This rupture of the bond causes the formation of spaces, which serve as a port of entry to bacteria and their products, leading to secondary caries, marginal stains, pulp inflammation and hypersensitivity to cold (72,73). Due to the deficient seal at the tooth/restoration interface, the free extremities of the tubules are exposed, generating a flow of fluids due to differences in gradient when they come into contact with the external medium (16).