Forensic Medicine

1. FORENSIC
ODONTOLOGY

2. Forensic odontology
• Forensic odontology is a branch of forensic
medicine, and in the interest of justice deals
with the proper examination, handling and
presentation of dental evidence in the court
of law.

3. Features which can be established by
dental examination;
1. Age
2. Sex
3. Race
4. Blood group ( from saliva)
5. Economic Status ( sometimes)
6. Occupation
7. Use of specific medicines
8. General facial characteristics

4. Stage of tooth development has
two periods.
1. Pre-natal period
2. Post-natal period.

5. Pre-natal period
• Calcification of tooth starts in incisors at
the tips of milky teeth at 5th month of
intrauterine phase.
• At time of birth calcification occur;
Incisors = 2/3
Canines = 1/3
molars = tip.

6. 1. Age
1. Eruption of temporary and permanent
teeth.
2. Gustafson’s criteria.

7. Two sets of teeth
1. Temporary, deciduous or milk teeth.
2. Permanent teeth.

8. Temporary teeth
• These are 20 in numbers including
( in each jaw) :
Incisors = 4
Canines = 2
molars = 4

9. Permanent teeth
• 32 in number, including (16 in each jaw):
Incisors = 4
Canines = 2
Premolars = 4
Molar = 6

10. Temporary teeth Permanent teeth
1. Small, narrow & light Big, broad & heavy
2. China white in color Ivory white in color
3. Neck is more
constricted
Neck is less constricted
4. Edges serrated Edges not serrated
5. Anterior teeth vertical Anterior teeth inclined
somewhat forward
6. Molars are usually
larger
Premolars which replace
the temporary molars are
smaller.

11. Age of eruption of temporary teeth
TOOTH AGE
Lower central incisor 6-8 month
Upper central incisor 7-9 month
Upper lateral incisor 9 month
Lower lateral incisor 10 month
First molars 12th month
Canines 18 month
Second molars 2 years

12. Temporary teeth
• Temporary dentition start at = 6 month
• completed = 2.5 years
• in 1 year total teeth = 8-12
• 1.5 year total teeth = 16
• Calcification of roots completed by the end
of third year.

13. Permanent teeth eruption
TEETH Years of eruption
First molars 6
Central incisors 7
Lateral incisors 8
First premolar 9
Second premolar 10
Canines 11
second molars 11-12
Third molars 17-18 ( variable)

14. Permanent teeth
• If the 4 wisdom teeth are present, then the
age is > 17 years
• MIX dentition period is = 6 – 12 years.
• Calcification of roots is completed within 3-4
years of eruption.

15. Gustafson`s method
• This method is used for age estimation in
adults by studying the progressive
changes in an individual tooth.

16. Gustafson`s criteria
1. Degree of Attrition (wearing off teeth )
2. Periodontosis ( loosing of teeth )
3. Secondary dentine formation
4. Cementum deposition.
5. Root resorption
6. Root trasperency.

17. • MILES ( 1963) suggested that transparency
of root is most reliable criteria.
• BOYD ( 1963 ) devised a age estimation from
incremental lines of enamel.
• These lines can be seen on histological
section of teeth and represent daily
increments of growth.
• A well marked line known as NEONATAL
LINE, is formed at birth.

18. DIFFERENCES IN MALE AND
FEMALE DENTITION
FINDINGS MALE FEMALE
Size of upper
central & lateral
incisors
Different Same
Size & shape of
teeth
Mandibular teeth
are less pointed
& bigger
mandibular teeth
are more pointed
and smaller
Mandibular 1st
molar
Has a fifth cusp Fifth cusp is
absent

19. Race of person
• Characterestics of Mongoloids teeth:
1. Shovel shaped upper incisors.
2. Enamel pearls: are small nodules of enamel
on the surface.
3.Taurodontism ( bull tooth): the pulp cavity of
molars is wide and deep and the roots are
fused and bent.
4. Congenital lack of third upper molars is
common.

20. • Carbelli’s cusp: Small nodules on
lingual surfaces of maxillary molar is
common in WHITE RACES.
• Large teeth with more cusps in molars are
common in NEGROID.

21. Common identifying features of
teeth
• 1. Faulty development; Teeth may be
undersized (small), oversized, notched, or
present some other irregularities as a result of
faulty development and malformation.
• 2. Faulty alignment; the defect in the
alignment may be 1. In the space b/w the teeth
eg. Widely spaced teeth, overriding teeth. 2.
b/w the teeth of upper and lower jaw.

22. Stains;
• * Pan (betel leaf, tobacco) chewing habit stains the
teeth with dark brown or black deposit.
• * Yellowish or dark brown stains on the back of incisor
teeth are common in cigarette smokers.
• * Chalky white or yellowish brown areas of
discoloration on enamel, are found in FLOROSIS.
• * COPPER causes green, and MERCURY and LEAD
causes blue-black line on the gums.
• * PHENYTOIN induces hyperplasia of gums. May
indicates and suggests epileptic seizures as a cause
of death.

23. • Localised attrition:
Pipe smokers may have localized wear off
teeth, either on incisors or at the angles of
the mouth due to position of pipe.
Notched incisors from holding thread and
pins b/w teeth suggest that person was
tailor or hair-dresser or a cobbler.

24. • Medico-legal aspects of dental study
• Identification of the individual
• Cause of death. The teeth resists putrefaction and the
amount of deposition of heavy metals can be detected
for a considerable period after death that is especially
helpful in poisoning cases
• In chronic phosphorus poisoning; evidence of phossy
jaw is characteristic.
• Bite marks suggest sexual assault.
• Artificial dentures; when dislodged can sometimes
cause choking in the elderly.
• Pink teeth; in putrefied bodies near gum line, teeth are
of pink color, it is due to dentine being stained by
heamoglobin products.

25. • Charting of teeth:
• Any extractions, recent or old from the
condition of the socket.
• Any fillings, number and position.
• Artificial teeth, whether of gold. Porcelain or
stainless stain.
• Prosthetic work.

26. • Any crowned teeth.
• Any broken teeth
• Pathological conditions in teeth, jaws and
gums.
• Congenital defects, such as enamel pearls,
carbelli`s cusps or ectopic teeth.
• Malpositioned teeth, rotated or tilted
• General state of care and hygiene like
caries. Plaque. Tobacco staining, gingivitis
ets.