Figure 3. Slabs of treated human enamel

Slabs of human enamel treated with a) SnF2 or b) sodium fluoride (NaF), followed by erosive acid challenges. Areas to the left and right of center “trough” treatment areas were protected during erosive challenges and serve as reference control areas. Images c) and d) are cross-sectional microradiographs of thin sections removed from treated enamel specimens, through the area of treatment and acid challenge, showing clear differences in protection provided by SnF2 compared to NaF toothpaste treatment. Note the minimal amount of tooth surface loss in images a) and c), compared to b) and d).