The teeth problem remains one of AI video generation's toughest challenges. Current models tend to render unnaturally perfect, uniform white teeth that look almost artificial. The real giveaway? Watch them during motion—they blur and break down in ways real teeth never do. It's become one of the most reliable visual tells that separates generated content from authentic footage. As video synthesis gets more sophisticated, these small imperfections become increasingly obvious precisely because they're so hard to nail realistically.