uniqueness and permanence of friction ridge

The Basic Premises Of Friction Ridge Identification

The Uniqueness and Permanence of Friction Ridge Skin

Jury G. Rocamora, MSCrim.http://frictionridge.weebly.com

Friction ridge skin has been studied in relation to:

inheritance and population differences (eugenics, the selection of best breeding stock to develop superior strains of humans) by Francis Galton (1892)

clinical medicine by Harold Cummins (1936).

value of friction ridge prints in the field of criminal identification by Henry Faulds (1880)http://frictionridge.weebly.com

Rationaleif the expert does not have a basis for understanding the permanence and uniqueness of a feature . . . then the expert cannot give any consideration to that feature in making an identification.- Pat Wertheim, 2000.

http://frictionridge.weebly.com

RationaleNo expert should ever give weight to any feature he or she does not understand or is not able to defend in court.- Pat Wertheim, 2000.


RationaleBy the late 1930s, fingerprint examiners were already routinely identifying latent prints without knowing anything about the morphology of their formation Simon Cole,1999.


Skin The largest organ of the human body. http://frictionridge.weebly.com

It is approximately 15 to 20% of our body weight and occupying almost 2 sq. m. (18 sq. ft.) of surface area.

The skin that covers most our body is relatively smooth, except palmar side of the hands, and in the plantar side of the feet.

Such skin is called as volar skin or friction ridge skin.It is only 0.8 sq.m. and its the thickest

Friction Skin






The Basic PremisesPrinciple of Permanence- subsurface structure of friction skin

Principle of Uniqueness- prenatal development of friction ridgeshttp://frictionridge.weebly.com

The Principle of Permanence the adherence of the epidermal cells to each other the basal cell layer of the epidermis, and its attachment to the basement membrane, and the attachment of the basement membrane to the dermis.http://frictionridge.weebly.com

Two (2) layers of skin Epidermis

Dermis



Sub-layers in Epidermis


DermisEpidermisDermal PapillaePrimary RidgeSecondary RidgePoreshttp://frictionridge.weebly.com



Sub-divisions of EpidermisStratum Corneum , or Horny Layer

Stratum Lucidum, or Hyalin Layer

Stratum Granulosum, or Granular Layer

Stratum Spinosum, or Spinous Layer

Stratum Basale, or Generating Layer

Produces cells to replaced those being shed in the exposed superficial layer. The deepest layer; parallel to the basement membrane.Called the pickle cells because of the many-sided cells that have spines protruding from their surface. Initiates the process of keratinization associated with the dying process of cells. The last of the living cells.Consists of flat and translucent dead cells that contain protein called eleidin. Appears only on palms and soles.The outermost layer. Flat, arranged in rows as dead cells. Desmosomes undergo degradation.


Cell progression

These cells move on toward the surface, Filled with keratin, become flatter and dryer. The cells in the mid-layers are called cuboidal cells. And when they get to the surface, they start to be cornified, that means that they release keratin, become dry and are flat. Then they die and shed off from the surface. The entire progression of keratinocytes in the basal layer until it reached to the horny layer, the cells (keratinocytes) are always bound by desmosomes. After keratinizations occur, cells will slough off like scales in the atmosphere.This process is called desquamation. http://frictionridge.weebly.com

Keratinocytes become cornified as they progressed towards the surface


Progression of skin cells


Cells are bound by desmosomes


The Basement MembraneBasement membrane separates the epidermis and dermis

It serves as a filter of all the nutrients, oxygen, waste and chemical signals to and fro the epidermis.

The basal layer cells is strongly attached to the BMZ through a hemidosmosome and small fibers.http://frictionridge.weebly.com

Basement Membrane

The DermisClosely attached to the BMZ through extensive network of fibers. Divide into papillary and reticular layers.Papillary layer surface area is increased by the dermal papillae.Dermal papillae strengthen the epidemis-dermis junction.http://frictionridge.weebly.com

The Principle of UniquenessBefore primary ridges emerge

- units of multiplying cells randomly growing- units fuse together and form as linear ridges, creating visible ridge structure at the bottom of epidermishttp://frictionridge.weebly.com

The onset of the first visible ridge structure at the epidermal-dermal junction
































The Principle of UniquenessDevelopment of a ridge- 10.5 weeks EGA, ledge-like formations form on the bottom of epidermis- 14 weeks, primary ridges increase its dimension and penetrate dermis- 15 weeks, sweat glands begin to appear- 16 weeks, secondary ridge emerge between primary ridges. Sweat glands penetrate downward, primary ridges push cells upward- 17 to 24 weeks, minutiae permanently set. Secondary ridges are almost the size and depth of primary ridges.http://frictionridge.weebly.com

Critical stage of friction skin formationBEFORE the critical stage of friction skin formation


Critical stage of friction skin formationDURING: 10-11 weeks EGA; Primary ridge protruding into the dermis


Critical stage of friction skin formation


Critical stage of friction skin formation


Critical stage of friction skin formationNew primary ridges are thought to form


Critical stage of friction skin formationAFTER: Secondary ridges continue to mature, surface ridges continue to form


Critical stage of friction skin formationAFTER: Secondary ridges continue to mature, surface ridges continue to form


Critical stage of friction skin formationAFTER: 17 to 24 weeks, minutiae permanently set. Secondary ridges are almost the size and depth of primary ridges.


The Principle of UniquenessThree (3) levels of Uniqueness of mature friction skin

- Level 1 is the overall pattern configuration, the general ridge flow tendencies and the general morphology (size and presence of incipient ridges) exhibited by the friction ridge impression.


Uniqueness of Level One DetailsGrowth and regression of the volar pads affect the alignment of ridges

Genetics is not alone in controlling the shape of the volar pads, also tensions from the environment of the fetus, bone morphology, and others, ex. Identical twins, clones.



DEVELOPMENT OF THE HAND AND VOLAR PADS









Volar pads

STAGES OF VOLAR PAD FORMATIONStages of volar pad formation








STAGES OF VOLAR PAD FORMATIONVolar pad is high and symmetrical




STAGES OF VOLAR PAD FORMATION










STAGES OF VOLAR PAD FORMATIONComplete regression


Converging ridge fieldsThree (3) areas that primary ridges begin to form: apex of the volar pad, tip of the finger, and interphalangeal flexion crease area












DELTA FORMATIONThe meeting of three (3) ridge fields












Large count pattern formationLarge count pattern formation: ridges form in the center first and proceed outward














Small count pattern formationSmall count pattern formation: ridges form on the outer perimeter of the pattern area and proceed inward












SYMMETRICAL VOLAR PADSLARGE RIDGE COUNT WHORL PATTERN: Ridge proliferation was early; volar pad is high


SYMMETRICAL VOLAR PADSLESSER RIDGE COUNT WHORL PATTERN: Volar pad regressing






SYMMETRICAL VOLAR PADSARCH PATTERN: Volar pad totally regressed during the onset of primary ridge


ASSYMMETRICAL VOLAR PADSLARGE RIDGE COUNT LOOP PATTERN: Ridge proliferation was early; volar pad is high


ASSYMMETRICAL VOLAR PADSLESSER RIDGE COUNT LOOP PATTERN: Volar pad regressing






ASSYMMETRICAL VOLAR PADSARCH PATTERN: Volar pad totally regressed during the onset of primary ridge



- Level 2 refers to the type and position of minutiae, points, or ridge characteristics, including their morphology (size and shape) which are a unique formation.


Uniqueness of Level Two Details As the volar surface is growing, existing ridges are separated new ridges emergeDuring the critical stage, volar surface is continually ridgedBifurcation results of new ridges pulling away from existing ridges to fill the unridged surfaceShort ridge results of developing ridge sandwiched between established ridgesGoverned by interdependent stresses, tensions, interactions with surrounding ridges


Mechanical fusion theoryMechanical Fusion Theory: As existing ridges separate, a demand for new ridges is created because the surface has a tendency to be continually ridged


















Mechanical fusion theory16 weeks EGA, secondary ridges form, minutia becomes set


Mechanical fusion theoryRidges increase in size and become mature













- Level 3 includes all dimensional attributes of a ridge, such as ridge path deviation, width, shape, pores, edge contour, incipient ridges, breaks, creases, scars and other permanent details.


Uniqueness of Level 3 DetailsRidge units have been subject to genetic and physical pressures while growingRidge units are growing at random and independently (differential growth)As it mature, it fuses with each other to form a complete friction ridge Unique ridge unit + Unique ridge unit Unique friction ridge


Uniqueness of Level 3 DetailsAlong the surface of the ridge are minute openings called as PoresPores function as toRegulate body heatRemove waste from the bodyIncrease friction by depositing moisture onto the surface of the ridgesPores contribute to individuality


Unusual Fingerprint PatternsDouble LoopAccidental WhorlCaused by irregular volar pad growth or regressionGrowth of bone in distal phalanxPressure on digit while growingDysplasia of Downs syndrome patient

Dissociated ridges/ Dysplasia



A ReviewCellular attachments ensure permanence

Variable stresses and cellular distributions account for individuality on all three levels of detail

The Endhttp://frictionridge.weebly.com

ReferencesKasey Wertheim and Alice Maceo, The Critical Stage of Friction Ridge and Pattern Formation, Journal of Forensic Identification, 52 (1), 2002

No less than the Holy Quran is reminding us of Allahs (the Creator of mankind) power to provide us unique identifier of our self. Surah 75:4 says,

Yes, We are Able to put together in perfect order the tips of his fingers.http://frictionridge.weebly.com

uniqueness and permanence of friction ridge

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