Is it true that some people grow three sets of teeth?

Yes, some people do grow three sets of teeth. Humans typically grow two sets of teeth: the primary (or baby) teeth and the permanent teeth. However, in rare cases, a third set of teeth can grow, known as supernumerary teeth. These extra teeth can develop anywhere in the mouth but are most commonly found behind the upper front teeth. Supernumerary teeth can vary in size and shape and may be impacted (stuck in the jawbone) or erupted (visible in the mouth). The exact cause of supernumerary teeth is unknown, but genetics and environmental factors may play a role.