Fluoride release from fluoride varnish under in vitro and in vivo conditions

Objective: The aim was to investigate the in vitro fluoride release from fluoride varnishes under acidic conditions. Study design: Poly(methyl methacrylate) blocks (Perspex, n=3 per group) were painted with 80±5 mg fluoride varnish (n=10) and placed into artificial saliva for 30min. Then, blocks were placed into either 1% citric acid (pH 2.27) or 0.3% citric acid (pH 3.75) solutions (n=3 per solution and varnish) for 30min with the solutions being replaced every 5min. Saliva and acid solutions were analyzed for fluoride content. Data were analyzed using three-way ANOVA (varnish, solution, time). Results: The three-way interaction was significant (p>0.0001). Fluoride release and release patterns varied considerably between varnishes. Fluoride release in saliva varied by a factor of more than 10 between varnishes. Some varnishes (CavityShield, Nupro, ProFluorid, Vanish) showed higher fluoride release in saliva than during the first 5min of acid exposure, whereas other varnishes (Acclean, Enamel-Pro, MI Varnish, Vella) showed the opposite behavior. There was little difference between acidic solutions. Conclusions: Fluoride release from fluoride varnishes varies considerably and also depends on the dissolution medium. Bearing in mind the limitations of laboratory research, the consumption of acidic drinks after fluoride varnish application should be avoided to optimize the benefit/risk ratio.

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Review of Fluoride Release and Secondary Caries Reduction by Fluoridating Composites

Advances in Dental Research ◽

10.1177/08959374950090040501 ◽

1995 ◽

Vol 9 (4) ◽

pp. 367-376 ◽

Cited By ~ 19

Author(s):

J. Arends ◽

G.E.H.M. Dijkman ◽

A.G. Dijkman

Keyword(s):

Major Part ◽

Fluoride Release ◽

Weak Spot ◽

Secondary Caries ◽

Hard Tissues ◽

Interfacial Gap ◽

Amalgam Restorations

Secondary caries is one of the main reasons to replace restorations. Due to the pressure to eliminate or reduce the number of amalgam restorations in many countries, fluoride-releasing composites have gained in importance. This review limits itself to information relevant to secondary caries near fluoride-releasing anterior or posterior composites. Although many parameters are very important in composite functioning, a weak spot near a filling is always the interface and the locally present interfacial gap between the composite and the hard tissues, where secondary caries takes place due to plaque action. Relevant parameters such as the amount of fluoride released in vitro in μg.cm-2, the rate of fluoride release, and the period of fluoride release are compared for several composites. In vitro F release has been measured for some fluoridating composites for more than five years. Unfortunately, F release in vivo or in situ cannot be measured adequately. The fluoride released by the composites considered is partly taken up by the surrounding tissues, partly released to the saliva, and partly efficacious in possible marginal gaps and defects. A major part of this paper pertains to in vitro, in situ, and in vivo secondary caries reduction experiments. In vitro caries reductions in the order of 40% from F-releasing composites vs. controls have been found. In in situ model investigations under plaque and saliva conditions, secondary caries reduction percentages of between 40 and 50% have been experimentally measured in gaps in enamel near F composites.

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In vitro and in vivo fluoride release from orthodontic elastomeric ligature ties

American Journal of Orthodontics and Dentofacial Orthopedics ◽

10.1016/s0889-5406(99)70331-8 ◽

1999 ◽

Vol 115 (3) ◽

pp. 288-292 ◽

Cited By ~ 22

Author(s):

William A. Wiltshire

Keyword(s):

Fluoride Release

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Studies on the Effect of Fluoride Released by Glass Ionomers in the Oral Cavity

Advances in Dental Research ◽

10.1177/08959374950090040801 ◽

1995 ◽

Vol 9 (4) ◽

pp. 389-393 ◽

Cited By ~ 13

Author(s):

H. Forss ◽

L. Seppä

Keyword(s):

Fluoride Concentration ◽

Mutans Streptococci ◽

In Vitro Studies ◽

Fluoride Content ◽

Fluoride Release ◽

Glass Ionomer ◽

Oral Conditions ◽

Clinical Experiments

Numerous in vitro studies have shown that fluoride released by glass ionomers can have effects on enamel, dentin, and plaque adjacent to the material. However, the action of fluoride in vivo may be different from that found in vitro. The aim of the present series of studies was to investigate the effects of glass ionomers in oral conditions. This was tested in clinical experiments conducted on adults who had freshly made or old glass ionomers in their mouths. The results of the studies showed that fluoride released by glass ionomers may increase the fluoride content of plaque close to the material. Fluoride content decreased rapidly with decreasing fluoride release from glass ionomer, but it was increased slightly even in plaque growing on three-year-old fillings. However, the effect appeared to be very local, and no increase in salivary fluoride content due to glass-ionomer fillings was found. Although the growth of plaque was not inhibited, the proportion of mutans streptococci was significantly reduced in plaque growing on glass ionomer during the six weeks after placement of the material. No such effect, however, could be seen in the case of three-year-old glass-ionomer fillings. Although in vitro studies have shown that glass ionomers can take up fluoride and subsequently release it, applying fluoride gel to old glass-ionomer fillings did not result in an increased fluoride concentration of plaque growing on the fillings in vivo. Further studies are needed to find out whether the recharging of glass ionomers with fluoride has clinical significance.

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Can exposure to acidic beverages following the application of fluoride varnish cause changes in the amount of fluoride release? an in vitro study

Journal of Orofacial Sciences ◽

10.4103/jofs.jofs_33_17 ◽

2017 ◽

Vol 9 (2) ◽

pp. 91

Author(s):

Arathi Rao ◽

Bhaswati Chakraborty ◽

ReshmaK Chandra ◽

Ramya Shenoy ◽

BaranyaS Suprabha

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Fluoride Varnish ◽

Fluoride Release ◽

Acidic Beverages

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Induction and Differentiation of Dental Epithelium in Vivo and in Vitro

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053425 ◽

1982 ◽

Vol 40 ◽

pp. 142-145

Author(s):

E. J. Kollar

Keyword(s):

Connective Tissue ◽

Oral Mucosa ◽

Basal Lamina ◽

Functional Derivatives ◽

Specific Source ◽

Dental Epithelium ◽

Connective Tissue Stroma

The differentiation and maintenance of many specialized epithelial structures are dependent on the underlying connective tissue stroma and on an intact basal lamina. These requirements are especially stringent in the development and maintenance of the skin and oral mucosa. The keratinization patterns of thin or thick cornified layers as well as the appearance of specialized functional derivatives such as hair and teeth can be correlated with the specific source of stroma which supports these differentiated expressions.

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Ultrastructural Correlations between Clonal Human Tumor Colonies and in Vivo Neoplasms

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053711 ◽

1982 ◽

Vol 40 ◽

pp. 210-211

Author(s):

M.J. Murphy ◽

R.R. Price ◽

J.C. Sloman

Keyword(s):

Cultured Cells ◽

Human Tumor ◽

Cell Type ◽

Tumor Mass ◽

Initial Cell ◽

Cloning Assay ◽

Human Tumor Cloning ◽

The Relationship

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.

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Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084120 ◽

1978 ◽

Vol 36 (2) ◽

pp. 650-651

Author(s):

Raul I. Garcia ◽

Evelyn A. Flynn ◽

George Szabo

Keyword(s):

Direct Injection ◽

Skin Pigmentation ◽

Freeze Fracture ◽

Pigment Granule ◽

Time Lapse ◽

Ultrastructural Level ◽

Lanthanum Tracer ◽

A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

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