As each fine needle punctures the skin, it creates a channel or micro-wound. The microchannels created spontaneously close after 10 minutes so that epidermal barrier integrity remains intact.

The needles injure superficial dermal collagen strands and small blood vessels triggering a controlled cascade of inflammation including the release of platelet-derived growth factors transforming growth factor-alpha and beta (TGF β-3), connective tissue activating protein, connective tissue growth factor, and fibroblast growth factor. These lead to the production of new collagen, elastin, and capillaries.

Neovascularisation and neocollagenesis lead to thickened skin and a reduction of scars, with improved skin texture, firmness, and hydration.