Effect of fluoridated toothpicks and dental flosses on enamel and dentine and on plaque composition in situ.

The aim was to evaluate the effect of two toothpicks and two dental flosses on demineralized enamel and dentine and on plaque composition, using an in situ model with simulated approximal spaces within dentures. Fifteen subjects with full dentures were recruited and 14 completed the study. It consisted of two crossover periods, the first comparing a birch toothpick with AmF and a birch toothpick with NaF, and the second comparing a dental floss with AmF + NaF and a dental floss without F. Between these four periods, there was a control period without any approximal cleaning. In small, rectangular sample holders, one enamel and one dentine specimen were embedded, forming a triangular, approximal-like space. Two sample holders were mounted in the premolar-molar region of the upper or lower dentures. The subjects used the toothpicks or dental flosses 3 times/day for 4 weeks. The results showed that all toothpicks and dental flosses inhibited further demineralization compared to the control period (p < 0.001). The dental flosses were somewhat more effective in this respect than the toothpicks, especially in dentine. There were relatively small numerical differences between AmF and NaF toothpicks, but in favour of NaF regarding mineral gain (p < 0.05). The fluoridated floss gave somewhat less lesion depth in dentine than the non-fluoridated floss (p < 0.01). Toothpicks and flosses resulted in lower counts of microorganisms in plaque compared to the control period (p < 0.001); the AmF toothpick gave a more pronounced reduction than the NaF toothpick (p < 0.001).