title: Sampling of porous hard tissues in vitro by acid etching.
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods*; D001031:Apatites; D001842:Bone and Bones / Q000032:analysis*; D004396:Coloring Agents; D001840:Dental Bonding / Q000379:methods*; D003731:Dental Caries / Q000378:metabolism; D003804:Dentin / Q000032:analysis; D005459:Fluorides / Q000032:analysis; D006801:Humans; D008689:Methacrylates; D010710:Phosphates / Q000032:analysis; D013048:Specimen Handling / Q000379:methods*; D014070:Tooth / Q000032:analysis*
chemical_list: D001031:Apatites; D004396:Coloring Agents; D008689:Methacrylates; D010710:Phosphates; D005459:Fluorides