Reticular layer of dermis

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General histology of the skin.

The skin consists of three primary layers: the epidermis, dermis, and hypodermis (subcutaneous tissue). Within the dermis, two specific layers can be identified: papillary and reticular layers.

The reticular layer forms the deeper, thicker layer of the dermis and extends from the overlying papillary layer on the surface to the subcutaneous tissue/hypodermis beneath. It is composed of dense irregular connective tissue containing mainly type I collagen fiber bundles that form a meshwork, but also some elastic fibers that contribute to the elasticity of the skin.

The meshwork of collagen fibers surrounds hair follicles, sebaceous glands and sweat glands, as well as nerve fibers and a deep plexus of blood vessels which extend into the subcutaneous layer.

The thickness of the reticular dermis differs significantly across various parts of the body, being thickest on the back and thinnest on the eyelids.

The reticular layer of dermis provides strength, elasticity, and structural support to the skin. Additionally, it performs several important functions including: housing hair follicles and glands, supplying nutrients to superficial layers of the skin and facilitating sensory perception, immune defense and thermoregulation.