ABSTRACT
Granulation tissues, hypertrophic scars, hypertrophic scars treated with mechanical pressure and mature scars from deep thermal injuries, or equivalent trauma, were examined for the presence and dermal distribution of mast cells. Statistical analyses of mast cell counts indicate that 1) the hypertrophic scar contains significantly greater numbers of mast cells than the other tissues studied. 2) as granulation tissue develops interstitial collagen, mast cells begin to appear, 3) mature scars contain significantly fewer mast cells than hypertrophic scars, 4) based on mast cell data, the effect of pressure therapy is first detected in the upper and middle reticularis of the dermis, and 5) on a mast cell statistical basis mature scar and hypertrophic scar under pressure are indistinguishable.