Puffers belong to the family
Diodontidae ("fused tooth"), the porcupinefishes and burrfishes. The family name refers to the fused beak-like teeth these fishes display. The teeth are used for the rendering of their prey items into consumable foods (snails, bivalves, echinoderms, crustaceans, etc). Such a consumption of hard materials wears the teeth down fairly rapidly, such that these creatures have evolved teeth that are replaced from the dental base by continuous growth. In order for these fishes to wear these teeth down in the absence of hard prey, they will graze the surface of live rock, hard substrates, or coral to wear down these teeth. Depending on your specimen and the foods offered, they may or may not be problematic with
stony corals in captive systems. The occasional feeding of whole live clams or oysters may prevent the coral-consumption activity.
Too bad
Scott Michael doesn't come by here on occasion, I understand these are some of his favorite fishes.