What is Forensic Odontology, Determination by anatomic methods- pelvis, skull (general appearance , supraorbital ridges, orbit, glabella, zygomatic arches, mastoid process, manidble, palate, external occipital protuberance), long bones, sternum, scapula, Determination by cheiloscopy and palatoscopy, Determination by tooth morphology and dental index.

1. SEX DETERMINATION IN
FORENSIC
PRESENTED BY:
DR GAYATRI MEHROTRA

2. WHAT IS FORENSIC
ODONTOLOGY
Branch of dentistry which deals with the
proper handling, examination & evaluation of
dental evidences & with the proper
presentation of dental findings in the interest
of justice.

3. INTRODUCTION
Sex determination is an important step for
identification of human remains and for
dentolegal investigations in forensic odontology.
Teeth may prove to be an important factor for
identifying the individual through cellular,
immunological and enzymological examination of
their pulp.

4.  Determining the sex of
unknown human skeletal
remains is the second step in
the triad of building a dental
profile.
Therefore, sexing of teeth could be of
immense help in identification of human
remains investigation and solving crimes.

5. DIFFERENT TECHNIQUES
During last five decades many workers have
contributed for evolving different techniques of
sex determination from human skeleton.
These can be considered under following
headings:
 Determination of sex by anatomical method
which includes-
 Skull
 Pelvis , sacrum, long bones and other bones.

6.  Tooth morphology
 Determination of sex by cheiloscopy &
palatoscopy
 Determination of sex by nuclear testing
 From blood stains
 From hair
 From saliva
 From tooth pulp
 X chromosome
 Y chromosome

7. Some researchers believe that if the dental and
bone ages correspond closely, the skeleton is
probably male; if the bone age is advanced in
comparision with the dental age, it is probably
female.

8. DETERMINATION BY ANATOMICAL
METHODS
The determination of sex by examination of
the skeleton is based upon the appearances
of:
1) Pelvis(innominates + sacrum)
2) Skull (cranium + mandible)
3) Long bones(humerus , femur)
4) Sternum
5) Scapula, metacarpal bones

9. Krongman ranks accuracy
of sex determination
using the pelvis at 95%,
the skull at 90%, the
pelvis and skull at 98%
and long bones at 80%.

10. I) SKULL
The features that indicate sex are:
 General appearance
 Supraorbital ridges
 Orbits
 Glabella
 Zygomatic arches
 Mastoid processes
 External occipital protuberance
 Mandible
 Palate

11. WHEN COMPARED, THE FEMALE SKULL
APPEARS SMALLER AND MORE GRACILE.
THE MALE SKULL IS USUALLY LARGER
AND MORE RUGGED
MALE FEMALE
1. GENERAL
APPEARANCE

12. Supraorbital ridges: this is the region directly
above the orbit and nose , or the “brow ridge”.
Less pronounced = female
More pronounced = male

13. MALE
2. ORBITS
FEMALE
Squarish With
Roundish Margins
Roundish with
sharp margins

15. MALE FEMALE
Well Developed Ill Developed
3. GLABELLA

16. 4. ZYGOMATIC ARCHES
In females, the zygomatic arch is less
pronounced & tends not to extend posteriorly
beyond external auditory meatus.
In males, zygomatic arch is more pronounced &
tends to extend posteriorly beyond external
auditory meatus.

17. Zygomatic arch: wider in
males,narrower in females

18. 5. MASTOID PROCESS
Larger, more blunt in males and smaller, more
pointed in females.

19. 6. EXTERNAL OCCIPITAL PROTUBERANCE
Inion may be more prominent in males,
sometimes to point of appearing hook shaped.

20. FEMALE SKULL

21. MALE SKULL

22. 7. MANDIBLE

23. 8. CHIN( ANTERIOR MANDIBLE)
MALE FEMALE
Square shape
chin
Pointed chin

24. 9. RAMUS OF MANDIBLE
Mandible in male is closer to right angle than
female.
In females, the ramus is at an obtuse angle.
Ramus in males is wider & larger.

25. 10. PALATE
MALE FEMALE
Larger, wider
and broader
Smaller and
narrower

27. II) PELVIS

28.  5 features in innominate that indicate sex in
pubic region are:
 Width of sciatic notch
 Subpubic angle
 Ventral arc
 Ischio-pubic ramus
 Acetabulum diameter

29. 1) SCIATIC NOTCH

30. 2) SUB-PUBIC ANGLE
Sub-pubic angle is much wider in females
than in males

31. 3) VENTRAL ARC

33. III) SACRUM
In female, sacrum is shorter and wider than in
male and bone is also directed more obliquely
backward.

34. IV) STERNUM
Variable usefullness in sex estimation.
In males, body of sternum is >2X length of
manubrium & in females <2X
 <125 mm=females these figures are
 >155 mm=males from Bass

35. DETERMINATION BY CHEILOSCOPY &
PALATOSCOPY

36. IV
III II
I’
I

37. Graph 3: Statistically significant difference was observed
between two genders (P < 0.001). Type III pattern was
more common among males,whereas types I′ and I were
more common among females

39. The palatal rugae, like fingerprints, do not
change during the life of the individual.
 They are protected from trauma and high
temperatures because of their internal position
in the oral cavity.
Palatoscopy can be of special interest in those
cases where there are no fingerprints available
like decomposed bodies, burned bodies and
conditions were both the upper limbs are
missing.

40. Based on the direction rugae were classified as:
1) Forwardly directed rugae – associated with
positive angles
2) Backwardly directed rugae -associated with
negative angles
3) Perpendicular rugae – associated with zero
angles.

41. BA
C

42. A B

43. TYPE OF RUGAE INCIDENCE
CURVED RUGAE FEMALES>MALES
STRAIGHT RUGAE FEMALES>MALES
WAVY RUGAE MALES>FEMALES
FORWARDLY DIRECTED
RUGAE
FEMALES>MALES
BACKWARDLY DIRECTED
RUGAE
MALES>FEMALES
PERPENDICULAR RUGAE MALES>FEMALES

44. DETERMINATION BY TOOTH
MORPHOLOGY AND DENTAL INDEX
Mandibular cuspid show the maximum
sexual dimorphism:
 Mesiodistal diameter<6.7 mm(female)
 Mesiodistal diameter>7mm (male)
Root length of maxillary cuspids is >3mm
in males

45. DENTAL INDEX
Incisor index(Ii)- proposed by Aitcheson

( LI <CI in females)

46. Mandibular Canine index(MCI) by Rao and
associates:
Mandibular
canines can be
considered as
the ‘key teeth’
for personal
identification

47. The cut-off value or standard MCI value
obtained by Rao and associates was 0.274 .
If the MCI value of a skull specimen is less
than or equal to the standard MCI , the
individual is categorized as female.
A value more than the standard MCI would
group the person as male.

48. DETERMINATION BY NUCLEAR
TESTING

49. WHY TEETH??
Since teeth can resist extreme condition,
they are the excellent source of DNA.
This facilitates comparision with the known
biological ante-mortem sample of the person
such as hair, epithelial cells from the tooth
brush or a biopsy specimen.

50. The mass of chromatin in nuclei was
frequently present in females but only rarely
in males.
Distal portion of the human chromosome
fluoresces brightly when stained with
quinacrine mustard.
Vaginal epithelium and buccal epithelium
may be used for nuclear sexing.

51. 1) FROM BLOOD STAIN
‘drumstick’ in neutrophil leucocytes is a female
characteristic.
Fluorescent Y-chromosome in hairs and blood
stains.
Radioimmunoassay (RIA) for sex determination
in dried blood stains.

52. 2) FROM HAIR
Sex chromatin in external root sheath of
plucked hair, aids in determining sex of the
individual.

53. 3) FROM SALIVA
The determination of sex by saliva spots and
the application of cigarette ends using sex
chromatin technique, and the fluorescent Y-
chromosome technique for determining sex
from saliva may be used.

54. 4) FROM DENTAL PULP
A method of identifying the sex from a single
human tooth on the basis of fluorescence of
the distal end of a long arm of Y-chromosome
in the nucleated cell of dental pulp.
But this method becomes increasingly
unreliable as putrefaction proceeds .
Using acetin-orcin stain for Y-chromosome a
method to detect both sexes using very small
amount of pulp.

55. Necrosed pulp can also be studied by a
method by which one can detect Y-
chromosome (F-bodies) using 0.5% quinacrine
HCL staining and Toludiene blue staining for
detecting female X- chromatin (Barr body).

56. CONCLUSION
Forensic odontology in India is an emerging
field and relies a lot on inexpensive and easy
means of identification of persons from
fragmented jaws and dental remains.
Teeth are considered a useful supplement and
adjunct to sex determination and not
recommended as the sole indicator of sex.

57. REFERENCES
 Textbook Of Dental And Maxillofacial Radiology- by
Freny R Karjodkar ( 2nd edition).
 Shafers textbook of oral pathology- by R Rajendran and
B Sivapathasundharam( 6th edition).
 Study of palatal rugae pattern among the student
population in Mangalore ( J Indian Acad Forensic Med.
April-June 2011, Vol. 33, No. 2 )
 Latent lip print development and its role in suspect
identification (Journal of Forensic Dental Sciences /
January-June 2013 / Vol 5 / Issue 1 )

58. QUESTIONS
Importance of sex determination in forensic?
What is cheiloscopy?
Various source of DNA for sex determination?

59. Various method for sex determination?
Role of palatoscopy in sex determination?

60. THANK YOU