Only dermis is vascularized. Nutrients reach epidermis by diffusing through the tissue from the blood vessels. Underneath dermis is hypodermis (superficial fascia), also called subcutaneous tissue which is composed of loose connective tissue (mostly areolar and adipose).
A collagen dressing is a type of wound dressing that is made with a form of collagen to aid in the body's healing processes. Collagen is a category of structural proteins that are naturally present in almost every part of the human body and are especially common in connective tissue.
A dressing also absorbs any drainage that may come from the incision or wound. Sometimes dressings are used after a medication is applied to the incision or wound; the dressing keeps the medication in contact with the incision or wound. dressing is a clean cover over an incision. A gauze dressing is secured to the skin with surgical tape. Some dressings are clear and adhere to the skin without tape.