In dermatology, an abrasion is a damage to the skin that affects only the surface, generally not deeper than the epidermis. But it can give mild bleeding. Mild abrasions, also known as 'grazes' do not scar, but deep abrasions may lead to the development of scarring tissue.
Abrasion injuries occur rather often when exposed skin comes into moving contact with a rough surface causing trauma to the upper layers of the epidermis.
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