title: Effect of acid-etching on fluoride-treated caries-like lesions of enamel: a SEM study.
abstract: Etching patterns by 20 percent phosphoric acid on caries-like lesions of enamel (white spot) untreated and treated with 0.4 APF were studied at 30, 60, 120 seconds of etch-times using the Scanning Electron Microscope (SEM). The surface topography of acid-etched teeth varied according to the etch time. Acid etching of caries-like lesions treated with fluoride showed etching patterns similar to sound enamel. Based on Silverstone's classification, thirty seconds etch-time produced type III pattern of surface morphology, while type I and type II were observed with 60 and 120 seconds of etch time. Fluoride treated lesions showed increased porosity and in addition to a surface coating of numerous small globules of calcium fluoride. Low level of topical fluoride before sealant application should be beneficial, since this allows a more rapid rate and increased degree of remineralization and possible arrest in the progress of caries lesions.
authors.affiliation: Department of Pedodontics and Preventive Dentistry, College of Dental Surgery, Kasturba Medical College, Manipal, India.
authors.forename: S
authors.initials: S
authors.lastname: Tandon
authors.forename: T A
authors.initials: TA
authors.lastname: Mathew
mesh_terms: D000134:Acid Etching, Dental; D000149:Acidulated Phosphate Fluoride / Q000008:administration & dosage / Q000627:therapeutic use*; D000293:Adolescent; D002124:Calcium Fluoride / Q000737:chemistry; D002327:Cariostatic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002648:Child; D003731:Dental Caries / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D003743:Dental Enamel / Q000187:drug effects* / Q000648:ultrastructure; D003747:Dental Enamel Solubility / Q000187:drug effects; D005460:Fluorides, Topical / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D008855:Microscopy, Electron, Scanning; D010756:Phosphoric Acids / Q000008:administration & dosage / Q000494:pharmacology*; D010895:Pit and Fissure Sealants / Q000627:therapeutic use; D016062:Porosity; D013997:Time Factors; D014089:Tooth Remineralization
chemical_list: D002327:Cariostatic Agents; D005460:Fluorides, Topical; D010756:Phosphoric Acids; D010895:Pit and Fissure Sealants; D000149:Acidulated Phosphate Fluoride; D002124:Calcium Fluoride