This in vitro study investigated the erosion-inhibiting properties of dental rinses during erosion in the presence of the salivary pellicle. The erosion inhibition by a Sn/F containing dental rinse (800 ppm Sn(2+), 500 ppm F(-), pH = 4.5) was compared with a fluoridated solution (500 ppm F(-), pH = 4.5) and water (control). Calcium release and enamel softening were significantly reduced among enamel samples exposed to the Sn/F rinse (group SF) compared to those treated with the fluoride solution (group F) and the control (p < 0.05). SEM showed slightly etched enamel interfaces in group SF, whereas the erosion was more pronounced in group F and even more severe in the control group. In conclusion, the Sn/F combination provided the best inhibition of erosion among tested solutions. This study demonstrates the application of different analytical tools for comparative erosion quantification. A strong correlation (r(2) ≥0.783) was shown between calcium release and enamel softening during demineralization.