Effect of different concentrations of fluoridated toothpaste on dental erosion

Methods: In a randomised, blinded experiment three groups of seven enamel slabs were cut and mounted into resin blocks, ground and checked for surface flatness using a scanning profilometer (Scantron Proscan 2000). Each slab's surface was covered with nail varnish except for a small window (1x2 mm). Each group was immersed under static conditions for 2 minutes, five times daily in fresh 200 ml aliquots of citric acid 0.3% (pH=3.6). In addition, the slabs were immersed in 3 different toothpastes (0ppm F, 1100ppm F, or 1450ppm F) twice daily, morning and evening, for 2 minutes each time. The total cycling period lasted 16 days. Slabs were incubated overnight and between erosive challenges in artificial saliva at 37oC. A sixty minute gap was left between daytime erosive challenges. Before and after dipping in the erosive solutions the slabs were rinsed with de-ionised water. The slabs were analysed with the scanning profilometer to measure the amount of surface loss at days 4, 8, 12, and 16.

Results: Surface loss increased at all timepoints up to day 16 in all groups, with a maximum increase after day 12. Surface loss ± SD of enamel caused by citric acid combined with using non-fluoridated toothpaste at day 16 was 61.19±8.50 µm, 1100ppm F was 43.44±10.94 µm and 1450ppm F was 34.98±4.29 µm. Treatment differences were statistically significant (CI 95%) for all between product comparisons at day 16.

Conclusion: In this model fluoride toothpastes significantly reduced the progression of dental erosion.