Toothpastes - pharmacology, Dentin - ultrastructure, Tooth Erosion - pathology, Dentin Desensitizing Agents - pharmacology, Glass - chemistry, Tooth Erosion - physiopathology, Saliva, Artificial - chemistry, Dentin - drug effects, Dentin Permeability - drug effects, Toothbrushing - instrumentation, Ceramics - chemistry, Citric Acid - adverse effects, Biocomp...