Figure 6

An enamel crack was arrested at interglobular porous space (IGS) region analyzed by using TXM.
A deep enamel crack observed in an extant Caiman Crocodilus tooth was arrested inside the IGS region rather than at the DEJ boundary. Because, the IGS is a kind of randomly distributed porous structure that may help redirect crack propagation and release the stress. The results also demonstrated that the high-resolution TXM image can help us identify the crack-arrested site or crack trajectory in teeth much more clearly.