<prompt> Burns involving skin superficial part of dermis is categorized asFirst degree burnsSuperficial 2nd degree burnDeep 2nd degree burnThird degree burns  <response>: First degree burns involve only epidermisSuperficial second degree involve upper layer of dermisDeep second degree involves reticular layers of dermisThird degree involves all layers of skinFourth degree burns involve not only skin but also subcutaneous fat and deeper structures 