|Posted on Thursday, September 15, 2005 - 10:56 am: ||
Washing hands does not "wash away" fingerprints.
Fingerprints are formed during the 3rd to 4th month of fetal development and do not change throughout the life of the individual except when damage to the basal layer occurs (scarring, diseases such as leprosy, etc.). Here is an excellent online explanation of friction skin growth at Mary Beeton's Ridges and Furrows site.
During approximately each 30 days, the entire series of skin layers forming the epidermis is replaced with new layers of skin cells. If a person were to physically or chemically damage (such as sanding-off) the outermost layers or skin (these layers of skin are already "dead" skin cells), it could be expected that within 30 days the fingerprint ridges would be completely replaced as if they had never been damaged. If, however, the damage occurs as deep scarring or disease impacting the deep (living) skin cell layers of the dermis, then the fingerprint would be permanently scarred and all future cycles of 30-day skin replacement would reflect the new scar formation. Permanent scarring generally is represented with "puckered" ridge formations whereas temporary paper cuts, etc., do not normally have such ridge "puckering."
|Posted on Wednesday, September 14, 2005 - 07:10 pm: ||
My assignment for my anat and phys class is to write a paragraph about fingerprints. My instructure told us that doctors and nurses sometimes don't have fingerprints because they wash their hands so frequently. How long would it take for them to get their fingerprints back?