When a dentist tells us something is wrong with our teeth, we tend to follow their advice. But when Mona visits two different dentists, they give her two wildly different diagnoses (with wildly different price tags). So how do we know who's telling the tooth? Mona digs up the dental data to look for answers, and finds that in reality, the study of dentistry is riddled with holes. This is an episode of Am I Normal? with Mona Chalabi, another podcast from the TED Audio Collective. If you like it, you can find all the episodes by following Am I Normal? with Mona Chalabi wherever you're listening to this.