The dermis is the middle layer of skin located between the epidermis and subcutaneous fat. It varies in thickness from 1mm on eyelids to 5mm on the back and makes up 15-20% of body weight. The dermis provides nutrients to the epidermis and dermal appendages, cushions the body against injury, retains water, aids thermal regulation, and contains receptors for sensory stimuli. It has two layers - a thin papillary dermis that interdigitates with the epidermis, and a thick reticular dermis that merges with subcutaneous fat and contains large collagen and elastic fibers. The dermis develops from mesenchymal cells and contains components like elastin, collagen, ground

1. DERMIS
DR SUBODH KUMAR SHAH

2. INTRODUCTION
Bounded externally by junction with epidermis and
internally by subcutaneous fat
bulk of the skin
Varies in thicknes
5 mm on back
1 mm on eye lids
15 to 20% of weight of human body

3. FUNCTIONS OF DERMIS
 Provides nutrients to epidermis and dermal appendages.
 Cushions the body against mechanical injury.
 Retains water.
 Aids in thermal regulation.
 Contains receptors of sensory stimuli.
 Collaborates during development of dermoepidermal junction
and appendages.
 Interacts in repairing and remodeling the skin.

5. PAPILLARY DERMIS
Thin and superficial
1/10th of dermis that interdigitates with the ridges on
undersurface of epidermis
Small bundles of collagen fibres & oxytalan elastic fibres
Mature elastic fibre not found
High density of fibroblasts
Region contains end of anchoring fibrils &anchoring
plaques

7. RETICULAR DERMIS
 9/10th of dermis
 Merges with subcutaneous fat
 Composed of large diameter collagen fibres
 Mature elastic fibres present
 These two fibres system interact & gives dermis strong resilient properties
 In regions such as nipple, scrotum there are smooth muscle fibers in reticular
dermis

8. DEVELOPMENT
Most of the dermis from mesenchymal cells that originate from
mesoderm

9. COMPONENTS OF DERMIS
Elastin.
Collagen.
Ground substance.
Microfibrils.
Glycoproteins.
Cellular components.
Vascular elements.
Neural elements.

10. BLOOD SUPPLY TO DERMIS
Derived from musculoskeletal arteries that penetrates the subcutaneous
fat.
Dermal vasculature is divided into:
 Superficial vascular plexus
 Deep vascular plexus

12. NERVE SUPPLY
Skin is innervated by:
 Somatic sensory
 Sympathetic autonomic
Pattern of nerve fiber distribution is similar to
vascular patterns

13. THANK YOU 