Topical guanethidine relieves dentinal hypersensitivity and pain.

The topical application of guanethidine solution to the affected teeth has been successful in relieving natural and clinically induced dentinal pain and hypersensitivity in 13 of 14 dental patients in a pilot study. The mechanism of this analgesia was unclear but probably involved anti-noradrenergic block as there was no evidence of local anaesthesia. Further studies may generate new ideas about the cause of the excruciating pain and hypersensitivity often associated with the acute exposure of tooth dentine and lead to new ways of managing the discomforts of dental conservation and restoration.