirjian’s method: Demirjian and co-worker developed an age estimation method that made use of a scoring system.The development of seven mandibular teeth on the left side was divided into eight stages each.These stages were named ‘A’ to ‘H’, while third molars were not used in the original method, a recent study by Chaillet and Dimiriian accommodates them. 64
  65. 65.  Each tooth is assigned ‘maturity score’ that corresponds to its developmental stage.The maturity score is assigned for each tooth is added and a total maturity score.  The total maturity score is then plotted on a chronologic ‘age conversion table’. Separate maturity scores and age conversion tables developed for both sexes.  It is the most popular method for assessing age in children and adolescents, probably due to the detailed description and radiographic illustrations of tooth developmental stages and its relative simplicity. 65
  66. 66.  Third molars in Age Estimation:  Although the third molar is a valuable indicator of age in the age group of 16-23 yrs.When all other teeth have completely developed, its accuracy in age estimation in questionable due to their variation in genesis, position, morphology and time of formation.  Based on Kohler and coworkers 10 stage developmental scoring method, Gunst and associates concluded that the age of an individual, specifically whether the individual is 18 yrs old or not can be reliably estimated using specific formulae.  When all 4 third molars have completely calcified, the chances of the individual being 18 yrs old is 96.3% and 95.1% for males and females respectively.  When only one or two third molars present, the lower third molars are the best predictors of whether an individual is 18 yr old. 66
  67. 67.  Growth variations exist between different population groups due to dissimilar genetic and environmental factors. Ideally, therefore, population specific developmental data is essential for optimized age estimation. 3. AGE ESTIMATION IN ADULTS: Age estimation in adults is challenging when compared to younger age groups. Ritz and colleagues stated that following completion of growth, changes in the dentition used to estimate age “are influenced not only by the age of the individual, but also by numerous endogenous and exogenous factors, such as disease, nutrition and physical strain”. 67
  68. 68. a) Gustafson’s Method: In 1950, Gosta Gustafson developed a method for age estimation based on morphological and histological changes of the teeth.This assessed regressive changes such as:  Amount of occlusal attrition (A)  Coronal secondary dentin deposition (S)  Loss of periodontal attachment (P)  Cementum apposition at the root apex (C)  Root resorption at the apex (R)  Dentine translucency (T) For each of these regressive changes or variables, different scores ranging from 0-3 were assigned.This meant attrition could have any one of four scores (A0, A1, A2 or A3) and similar one of four scores for the other variables. 68
  69. 69. Advantages of Gustafson method:  It used 6 variables. Each variable had its own effect on final score, but since as many as six variables were used, a larger variation is one of the variables would not influence the final result to any great extent. Limitations:  None of the variables could be used alone in the method except dentin translucency, which gives the most acceptable age estimates when used alone.  Training in histological techniques were necessary.  Equipment such as stereomicroscope was required.  When only one tooth is used, the age range increased significantly.  Age range also increased on teeth over 50 yrs old. 69
  70. 70. b) DentinTranslucency: Bang and Ramm were the first to use dentin translucency for estimating age.  Root translucency increases with increasing age.  Root dentin starts to become translucent during the third decade of life beginning at the apex and advancing coronally.  It is due to the decreased diameter of dentinal tubules caused by increased intra tubular calcification. Hence, the difference in refractive indexes between intra tubular organic and extra tubular inorganic material is equalized, resulting in increased translucency of the affected dentin. 70
  71. 71. Disadvantages of using translucency included:  Irregular junction of translucent and non translucent zones, thereby making it difficult to measure the length.  Under estimation of age in older age groups.This could be due to slowing down of dentinal sclerosis, since most of the root would already be sclerosed by old age, thus restricting further increase in translucency. c) Age estimation from incremental lines of cementum:  Acellular cementum incremental lines are used in estimation. Mineralized unstained cross sections of teeth, preferably mandibular central incisors and third molars are used.  The pathological state of the periodontium and / or desmodontium may compromise the precision of aging. 71
  72. 72. d) Amino acid racemisation:  All humans use amino acids exclusively in protein synthesis.  Aspartic acid is an amino acid that has a rapid rate of racemisation i.e., it gets spontaneously converted from one type (L-Aspartic acid) to another (D-Aspartic acid) with increasing age.  Therefore, there is a constant change in the ratio of L and D aspartic acid at different ages and this ratio may be used for age estimation.  Racemisation rate of aspartic acid is high in root dentine and therefore teeth are valuable sources for ageing using this method. 72
  73. 73.  GROWTH IN BONES: The bones of the human skeleton are performed in hyaline cartilage.This soft tissue model is gradually converted into hard osseous tissue by the development of osteogenesis, frequently in a central position from which the process of transformation spreads, until the whole skeleton is ossified. The appearance of such centres of ossification is spread over a long period of time. A large number are seen first in embryonic life, some appear much late in prenatal life and others appear after birth.The earliest centres of ossification appear at the end of 2nd month of pregnancy. At the 11th IU week there are 806 centres, at birth around 450. 73
  75. 75. II. ROLE OF DENTAL TEAM IN MASS FATALITY INCIDENTS  Dental team has a major part in resolution of mass fatality incidents.  Definitions: Disaster:A disaster is a sudden occurrence that exceeds the resources available in a community to deal with it. Mass fatality incident: A mass fatality incident is an occurrence that causes loss of life that exceeds death investigation resources in a community Team work and planning are two overlying principles crucial to disaster management. Dental team preplanning for mass fatality incidents includes training, formal agreements with a medical examiner, supply sources and immunization. An incident command system is used to coordinate the activities of the many responders to promote the teamwork 75
  76. 76.  An incident command system is used to coordinate the activities of the many responders to promote the teamwork needed for an effective incident response.  Important aspects of mass fatality incident management are preparing post mortem and ante mortem records, using computer programs and imaging.  The dental identification can be divided into several different sections based on its missions including recovery, post mortem examination, ante mortem records and comparison. (i) RECOVERY TEAM: The recovery team assists in recovery of remains on site, if called for in the disaster protocol. 76
  77. 77. (ii) POST MORTEM SECTION: The postmortem section is responsible for complete analysis of all post mortem evidence.This analysis includes examination of all dental structures, photographic documentation of the remains as received, reconstruction and stabilization of fragmented or burned remains and a complete charting and documentation of all restorations, anomalies and injuries evident on the dental structures recovered. (iii) COMPARISON SECTION: The comparison section compares ante mortem and post mortem charts and radiographs and provides recommendations through the dental section leader to the identification center chief on identification of the victims. (iv) COMPUTER SECTION: Computer section assists in matching ante mortem and post mortem data by using specialized softwares. 77
  78. 78. DENTAL IDENTIFICATION TEAM ORGANIZATIONS FOR MASS FATALITY INCIDENTS:  There are 2 types of dental identification teams. A)Traditional Identification Team:  It is a community based / state based identification team.  Team members include dentists, hygienists and dental assistants. B) Disaster Mortality Operational Response team (DMORT):  The DMORT is a part of the national disaster medical system under the US department of public health.  The DMORT team consists of a dental team, forensic pathology team, anthropology, laboratory support, photographic and communication support, logistics team and mortuary science team. 78
  79. 79. Bite marks 79
  80. 80. BITE MARK EVIDENCE  Definition  History  Description  Classification  Factors influencing bitemarks  Analysis
  81. 81. INTRODUCTION  Bitemark >>>> ‘Patterned injury’  Bitemark >>>> ‘Tool-mark’  Bitemark evidence admissible under Frye test (Recognizable, Established & Acceptable - Scientific evidence)
  82. 82. DEFINITION OF BITEMARK  A representative pattern left in an object or tissue by the dental structures, either alone or in combination with other oral structures of an animal or human  Physical alteration in a medium caused by the contact of teeth  A mark made by the teeth either alone or in combination with other mouth parts (Mc Donald)  Cutaneous human bitemark = Injury in skin caused by contacting teeth (with or without the lips or tongue), which shows the representational pattern of the oral structures
  83. 83. DEFINITION OF BITEMARK  Given by Jakobsen : - Bitemark =Tooth marks produced by antagonistic teeth Tooth mark = Mark left by a tooth Arch mark = Mark produced by four or five adjacent teeth in the same arch Given by Mac Donald : as “a mark caused by the teeth either alone or in combination with other mouthparts”.
  84. 84. HISTORY OF BITEMARKS  William the Conqueror validated royal documents by biting into wax seal  ‘Indentured’ servants from Britain or Europe  Earliest recorded bitemark case in U.S. - Ohio vs. Robinson (1870)  First recorded instance where expert guidance was given (1906) – Bitemarks in cheese  First investigator of bitemarks : Sorup (1924)  First case involving admissibility of bitemark evidence : Doyle vs. Texas State (1954)  First case involving bitemark that led to conviction : 1972 rape case, Illinois vs. Johnson
  85. 85. DESCRIPTION OF BITEMARK Prototypical Human Bitemark = • Circular/oval patterned injury • Two opposing symmetrical, U-shaped arches • Separated at their bases by open spaces • Diameter of the injury = 25-40 mm • Central area of bruising (extra vascular bleeding caused by pressure from teeth as they compress the tissue inward from the perimeter of the mark) • Periphery of the arches : Series of individual abrasions, contusions and / or lacerations reflecting size, shape, arrangement & distribution of the class characteristics of the contacting surfaces of the human dentition
  86. 86. DESCRIPTION OF BITEMARK (continued)  Inflicted slowly & deliberately  Suction to tissue by tongue & lips  Central or peripheral ‘suck-marks’  Anterior teeth marks with good definition Sexually Oriented bitemark = Self Inflicted Bitemarks =  More on forearms of children  Mentally retarded or psychologically disturbed people  Lesch – Nyhan Syndrome (X-linked, recessively transmitted disease)
  87. 87. DESCRIPTION OF BITEMARK Pressure exerted while biting  Incisors = 11 Kgs.  Tongue = 8 lb/sq. in.  Tongue negative suction = 20 mm Hg Location of bitemarks on skin  Vale et al : Arms > Breasts > Legs > Abdomen > Back > Face > Shoulder > Buttocks > Female genitalia > Hand > Chest > Neck > Nose > Male genitalia > Ear > Foot  Vernon Geberth : 1. Homosexual homicides : Back, arms, shoulders, face, and scrotum of victim. 2. Heterosexual aggression : Breast & thigh 3. Battered children : Randomly placed
  88. 88. CLASSIFICATION OF BITEMARKS According to agents causing bitemarks : - 1. Human bitemarks : Adults, Children 2. Animal bitemarks : Mammals, Reptiles, Fish 3. Mechanical bitemarks : Dentures, Saw-blade According to substrate in which bitemarks are made 1. Bitemarks in Skin & body tissues 2. Bitemarks in Food substances 3. Other materials
  89. 89. CLASSIFICATION OF BITEMARKS Based on severity of injury  Hemorrhage : Small bleeding spot  Abrasion : Undamaging mark on skin  Contusion : Ruptured blood vessel, bruise  Laceration : Punctured or torn skin  Incision : Neat puncture of skin  Avulsion : Removal of skin  Artifact : Bitten-off piece of body Based on degree of impression  Clearly defined : Significant pressure  Obviously defined : First-degree pressure  Quite noticeable :Violent pressure  Lacerated : Skin violently torn from body
  90. 90. CLASSIFICATION OF BITEMARKS Dr. Lowell Levine’s Classification : -  Slowly inflicted bite : Show a ‘suck mark’ area with an abrasion pattern that resembles a sunburst  Attack/Defensive bite : No clear pattern and difficult to identify
  91. 91. CLASSIFICATION OF BITEMARKS Webster’s classification of bitemarks in inanimate objects  Type-1 : - Prominent incisal edges recorded; Ex. – Chocolate  Type-2 : - Labial aspect of incisors & scrape marks recorded; Ex. – Apple  Type-3 : - Relative position of upper & lower teeth in centric occlusion recorded; Ex. – Cheese
  92. 92. 2. CLASSIFICATION OF BITE MARKS: I. CAMERON AND SIMS CLASSIFICATION: This is based on the type of agent producing the bite mark and the material exhibiting it. i) Agents ii) Materials Human - Skin, body tissue Animal - Food stuff - Other materials II. MAC DONALD’S CLASSIFICATION: Mac Donald suggested an etiological classification.This is pertinent to human bitemarks. 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 / occlusal surfaces of teeth. 93
  93. 93. ii)Tongue pressure marks: When sufficient amount of tissue is taken into the mouths, the tongue presses it against rigid areas such as lingual surfaces of teeth and palatal rugae.The marks thus left on the skin are referred to as ‘sucking’. Since there is a combination of sucking and tongue thrusting involved. iii)Tooth scrape marks: These are marks caused by scraping of teeth across the bitten material.They are usually caused by anterior teeth and present as scratches or superficial abrasions. iv) Complex marks: Combination of above types of marks 94
  94. 94.  Bite marks are usually associated with sex crimes, violent fights, child abuse and thefts, etc.  CRIMES INVOLVING BITE MARKS: 95 (i) Assault cases (Adult) (ii) Abuse cases (Children) a)Non Sexual a) Multiple Incidents - Healed - Healing - New b) Sexual - Forcible - Voluntary - Homosexual - Heterosexual b) Single Incident - New injuries only - Adult perpetrator - Child perpetrator
  95. 95. FACTORS INFLUENCING BITEMARKS  Type of tissue  Age  Sex  Medical status  Time  Force exerted  Number & type of teeth  Presence of tongue thrust  TMJ problems
  96. 96. ANALYSIS OF BITEMARKS Description of bitemark Collection of evidence from victim Collection of evidence from suspect Evaluation of evidence
  97. 97. DESCRIPTION OF BITEMARK 1. Demographics 2. Location of bitemark 3. Shape of the bitemark 4. Color 5. Size 6. Type of injury 7. Other information
  98. 98. COLLECTION OF EVIDENCE FROM VICTIM 1. Photography 2. Impressions 3. Salivary swabbing 4. Tissue samples
  99. 99. COLLECTION OF EVIDENCE FROM SUSPECT 1. History 2. Photography 3. Extra-oral examination 4. Intra-oral examination 5. Salivary swabbing 6. Sample bites 7. Impressions & Study casts
  100. 100. EVALUATION OF EVIDENCE  ABFO Scoring Sheet for Bitemark Analysis (Gross features,Tooth position, Intra-dental features)  OdontometricTriangle method  Comparison techniques : - 1. Direct methods 2. Indirect methods
  102. 102. PHYSICAL COMPARISON  Transparent Overlay =Transparent film with edges of teeth which can be superimposed on bitemark injury / photographic evidence  Methods of Overlay fabrication: - 1. Direct Cast Tracing 2. Wax Imprints method 3. Radiography method 4. Xerography method 5. Computer based method 6. Photography method
  103. 103. DIRECT CAST TRACING METHOD Sticky-wax Glass-slab
  104. 104. WAX IMPRINTS METHOD ( Luntz & Luntz )
  107. 107. COMPUTER BASED METHOD Adobe Photoshop ® Software
  110. 110. IV. RECOGNITION AND REPORTING OF DOMESTIC VIOLENCE, ABUSE AND NEGLECT  Physical abuse is characterized by the infliction of physical injury as a result of punching, beating, kicking, biting, burning, shaking or otherwise harming a child.The parent or caretaker may not have intended to hurt the child, the injury may have resulted from over discipline or physical punishment.  Child neglect is characterized by failure to provide for the child’s basic needs. Neglect can be physical, educational or emotional. Rampant caries may be considered child neglect.  Sexual abuse includes fondling a child’s genital, intercourse, incest, rape, sodomy, exhibitionism and commercial exploitation through prostitution or the production of pornographic materials. 116
  111. 111. i) RECOGNIZING CHILD ABUSE AND NEGLECT:  According to statistics, 50-65% of all physical trauma associated with abuse occurs in the head, face or neck.  Head Skull Bald spots (traumatic alopecia) Bruises behind ears (Battle’s sign)  Face Eyes Retinal haemorrhage Blackened eyes (Racoon eyes) 117
  112. 112.  Nose Fractures Displacement  Lips Bruises Lacerations Angular abrasions (gag marks)  Intra oral Frenum tears Palatal bruising (forced fellatio) Residual tooth root  Maxilla / mandible Fractures or improperly healed fractures Malocclusion from previous fractures 118
  113. 113.  Teeth Fractured, mobile, avulsed or discoloured teeth in the absence of reasonable explanations Untreated rampant caries Untreated, obvious infections or bleeding  Interviewing the possible victim:  Recognizing the abuse is the first and earliest step in the process.  Asking probing questions to a young child about the behaviour of a parent or caregiver is stressful.The interview should be conducted in private.  The child should be asked if he / she feels safe at home or in the care of a care giver and whether the injuries were caused intentionally and by whom. 119
  114. 114.  Permission should be sought to photograph suspicious injuries. Any injury should be documented carefully. Injury diagram and photographs may be valuable tools for possible future litigation.  Reporting possible Abuse of neglect:  Individuals typically designated as mandatory reporters include physicians, nurses, hospital personnel, dentist, medical examiners, coroners, mental health professionals, social workers, school personnel, Law enforcement officials and child care providers.  Any person may report incidents of abuse or neglect however.  Reports should be made to the state child protective service agency. 120
  115. 115.  Prevent abuse and neglect through Dental Awareness (PANDA) coalition is a public private partnership committed to educating dental professionals on how to recognize and report suspected cases of child abuse. 121
  116. 116. ii) DOMESTIC VIOLENCE, INTIMATE PARTNER VIOLENCE, SPOUSAL ABUSE AND BATTERED WOMEN:  Spousal abuse, also termed intimate partner violence (IPV) is violent behaviour occurring between partners in an intimate relationship regardless of their marital status.  The battered women syndrome has been defined as a symptom complex occurring as a result of abusive actions directed against a woman by her male partner.  Most definitions of IPV emphasize the physical abuse component because of the severe physical injuries that may occur but, the health care provider should be aware of the mental abuse and intimidation are integral components of the abuse syndrome. 122
  117. 117.  Physical injuries often seen in non accidental trauma may include soft and hard tissue injuries of the maxilla facial complex. Fractures of nasal bones, jaws, orbital structures and zygomatico maxillary complex are common in battered women. Fractures, avulsed or subluxated teeth also can be indicators of non accidental trauma. Lacerations and contusions of the facial soft tissues can be seen.  Not withstanding valuable information gained from the physical examination, the patient history can be an equally important indicator of abuse.  Patients with a positive history screen for domestic violence should be documented in the permanent medical record. A suspected victim of non accidental trauma should be interviewed in a private setting because the abuser often tries to remain close to the victim, answering questions that are directed to the victim. 123
  118. 118.  Every dentist should be aware of state requirements for reporting domestic violence in all its various forms. 124
  119. 119. iii) RECOGNITION OF ELDER ABUSE AND NEGLECT:  The concept that neglect is less damaging and less likely to cause injury or impairment of the elderly individual is not always true. Active neglect (intentionally denying or withholding care) and passive neglect (unintentionally failing to provide care) can be equally damaging to the aged person. The emotional and psychological consequences of all forms of mistreatment can be life threatening. In some cares, active neglect can be so damaging that it leads the older person to long for death.  Physical abuse generally is associated with other forms of mistreatment such as financial exploitation, verbal or emotional abuse or active neglect.  Physical abuse is always considered to be criminal behaviour regardless of extenuating circumstances. 125
  120. 120.  Like child abuse, most of the injuries in other forms of domestic violence are found in the head and neck area, visible to the dental team.  The signs and symptoms of elder abuse and neglect sometimes are subtle, but careful observation followed by sensitive and cautious questioning can optimize accurate diagnosis.  Signs and symptoms of elder abuse / neglect includes contusions, abrasions lacerations or cuts on the head, face and neck and exposed areas of arms and legs, lip trauma, fractured or subluxated teeth, fractured maxilla or mandible, bite marks, lack of adequate dental care and lack of adequate dental care and lack of adequate dental care and lack of adequate nutrition.  A comprehensive and valid history combined with a thorough head, neck and oral examination is essential in forming a differential diagnosis regarding the cause of skin and mucosal lesions. 126
  121. 121. Reporting Elder abuse:  If any member of the dental team, especially the dentist, suspects that the patient is a victim of intentionally inflicted trauma, specific actions should be taken.The suspected victim of abuse should be interviewed in a supportive, non accusatory manner.The examiner or recorder should document all patients statements regarding the history of abuse in patients own words.  In elder abuse cases, documentation of the injury patterns is important. Photographs and a diagram if possible should be taken.  Radiographs are essential in the diagnosis and appropriate treatment of maxillofacial trauma. Evidence of features at various stages of healing and missing teeth in the absence of periodontal disease can be evidence of repeated assaults. 127
  122. 122. V. MALPRACTICE 128
  123. 123. V. MALPRACTICE  The word malpractice means wrong doing / neglect of duty.  Malpractice is, dishonest use of a position of trust for personal gain. TYPES OF MALPRACTICE CASES: This list is given in order of frequency 1. Paresthesia or Anesthesia There are usually associated with the removal of lower third molars and bicuspids as well as occur following endodontic treatment. Poor techniques and / or inadequate radiographs are often encountered. 129
  124. 124. 2. Failure to diagnose: Failure to take a complete medical and dental history, to complete a thorough oral examination, take quality radiographs, study models, written records of diagnosis, treatment plans. Pulp vitality testing is often omitted for teeth involved in major reconstruction cases. 3. Improper diagnosis: These cases often imply the dentist has not taken advantage of continuing education courses available. He still relies on the education obtained in dental school and is not keeping abreast with up to date knowledge concerning the profession. 4. Failure to refer: Many dentists frequently attempt to do services for patients that are beyond their limits of skill, training experience and expertise. 130
  125. 125. 5. Failure to inform: The patient must be adequately informed as to what his dental problems are, what results and limitations of proposed treatment can be expected and what financial investments he will incur for these services. Alternative methods of treatment and the consequences of no treatment must be explained. It behooves every dentist to thoroughly inform his patients when there is a broken instrument, fractured root tip or endodontic instrument, foreign bodies in sinuses, air emphysema or severance of nerves and vessels.This must be documented by radiographs as well as written records. 6. Removal of wrong tooth: This problem is often a result of poor communication between the referring dentist and the oral surgeon. 7. Denture problems: Frequently this is really a communication problem between the patient and the dentist. Often the dentist does what is technically correct but does not understand the patient’s desires.The patient often has unrealistic expectations. 131
  126. 126. 8. Negligent deaths: There is little or no excuse for not taking and recording a complete health history. Proper management of the medically compromised or high risk patient first requires that the patient be identified by health history, drug history, physical examination and / or medical consultation. Full documentation in the dental record, appropriate modifications in treatment procedures an advance emergency planning are required, including emergency drugs and training of personnel in CPR. DEFENCE INTHE MALPRACTICE SUIT: It would be beneficial for the dental profession to take more preventive attitude. 1)Try to provide above average dental care, be fully aware of the probable increase in the legal standard of care. 2) Keep accurate, legible written records. 3) Complete the written record in the presence of patient. 132
  127. 127. 4) Never add to or alter records. 5) Keep abreast of changes within the profession through publications and continuing education courses. 6) Be ware of your legal responsibilities to patients. Determine their dental expectations and obtain adequate consent before delivery of treatment. 7) Utilize radiographs both pre operatively and post operatively. They not only serve as a diagnostic tool, but function as an outstanding record as well. 8) Keep professional confidence of patients strictly privileged. 9) Make appropriate financial arrangements and never guarantee results. 10) Be aware of oral changes suggestive of disease. 11) Advise patients of any absence from practice. Recommend a competent, available substitute dentist. 133
  128. 128. 12) Establish and maintain rapport with your patient. 13)Take thorough medical histories. 14) Keep all promised appointments. 15)Avoid diagnosis and prescribing by phone. 16) Refrain from utilizing unapproved or experimental procedures. Avoid fields where you are not properly qualified. 17) Select, train and properly utilize dental auxillaries within the parameters of your state laws. 18) Be familiar with manufacturers warnings of possible adverse drug reactions. 19) Have an attorney review your liability insurance policy to determine whether or not the company can arbitrarily settle your case out of court. 134
  129. 129. 135 VI. LIP PRINTS
  130. 130. VI. LIP PRINTS  Tsuchihashi named the wrinkles and grooves visible on the lips as ‘sulci labiorum rubrorum’.The imprint produced by these grooves is termed ‘lip print’, the examination of which is referred to as ‘cheiloscopy’. These grooves are heritable and are supposed to be individualistic. Lip prints therefore, can constitute material evidence left at a crime scene, similar to finger prints. LIP PRINTS WERE FIRST CLASSIFIED BY SANTOS AS: 1) Simple wrinkles:  Straight line  Curved line  Angled line  Sine shaped curve 136
  131. 131. 2) Compound wrinkles:  Bifurcated  Trifurcated  Anomolous TSUCHIHASHI‘S CLASSIFICATION: Type – I : Clear cut vertical grooves that run across the entire lip Type – II : Similar to type I, but do not cover the entire lip Type – III : Branched grooves Type – IV : Reticular grooves Type –V : Grooves that cannot be morphologically differentiated 137
  132. 132. 138 TYPE – IV :RETICULAR GROOVES Type – III : Branched grooves
  133. 133. Type – V : Grooves that cannot be morphologically differentiated 139
  134. 134.  DISADVANTAGES OF LIP PRINT INVESTIGATIONS ARE: 1) Uncertainty about the persistence of lip patterns.Trauma, pathosis, surgery can affect the size and shape of the lip. 2) Anatomic position of lip roves on the zone of transition close to the vermilion border is extremely mobile. Consequently, the prints produced may differ in appearance depending upon the pressure applied and its direction. 140
  136. 136. VII. THE PALATAL RUGAE IN IDENTIFICATION  Identifying individuals from their teeth, either by comparison with antemortem dental records or DNA samples is impractical in identifying edentulous individuals. A method developed of identifying such individuals is by examining the palatal rugae pattern.  The rugae pattern on the deceased’s maxilla or maxillary denture is compared to old dentures that may be recovered from the decedent’s residence, or plaster models that may be available with the treating dentist.  Palatal rugae are ridges on the anterior part of palatal mucosa on each side of the mid palatine raphae, behind the incisive papilla. Palatal rugae are well protected by the lips, cheek, tongue, buccal pad of fat and teeth in incidents of fire and high impact trauma. 142
  137. 137.  Rugae pattern in unique to an individual.They do not change shape with age and reappear after trauma or surgical procedures. CLASSIFICATION OF PALATAL RUGAE:  Lysell, measured rugae in a straight line, from their origin on the medial side to terminus at the lateral and categorized them into: 1) Primary rugae (> 5 mm) 2) Secondary rugae (3-5 mm) 3) Fragmentary rugae (2-3 mm)  (Rugae < 2 mm is not taken into consideration).  Thomas and Kotze gave details of various patterns of primary rugae.These include branched, unified, cross linked, annular, papillary. 143
  138. 138.  ANALYSIS OF RUGAE PATTERNS:  Thomas andVan Wyk have manually traced rugae patterns on to clear acetate and then super imposed these tearings on photographs of plaster models.  On digitized images of the palate, characteristic points are plotted on the medial and lateral extremities of all the rugae.  The plotted points are processed by the software and in information sequentially stored corresponding to pixel position.This is compared with ante mortem records. 144
  140. 140. VIII. CLASSIFICATION FROM DENTAL DNA  The conventional method of dental identification requires adequate / complete dental records that may not always be available.  Polymerase chain reaction (PCR) allows amplification of even highly degraded DNA.  This facilitates comparison with a known biological ante mortem sample of the decedent, such as hair from a hair brush, epithelial cells from a tooth brush or a biopsy specimen.  A major advantage of DNA analysis over conventional dental identification is that if a decedent’s ante mortem sample is unavailable, the DNA pattern may be compared to a parent or to a sibling thus allowing identification. 146
  141. 141. EXTRACTION OF DENTAL DNA  Owning to its neuro vascular nature, pulpal tissue is considered to be the best source of dental DNA. Sweet & Hidebrand have advocated a method known as cryogenic grinding for extracting DNA.  This involves cooling the whole tooth to extremely low temperatures using liquid nitrogen and then mechanically grinding it to fine powder.  Using standard protocols, sufficient amount of DNA can be obtained from intact, carious, as well as root filled teeth. Extraction of DNA can be done from pup and hard tissues such as dentin and cementum.  The major drawback of cryogenic grinding is that the tooth needs to be completely crushed. 147
  142. 142.  Trivedi and coworkers have suggested a less destructive method for DNA isolation.  These method involves drilling of the root canals, scraping the up area with a notched medical needle and subsequent flushing of the tissue debris.This method will save the morphology of tooth  TYPES OF DNA:  Pretty and Sweet have pointed out the use of two types of DNA.  The first is called genomic or nuclear DNA.This is located in the nucleus of the cells and is commonly used in forensic cases.  The second, known as mitochondrial DNA (mt DNA), is present in the mitochondria of cells. 148
  143. 143.  A major advantage of mt DNA is that each cell has a high copy number of mt DNA, Eg: Epithelial cells contain 5000 mt DNA molecules.  Hence, mt DNA can substitute in cases where nuclear DNA is unavailable.  Also, mt DNA is exclusively inherited from the mother i.e., there is no contribution whatever from the father.  Thus, an identical mt DNA pattern is observed among siblings, their mother and many maternal relatives.  Moreover, due to their exclusive maternal inheritance.They can be used to establish identity in cases where there is a gap of several generations. 149
  144. 144. Conclusion:  Because of the high percentage of physical abuse that occurs to the head, face and neck regions in all age groups, it is important for members of the dental profession to recognize the signs and symptoms of abuse, to understand the obligation to report, and to know the mechanism for reporting.The recognition and reporting of neglect is equally important. Many individuals can be spared pain, suffering and death by timely intervention after observations made in a dental setting. 150
  145. 145. 151 FOR NOT SLEEPING Thank you