Methods: Plaque distribution on mesial, distal and labial surfaces of incisors and canines (36 surfaces per person) in 7 males (26-37 years old) were analyzed by QLF-D. And then, their plaque distribution was evaluated by traditional staining method using 2 Tone (Young Manufacturing, Earth City, USA). Examination outcomes were compared between the two methods. Additionally, longitudinal plaque distribution in the same areas as described above was evaluated. Incisors and canines in 3 males were cleaned. After 0, 24 and 48 hours after teeth cleaning, plaque distribution in the area was evaluated using QLF-D. They spent time without teeth cleaning and brushing throughout the experiment period.
Results: Plaque was found in both methods on 81 surfaces (32.1% of evaluated surfaces). Besides, plaque was not found in both methods on 89 surfaces (35.3%). Plaque was found only by QLF-D on 55 surfaces (21.8%), on the other hand, plaque was found by only traditional method on 27 surfaces (10.7%). These results indicated that traditional method failed in detecting plaque in 21.8% of the evaluated surfaces, on the other hand, QLF-D failed in detecting plaque only in 10.7% of the evaluated surfaces. In the longitudinal evaluation of plaque distribution, plaque began to grow near gingival margin and mesial and distal surfaces.
Conclusions: QLF-D is a valuable means of evaluating plaque distribution.