
The 3M Patient Comfort System works by something called TENS, or transcutaneous electrical nerve stimulation. But don't let the name intimidate you. In fact, you can take comfort in the knowledge that TENS has been used by physicians for many years for both severe or recurring pain.
TENS is very effective for controlling pain during dental treatments. There are several theories on how it works. The popular "gate control theory" suggests that TENS signals create impulses that reach pain centers before the body's pain signals do, closing the "gate" to the transmission of pain - like a busy signal on a telephone.