Explorers are designed to adapt to a specific area or tooth surface. EXD 11-12 Explorers has a gentle bend for premolars and molars. It is used for the removal of sub-gingival calculus and root planing. Explorers are the most popular and common, less traumatic than the Universal type. They are site-specific as they are designed and assorted to adapt to the specific area or tooth surface to be treated.