Dermis

Function

The dermis is skin's living core — a collagen-and-elastin feltwork that gives skin its tear-resistance and bounce. Type I collagen ropework here is the target of ageing's UV-driven degradation (wrinkles), and its fibroblasts wage the wound-healing campaign: inflammation, proliferation, remodelling over months.

It warehouses the appendages — hair follicles with their arrector pili, sebaceous glands, coiled eccrine sweat glands — plus the sensory corpuscles (Meissner for flutter, Ruffini for stretch, Pacinian in deeper layers for vibration) and the vascular plexus that flushes and blanches with emotion and temperature.

Blood supply

Superficial and deep dermal plexuses.

Nerve supply

Myriad specialised receptors; sympathetic fibres to glands and vessels.

Clinical relevance

Scarring

Deep dermal injury heals by collagen replacement — hypertrophic or keloid scars overproduce it.

Scleroderma

Autoimmune fibroblast activation stiffens the dermis — skin that cannot pinch, fingers that turn white and blue in cold.