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IDENTIFICATION
Identification through bodily features
It is the determination of the individuality of a person based on certain physical characteristics i.e. exact fixation of personality. It is necessary in case of:
1. Living persons
2. Recently dead persons
3. Decomposed bodies
4. Mutilated bodies
5. Skeleton
In all medico-legal cases atleast 2 indentification marks should be noted.
Corpus Delicti: It is the body of offence; the essence of crime. It means the facts of any criminal offence, e.g. murder. The corpus delicti of murder is the fact thata person died from unlawful violence. It includes:
1. Body of victim
2. Other facts; bullet
3. Broken knife blade found in the body
4. Clothings showing marks of weapons
5. Drawings of photographs and deceased showing fatal injuries
Or other facts which are conclusive of death by foul play. The main part of corpus delicti is the establishment of identity of dead body and infliction of violence in a particular way, at a particular time and place, by the person or persons charged with the crime and none other.
RACE
SKELETON : Cephalic index is important.
CI: (Maximum breadth of the skull/maximum length of the skull)X 100
Length and breadth are measured by using calipers between both parietal eminences and b/w glabella and external occipital protuberance.
Racial difference in the skull
Type of skull C.I Race Dolico-cephalic (long headed) 70-75 Pure Aryans,aborigines and negroes
Mesati-cephalic (medium headed) 75-80 Europeans and chinese
Brachy-cephalic (short-headed) 80-85 Mongolian
Brachycephaly is due to the fusion of coronal suture.
Skull differentiation into 3 races:
Caucasian(white) Mongolian (yellow) Negro (black) Skull Round Square Narrow & elongated Orbits triangular Rounded Square Nasal aperture Elongated Rounded Broad Palate Triangular Rounded Rectangular Upper & lower limbs Normal in proportion to the body
Smaller in proportion to the body
Longer in proportion to the body
Indian skull is Caucasian with a few negroid characters.
Mongoloids: nativeamericans, Asiatic orientals like Koreans, Japanese, Chinese and south east Asians.
Sex
Sex chromatin: It is a planoconvex mass lying near the nuclear membrane (barr body)- demonstrated by Dixon &Tarr.
Males: In buccalsmear ,0 to 4% nuclei containing chromatin body
Davidson body is absent in males.
Females : 20 to 80% nuclei containing barr body
Neutrophil leucocytes contain Davidson body ( small nuclear attachment of drumstick form)
• Exact sex determination: single specimen of buccal smear, saliva or hair follicle by the combined treatment of
quinacrinedihydrochloride staining for Y-chromosome , seen as bright fluorescent body in nuclei of male cells.
• Quinacrine positive bodies : 45-80% in males & 0-4% in females
• Fluorescent feulgen reaction using acriflavin Schiff reagent for X chromosomesas bright yellow spot in the nuclei.
• Fluorescent bodies : 50-70% of cells in females & 0-2% in males.
• By using fluorescent dyes Y chromosome can be demonstrated in the dental pulp tissue upto 1 year.
• Karyotyping of the foetus can be done from lymphocytes, amniocytes and fibroblasts.
INTERSEX • Intermingling in one individual of characters of both the sexes in
varying degrees,including physical form, reproductive organs and sexual behaviour.
• Results from defect in embryonic development.
Divided into 4 groups:
1. Gonadal agenesis • Testes or ovaries have never developed.
• Nuclear sex is negative.
2. Gonadal dysgenesis • External sexual structures present
• At puberty testes or ovaries fail to develop.
• Divided into 2:
i. Klinefelter’s syndrome • Anatomical structure is male
• Nuclear sexing is female (XXY 47 chromosomes)
• Delay in the onset of puberty, behavioural disorders & mental
retardation
• Axillary & pubic hair absent, hair on chest, chin are reduced
• Gynaecomastia , azoospermia, sterility, increased height
ii. Turner’s syndrome • Anatomical structure is female.
• Nuclear sexing is male.(XO 45)
• Recognised at birth with the edema of the dorsum of hands & feet
• loose skin folds in the nape of the neck & short stature.
• Webbed neck
• Lack of development of primary & secondary sexual characters.
• Cushing’s syndrome & high incidence of diabetes mellitus, ovarian
dysgenesis.
3. True- Hermaphroditism • Very rare condition of bisexuality.
• Sex chromatin maybe male or female.
• In this an ovary & a testicle or 2 ovotestis are present with the external
genitalia of both sexes.
• Gonad may be abdominal, inguinal or labio-scrotal in position.
• There may be uterus, Phallus may be penile or clitoral.
• Labia- bifid as in female or fused resembling the scrotum of the male.
• Neither gonad is completely functional.
4. Pseudo-hermaphroditism • Gonadal tissues of only one sex seen internally
• External appearance is of opposite sex.
• Two types:
i. Male
pseudohermaphroditism
• Nuclear sex is XY.
• Sex organs & sexual characteristics deviate to female form.
• Testicular feminisation.
ii. Female
pseudohermaphroditism
• Nuclear sex is XX.
• Deviation of sex organs & sexual characters towards male.
SYMPHYSIS PUBIS:
▲ The best single criterion for determining age from third to fifth generation.
▲ Require bones that are free of cartilage.
▲ Surface features blurred if there is erosion by drying and damage.
▲ 20 years- markedly irregular or uneven, ridges run transversely across articular surface.
▲ 24 to 36 years – ridges gradually disappear, surface has a granular appearance, ventral (outer) and dorsal (inner) margins
completely defined.
▲ Early in the fifth decade – symphysial face – oval, smooth surface, raised upper and lower ends.
▲ Towards end of 5 th^ decade – narrow beaded rim develops on the margins.
▲ 6 th^ decade – erosion of surface, breakdown of ventral margin begins.
▲ 7 th^ decade- surface irregularly eroded.
STERNUM:
▲ 14 to 25 yrs- 4 pieces of the body of the sternum fuse with one another from below upwards
▲ 40 yrs- xiphoid unites with body
▲ Old age- manubrium fuses with body.
RIBS:
▲ Progressive ossification of sterna rib ends of the coastal cartilages correlate with increasing age within 5-8 yrs of real age.
HYOID BONE:
▲ 40-60YRS – greater cornu of the hypoid bone unites with the body.
SKULL:
Bones of calvaria(8) : parietal(2) ,
frontal(1) ,
temporal(2) ,
occipital(1),
Sphenoid(1),
Ethmoid(1) Bones of face and jaws(14) : Maxilla-
Zygomatic-
Nasal-
Lacrimal-
Palatine-
Inferior nasal concha-
Mandible-
Vomer-
▲ lateral and occipital fontanelles close within first 2 months
▲ posterior fontanelle – closes in 6-8 months
▲ anterior fontanelle – closes- 1.5 – 2 years
▲ 2 years- two halves of mandible unites.
▲ 3 rd^ year- condylar portions of occipital bone fuse with squama, 5th^ year- with the basioccipital bone.
▲ 3 rd^ yr – metopic sutures closes
▲ Lapsed union – ectocranial suture closure variable- may not be a closure.
SACRUM:
▲ 5 sacral vertebrae are separated by cartilage until puberty, when lateral portions grow together.
▲ After this, fusion of epiphysis takes place and ossification of invertebral disc extends from below upwards.
▲ 21-25 yrs- sacrum becomes a single bone
SCAPULA:
▲ 30-35 yrs- lipping starts on ventral margins of glenoid cavity
▲ 35- 40 yrs- irregular lipping around clavicular facet and inferior surface of acromion process.
▲ 50yrs- cristae scapulae
Age Appearance of centre of ossification Union of bone and epiphysis.
5 thyr Head of radius, trapezoid , scaphoid. Greater tubercle fuses with head of humerus
6 thyr Lower end of ulna Rami of pubis and ischium unite
6 th-7 thyr Medical epicondyle of humerus
9 thyr Olecranon
9 th^ – 11 thyr Trochlea of humerus
10 th^ – 11 thyr Pisiform
11 thyr Lateral epicondyle of humerus
13 thyr Separate centres in triradiate cartilage of acetabulum
12 th^ to 14 thyr Lesser trochanter of femur 14 thyr Crest of ilium , head and tubercles of ribs
Medical epicondyle of humerus: lateral epicondyle with trochlea , patella complete.
15 thyr Acromion^ Coracoids with scapula; triradiate cartilage of acetabulum
`16 thyr Ischial tuberosity Lower end of humerus; olecranon to ulna , upper end of radius , metacarpals, proximal phalanges
17 th^ – 18th^ Head of femur , lesser and greater trochanter of femur , acromion , lower end of ulna
18 th-19 thyr Inner end of clavicle^ Lower end of femur , upper end of tibia , and fibula, acromion , lower end of ulna
20 th-21 styr Iliac crest , inner end of clavicle ; ischial tuberosity, head of ribs.
Some definitions related to bones
Bone Markings / Features on Bones
Bone markings and the features of bones (including the correct words used to describe them) are often required by first-level courses in human anatomy and associated health science subjects. It is important to be familiar with the terminology used to refer to bone markings in order to communicate effectively with professionals involved in healthcare, research, forensics, and related disciplines.
The following terms used to describe bone markings or features on bones are in alphabetical order with short definitions:
Word / Term (Bone Marking or Feature)
Meaning / Description Type of bone marking
Example(s)
- Angle A corner Feature of shape of bone
Inferior angle (lower) and superior angle (upper) are the rounded angles or "corners" of the scapula.
- Body The main portion of a bone The diaphysis of long bones such as the humerus.
- Sinus Cavity within a bone Cavity The sphenoidal sinuses are the semi-open areas enclosed by the sphenoid bone that act as drains from the nasal cavity.
- Spine or Spinous process
Similar to a crest but raised higher; a sharp, pointed, slender projection. Such sharp raised projections called spines are often sites for muscle attachment.
Process - attach connective tissues
The spinous processes of vertebrae , which together form the "spine" (backbone).
- Sulcus ( pl. sulci)
Groove, crevice or furrow. Such elongated depressions may accommodate a blood vessel, nerve or tendon.
Channel-like depression
Sigmoid sulcus on the inner surface of the mastoid portion of the temporal bone(s) - which form part of the skull (behind the ears).
- Trochanter Large blunt bump-like projection (larger than a tuberosity, which is in turn larger than a tubercle)
Process - attach connective tissues
Only one human example: the greater trochanter at the top of the femur (bone), upper-leg.
- Tuberosity Large rounded or oblong projection that may look like a raised bump. Such rounded/ oblong projections called tuberosities are often sites for muscle attachment.
Process - attach connective tissues
The deltoid tuberosity of the humerus (bone), upper-arm.
- Tubercle Small tuberosity that may also be described as a round nodule or warty outgrowth.
Process - attach connective tissues; can also form articular surfaces
The non-articular part of each rib tubercle attaches to the ligament of the tubercle.
Note: This table lists bone markings and features on bones in alphabetical order. It is a numbered list because some people find it easier to remember sets of information by also remembering how many of each type of item they have to recall.
TEETH
Tooth – crown + neck + root(embedded in the jaw bone)
Teeth- composed of dentin , covered on crown by enamel , on root by cementum , which is attached to alveolar bone by periodontal membrane.
INCISORS: crown shaped like chisel , convex on its labial surface , except near neck , neck slightly constricted. Root is single
CANINES: larger than incisors , crown large and conical , very concave on its surface. Masticatory edge tapers to a blunt point. Root-single , larger and thicker.
PREMOLARS (bicuspids) : smaller and shorter than canines, crown circular in cross-section , slightly compressed mesio- distally. Chewing surface – two cusps Root single or maybe double.
MOLARS: largest, broad crown , cubical crown , convex on its labial surface , flattened on its mesial and distal surface. Three, four ,or five cusps. Upper molar- three roots , lower molar – two roots.
DECIDUOUS TEETH: resemble in the form the teeth bear same names in permanent set.
TEMPORARY (deciduous , milk )TEETH – 20 in number
Incisors-4 , Canines-2 , Molars-4 (in each jaw)
4 th^ yr- spacing b/w deciduous teeth
6 th^ or 7thyr- first permanent molar teeth erupt behind temporary molars.
after this – temporary teeth begin to fall off.
7-12 yr – 24 teeth present
Age 9- 12- permanent teeth in mouth(8 incisors and 4 first molars)
Age 14- no deciduous teeth , 28 permanent teeth in mouth.
PERMANENT TEETH – 32 in number
Incisors-4 (in each jaw)
Canines- 2 ( “ )
Premolars-4 ( “ )
Molars-6 ( “ )
Trait Temporary teeth Permanent teeth
- Size Smaller , lighter , narrower , except temporary molars which are longer than permanent premolars replacing them.
Heavier , stronger , broader , except permanent premolars replacing temporary molars.
- Direction Anterior teeth are vertical Anterior teeth inclined forward 3.crown China white Ivory white
- Neck More constricted Less constricted
- Root Smaller , more divergent Larger , less divergent
- Ridge A ridge or thick edge at the junction of crown with fangs is present
Ridge is absent
TOOTH
Tooth Calcification begins Eruption Calcification completed
Resorption of root begins
- Central insicor
5-6 months(lower)
“ (upper)
6-8 months(l)
7-9 months(u)
1.5-2yrs (l)
“ (u)
4 thyr (l)
5 thyr(u)
- Lateral incisor Same as above 7-9 months(u)
10-12 months(l)
1.5-2 yrs (l and u) 5 thyr ( u and l)
- First molar Same as above 12-14 months 2-2.5 yrs 6 thyr
- Canine Same as above 17-18 months 2.5-3 yrs 8 thyr
- Second molar Same as above 20-30 months 3 yrs 7 thyr
CALCIFICATION AND ERUPTION OF DECIDUOUS TEETH
TOOTH CALCIFICATION
BEGINS
ERUPTION CALCIFICATION
COMPLETE
First molar At birth 6-7 yrs 9-10 yrs Central incisor 3-4 months 6-8 yrs 10 yrs Lateral incisor 1 yr 7-9 yrs 11 yrs First bicuspid 1.5 yrs 9-11 yrs 12-13 yrs Second bicuspid 2 yrs 10-12 yrs 12-14 yrs Canine 4-5 months 11-12 yrs 12-13 yrs Second molar 2.5-3 yrs 12-14 yrs 14-16 yrs Third molar 8-10 yrs 17-25 yrs 18-25 yrs
CALCIFICATION AND ERUPTION OF PERMANENT TEETH
IMPACTED TEETH- molars do not erupt due to lack of space in the jaw, such teeth are trapped. (Mandibular third molars).
All teeth – visualized by x-ray by dental panoramic tomography (orthopantogram)
GUSTAFSON’S METHOD – age estimate over 21 yr of age depends on:
a) ATTRITION – due to wear and tear from mastication, occlusal (upper) surface of teeth destroyed.
b) PERIODONTOSIS – regression of gums and periodontal tissues in advancing age , exposing neck , adjacent parts of roots, teeth become loose, fall off.
c) SECONDARY DENTIN –develop from within walls of pulp cavity ,
d) CEMENTUM APPOSITION- cementum increases in thickness due to change in tooth position , near end of root
e)ROOT RESORPTION- involves both cementum and dentin , show sharp grooves , starts first at apex and extends upwards.
f) TRANSPARENCY OF THE ROOT- not seen until 30 yrs of age , canals in dentin are wide at first , filled by mineral , transparency occurs from below upwards in lower jaw and from above in upper jaw.
BOYDE’S METHOD :
Cross striations in enamel of teeth, represent daily incremental lines, age calculated in terms of days from neonatal lines onwards, useful for dead infant’s age estimation.
Stack’s METHOD : From weight and height of infants.
MALE FEMALE Pelvis Deep funnel flat bowl Sub-pelvic arch Acute Obtuse Obturator foramen Triangular Oval Sciatic notch acute obtuse
