title: Effect of ammonium hexafluorosilicate application for arresting caries treatment on demineralized primary tooth enamel.
abstract: Ammonium hexafluorosilicate (AHF) has been applied to arrest caries without discoloration. The purpose of this study was to observe structural and elemental changes of demineralized and AHF applied primary tooth enamel. Enamel from the labial surface of 20 primary canines was divided into an unground side and ground side at the center of the tooth, and demineralized with 35% phosphoric acid for 6 min. The teeth were divided into 4 groups according to a 3-min application of AHF and 1 week of soaking in artificial saliva, as follows: group A (neither AHF nor saliva), group B (only saliva), group C (only AHF), and group D (AHF and saliva), and then subdivided according to whether the enamel was ground or unground. Specimens were analyzed with scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). The data were statistically analyzed using ANOVA and Fisher's PLSD test at α = 0.05. In groups A and B, prism structures were seen, however, in groups C and D, enamel surfaces were covered with spherical particles. Ca/P ratio was significantly higher in groups C and D than in groups A and B. There was no significant difference between ground and unground enamel in the content of any element. The values for F, Na, Mg and Si persents and Ca/P ratio were significantly higher for the enamel surface than for points 10-30 µm beneath the surface. Results of this study suggest the possibility that AHF treatment arrests caries, although further study will be required to confirm this result.
authors.affiliation: Department of Pediatric Dentistry, Course of Medical and Dental Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan. hosoya@nagasaki-u.ac.jp
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Hosoya
authors.forename: Katsumi
authors.initials: K
authors.lastname: Tadokoro
authors.forename: Hideji
authors.initials: H
authors.lastname: Otani
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Hidaka
authors.forename: Takashi
authors.initials: T
authors.lastname: Inoue
authors.forename: Masashi
authors.initials: M
authors.lastname: Miyazaki
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
mesh_terms: D002118:Calcium / Q000032:analysis; D002326:Cariogenic Agents / Q000009:adverse effects; D002327:Cariostatic Agents / Q000627:therapeutic use*; D003481:Cuspid / Q000187:drug effects / Q000648:ultrastructure; D003743:Dental Enamel / Q000187:drug effects* / Q000648:ultrastructure; D005459:Fluorides / Q000032:analysis / Q000627:therapeutic use*; D006801:Humans; D008274:Magnesium / Q000032:analysis; D008855:Microscopy, Electron, Scanning; D010756:Phosphoric Acids / Q000009:adverse effects; D010758:Phosphorus / Q000032:analysis; D012464:Saliva, Artificial / Q000494:pharmacology; D012824:Silicic Acid / Q000627:therapeutic use*; D012825:Silicon / Q000032:analysis; D012964:Sodium / Q000032:analysis; D013052:Spectrometry, X-Ray Emission; D017001:Tooth Demineralization / Q000517:prevention & control*; D014089:Tooth Remineralization / Q000379:methods*; D014094:Tooth, Deciduous / Q000187:drug effects* / Q000648:ultrastructure
chemical_list: D002326:Cariogenic Agents; D002327:Cariostatic Agents; D010756:Phosphoric Acids; D012464:Saliva, Artificial; D012824:Silicic Acid; C004832:hexafluorosilicate; D010758:Phosphorus; D012964:Sodium; C030242:phosphoric acid; D008274:Magnesium; D005459:Fluorides; D002118:Calcium; D012825:Silicon