REPEATABILITY OF PREBRUSH AND POSTBRUSH DENTAL PLAQUE MEASURED VIA IMAGE ANALYSIS

Terry Auditorium

Objective. This research used image analysis to evaluate the reproducibility of natural plaque accumulation and removal measured instrumentally. Background. High levels of plaque contribute to gingivitis that affects more than half of the U.S. adult population. Methods. After institutional review and informed consent, healthy adults were enrolled in a study to assess the between-visit consistency of plaque measurement for overnight and post-brush plaque. At Day 1, subjects with overnight (unbrushed) plaque swished with a fluorescein rinse and expectorated, cheek retractors were inserted, and a single digital image was collected under standardized lighting conditions. After routine hygiene with a regular anticavity dentifrice (Crest® Cavity Protection) and standard manual toothbrush, disclosing and imaging were repeated. Approximately 1-week later, the imaging-brushing-imaging sequence was repeated. Each digital image was analyzed blind to visit sequence to determine area (%) plaque coverage, and paired images were compared to assess between-visit correlation. Results. A total of 51 subjects had prebrush and postbrush plaque measurements at both visits, and all data were included in the analysis. Mean (SD) age was 37.4 (15.4) ranging from 18-71 years. Plaque coverage varied across visits, ranging from 2.2-79.2% before brushing and 2.5-42.0% after brushing. Both the prebrush (r=0.84) and postbrush (r=0.80) plaque areas were well-correlated. Conclusion. Use of image analysis demonstrates a high level of between-subject variability in natural plaque accumulation and removal, that is highly reproducible between-visits. Grants. This study was fully funded by the Procter and Gamble Company. Grants. This study was fully funded by the Procter and Gamble Company.