2. INTRODUCTION
• Dermatoglyphics is the study of epidermal ridge patterns and lines (fingerprints)
on the skin of the fingers, palms, toes, and soles.
• Dermatoglyphics is a Greek word, “derma” means skin and “glyph” means
carving.
• A dermatoglyph is literally a ‘skin carving’ or furrow in the skin.
• Ridges appear on the hands between sixth and seventh week of fetal development
and are fully formed by the 21st week and remain largely unchanged after this
period.
• Epidermal ridges are formed in the same intrauterine period when neuronal
development takes place in the intrauterine life of a fetus.
• Thus, dermatoglyphics is correlated with genetic abnormalities and is useful in
the diagnosis of congenital malformations and many other medical disorders.
3. Dermatoglyphics classification
• Digital fingerprint patterns were classified into eight types
• Ulnar loop (UL), radial loop (RL),plain arch (PA), tented arch (TA), plain whorl (PW),
central pocket loop whorl (CPL), double loop whorl (DL), and accidental whorl (A).
• Pattern classification described by the Federal Bureau of Investigation (FBI), USA
NOTE: Each and every individual has unique fingerprints, even in twins. These fingerprints remain the same
lifelong from their development unless they are damaged by dermal injuries.
4. WHORL – Whorl is distinguished by concentric circles.
• Form circular or spiral patterns, like tiny whirlpools.
• There are mainly two groups of whorls
Plain whorl - concentric circles, with one complete circle and two deltas.
Central pocket whorl - this is a loop with a whorl at the end of it, which can be oval, spiral, or
circular.
• True whorls typically possess two triradii or delta.
• Whorls make up about 35 percent of pattern types.
Whorl with 2 triradii
5. Triradii or Delta
• A place where two lines run side-by-side and then diverge to form a triangle.
or
• A place where all the ridges meet.
6. A plain whorl consists of one or more ridges which makes complete circuit
with two deltas. When an imaginary line is drawn, at least one recurving
ridge within in the inner pattern area is cut or touched
A central pocket whorl – when an imaginary line is drawn, no recurving
ridge within the inner pattern area is cut or touched.
PLAIN WHORL
CENTRAL POCKET WHORL
7.
8. LOOP
• Loops are the most common type of fingerprint, accounting for around 60% to 70% of all prints. They are
characterized by a circular or oval-shaped pattern.
• A loop is formed when one or more ridges entering from the same side recurving, existing form the same side
• Loop must have one delta.
Radial loop - The loop where the ridges start from radial bone. The loop which open towards your
thumb. Radial loops are not very common.
Ulnar loop – The loop where the ridges start from ulnar bone. The loop which opens towards your little
finger.
9. ARCHES
• Arches are the least common type of fingerprints, making up around 10% of all. They are characterized
by a wave-like pattern. They occur in two different styles.
• RIDGES enter from one side to another.
Plain arch (A):This is the simple of all fingerprint patterns. The ridges run from left side to other side
with a small rise at the center like a hill or hump.
Tented arch(T): In this ridges entering from left side making an upright thrust at the center flowing
towards the right side of the pattern.
• No delta or triradii.
10. RIDGE COUNTING
The ridge count is the number of ridges intersected by a line between
the triradial points to the point of core.
11. Finger Impression Pattern No. of
triradii
Ridge
count
Thumb
Index
Middle
Ring
Little
Finger Impression Pattern No. of
triradii
Ridge
count
Thumb
Index
Middle
Ring
Little
LEFT RIGHT
TOTAL FINGER RIDGE COUNT – represents some of the ridge count of all ten fingers
Total =
Total =
12. Flexion creases
• The lines on our palms are scientifically known as palmar flexion creases. These creases begin to
form around the 12th week of gestation.
13. Atd angle measurement
• The "ATD" angle is a dermatoglyphic trait formed by drawing lines between the triradii below
the first and last digits and the most proximal triradius on the hypothenar region of the palm.
• It is how fast brain work….response.
• ATD angle indicate the Speed of our brain and muscle coordination in conveying and
Transmitting information.
• Lesser the ATD angle , faster the brain response.
• The ATD angle is a dermatoglyphics trait formed by drawing lines connecting the a -triradiu
(under index finger), the t- axial triradius (near the wrist) and the d- triradius (near the little
finger) points on the palm.
• The angle indicates the speed of our brain and muscle co- ordination in conveying and
transmitting information.
• It reflects how fast our brain responds to the information delivered to our brain through sight,
touch, smell, taste and hearing.
• Lesser the degree of our ATD angle, the more is our learning sensitivity.
16. Simian crease
• STPC- single transverse simian crease.
• Single palmar crease appears in about 1 out of 30 people.
• Males are twice as likely as females to have this condition.
• Some single palmar creases may indicate problems with
development and be linked with certain disorders.
• Down syndrome
• Aarskog syndrome
• Fetal alcohol syndrome
• Trisomy 13
• Rubella syndrome
• Turner syndrome
• Klinefelter syndrome
• Pseudohypoparathyroidism
• Cri du chat syndrome
