Plaque will be scored based on the Turesky modification of the Quigley—Hein Plaque Index (PI) (Turesky 1970). A score of 0 - 5 will be assigned to six sites of each tooth (distobuccal, buccal, mesiobuccal, distolingual, lingual, mesiolingual) following the use of a disclosing solution. The following criteria will be used: