Use of Digital Plaque Image Analysis for Morning Brushing Effectiveness

Objectives: Digital plaque image analysis was used to instrumentally assess the effectiveness of morning brushing on overnight plaque accumulation. Methods: After IRB approval and informed consent, 37 generally healthy adults abstained from eating, drinking, tooth brushing or other oral hygiene overnight prior to morning (AM) evaluation. Subjects rinsed with 5 mL of a 1240 ppm fluorescein rinse and expectorated. Immediately thereafter, cheek retractors were inserted, and a single digital image was collected under standardized lighting conditions. Subjects were provided a regular anticavity dentifrice (Crest® Cavity Protection) and standard manual toothbrush for routine whole mouth oral hygiene, after which, rinsing and imaging were repeated. Image analysis was used to objectively measure fluorescein-disclosed prebrush (overnight) and postbrush plaque area on the anterior facial tooth surfaces. Prebrush and postbrush plaque areas were compared using a paired differences t-test. Results: The study population ranged from 19-62 years of age, with females comprising 76% of participants. Prior to brushing, overnight plaque ranged from 4.3-37.9% of tooth surfaces. Mean (SD) overnight plaque area was 15.9% (8.6). All subjects removed some plaque with brushing, with postbrushing area ranging from 2.2-22.0%. Mean (SD) postbrushing area was 7.9 (4.9), differing significantly (p<0.0001) from prebrush area. Most (57%) left more than 50% of plaque after brushing, and none removed all plaque. Conclusion: Morning brushing with a manual toothbrush and regular toothpaste is only partially effective, with digital plaque image analysis demonstrating approximately 50% of overnight anterior facial dental plaque remaining after brushing.