| pubmed-article:2490984 | pubmed:abstractText | Enamel blocks of 16mm2 from pre-molars buccal surface, extracted by orthodontics reasons, were prepared for scanning electron microscope study. No treated surfaces displayed the characteristics of normal surface--young, with no defects, presence of perikemata and their pits and depressions. The effects of etching and polishing with abrasive paste were evidenced. Treated samples were enamel blocks demineralized and previously polished; they were given topical application of NaF (pH 4.6); APF (pH 3.2) and NH4F (pH 4.6) by 5 minutes. The control site was protected with nail lacquer to avoid the solution test contact. After treatment the blocks were submitted to KOH extraction, to remove calcium fluoride accumulated on the surfaces. Similar degrees of demineralization were observed, whereas the NH4F treatment have shown a more significant pattern. | lld:pubmed |
