02 Mar Skin Anatomy: Dermis
In contrast to the epidermis, the dermis is comprised of mostly connective tissue.- The connective tissue includes collagen, elastin, extracellular matrix (ECM) and few cells.
- Fibroblasts are the principal cell of the dermis and they produce collagen, elastin and the ECM.
- The dermis also supplies nutrition and removes waste products.
- It contains numerous blood vessels and nerve endings.
- Ground substance, or extracellular membrane (ECM), form the lattice work that supports and frames collagen and elastin.
- ECM contains hyaluronic acid which are very hydrophilic (water-loving) and can bind up to 1,000 times their own weight in water.
- Hyaluronic acid is the ingredient found in many dermal fillers, used for lip augmentation.
- Of note, topically hyaluronic acid is too large of a molecule (3,000 nm) to penetrate the skin (50 nm). Beware of serums making these claims!
- Most skin tightening procedures target the dermis.