18 years of using American toothpaste:

The video uses a relatable "before and after" format, humorously exaggerating the negative effects of one product and the positive effects of another to create a strong contrast. The clear reveal of the product responsible for the positive change, coupled with a subtle call to action, makes it highly effective.

The creator contrasts their experience using American toothpaste for 18 years, resulting in "corn teeth," with using Japanese toothpaste for four weeks, which resulted in significantly whiter teeth. The video then reveals the specific toothpaste used daily, "Mouthology 10% Nano-Hydroxyapatite Toothpaste," implying it's responsible for the positive results.