A N U M B E R OF examination systems have been developed to record the oral hygiene status of an individual. Most systems use either selected teeth or the highest score for a group of teeth within a segment as the basis for their scores. When used for epidemiological studies or for evaluating the results of treatment in a study group these methods yield useful information. A numerical score, however, is of limited value for the clinician treating an individual patient. He is concerned with the locations where plaque accumulates and in the patient's progress in learning how to effectively clean these surfaces.