If you look at the research on the biological mechanisms of action, acupuncture needles and dry needles are doing the same thing: providing a novel stimulus to the CNS which has effects on many neuroanatomical regions associated with pain. Needle insertion stimulates nerve endings which can block nociceptive signaling according to gate-control theory, needle insertion also stimulates endogenous opioid release, purinergic signaling and modulation of the endocannibinoid system.

Another interesting concept is acupuncture helps to stimulate improved micro-circulation, while encouraging the removal of cellular exudates and drainage of metabolic waste.