title: The effect of time of topical application of fluorides on the hardness of etched and un-etched enamel surfaces.
mesh_terms: D000134:Acid Etching, Dental; D001840:Dental Bonding; D003743:Dental Enamel / Q000187:drug effects*; D005460:Fluorides, Topical / Q000494:pharmacology*; D006244:Hardness; D006801:Humans; D066298:In Vitro Techniques; D013997:Time Factors
chemical_list: D005460:Fluorides, Topical