Plaque detection. Dentist preparing to remove plaque (pink) from a patient's teeth using a high- speed brush. The plaque has been revealed by a disclosing tablet. The tablet contains a dye that binds to plaque when the tablet is chewed. After rinsing, the teeth are examined to identify areas of high plaque build- up. Plaque is a sticky substance comprising millions of bacteria, which collects around and between the teeth. It is a major cause of tooth decay and gum disease. The use of disclosing tablets can help improve brushing and flossing of teeth by highlighting missed areas.