Scar muscular power and possibly heart failure. However, there are some tissues (e.g. bone) that can heal without any structural or functional deterioration. All scarring is composed of the same collagen as the tissue it has replaced, but the composition of the scar tissue, compared to the normal tissue, is different. Scar tissue also lacks elasticity unlike normal tissue which distributes fiber elasticity. Scars differ in the amounts of collagen overexpressed. Labels have been applied to the differences in overexpression. Two of the most common types are hypertrophic and keloid scarring, both of which experience excessive stiff collagen bundled growth overextending
Scar senses elevated mechanical stress loading, tissue will scar, and scars can be limited by stress shielding wounds. Small full thickness wounds under 2mm reepithilize fast and heal scar free. Deep second-degree burns heal with scarring and hair loss. Sweat glands do not form in scar tissue, which impairs the regulation of body temperature. Elastic fibers are generally not detected in scar tissue younger than 3 months old. In scars rete pegs are lost; through a lack of rete pegs scars tend to shear easier than normal tissue. The endometrium, the inner lining of the uterus, is the only adult tissue