Forensic Dentistry, Second Edition

88 Forensic dentistry

Individuality refers to the fact that fingerprints are unique; no two areas of

friction ridge skin are the same, not even on identical twins. The basis for this

statement rests in human embryology and genetics, beginning during fetal

development. The physiology of friction ridge skin begins with the develop-

ment of the volar pads, which are protuberances of tissue that begin to form

on the tips of the fingers at about the eighth week of gestation. The degree of

complexity of the volar pads (their size, shape, and location on the finger)

greatly influences ridge flow or level 1 detail.^12 These volar pads regress or are

C o m p a r i s o n

Po stmortem Antemortem

Identification

Level 1 Detail Level 1 Detail

Level 2 Detail Level 3 Detail Level 3 Detail

Level 2 Detail

Figure 6.4 the comparison phase of the aCe-v methodology involves the
examination of information or detail present in two prints. this information
consists of ridge flow (level 1 detail), ridge path (level 2 detail), and if visible, indi-
vidual ridge attributes (level 3 detail), such as ridge widths. if the information
present in the two prints is in agreement with no unexplainable dissimilarities,
an identification can be effected.