Method: After institutional review and informed consent, healthy adults were enrolled in a study to assess plaque accumulation overnight and immediately after prophylaxis. 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. Separately, air-dried calculus was assessed on 18 sites on 6 mandibular lingual surfaces (as presence or absence). Subjects received a routine whole mouth dental prophylaxis, immediately after which, fluorescein rinsing and imaging were repeated. Each digital image was analyzed blind to visit sequence to determine area (%) plaque coverage on the anterior facial tooth surfaces, and paired images were compared to assess between-visit differences.
Result: A total of 28 subjects had overnight and post-prophylaxis measurements, and all data were included in the analysis. Mean (SD) age was 38.2 (15.4) ranging from 23-73 years, 61% were female, and non-whites comprised 61% of study subjects. Overnight plaque coverage varied. Mean (SD) plaque area coverage was 16.9% (10.5), ranging from 2.6-39.6%. Calculus was identified at 62% of sites, ranging from 0-100% before prophylaxis. All subjects experienced plaque reductions with prophylaxis, with the minimum plaque area of 0.86% after prophylaxis. Overnight plaque was a significant effect in plaque removal by prophylaxis. Demographic factors and calculus presence/absence did not contribute to the prophylaxis plaque cleaning effect
Conclusion: Use of image analysis demonstrates a high level of between-subject variability in natural plaque accumulation which impacts routine prophylaxis effectiveness.