We present an unusual case of contact dermatitis of the face following the use of formocresol. A 23-year-old
man presented to our hospital, 3 days after his dental appointment, with moderate pain and a burning sensation related to a patch of darkly discolored skin. Questioning his dentist revealed that he used formocresol as an intracanal medicament. The root canals had been extirpated and formocresol had been placed into tooth #26 as a medicament. The dentist admitted that he accidentally touched the patient’s face with his formocresol-contaminated hands. Formocresol was removed from the canals and calcium hydroxide was placed. Then, a dermatology consultation was requested and it was diagnosed as irritant contact dermatitis. Complete healing was observed with appropriate drug therapy. The present case urges us to pay attention to preventive isolation methods and not to prefer formocresol, which can cause serious clinical manifestations, as an intracanal medicament.