The Influence of Plaque on Reaction Mechanism of MFP and NaF in vivo

Abstract

A modified Intra-oral Cariogenicity Test was used to study the influence of plaque on the reaction mechanism of sodium monofluorophosphate (MFP) or sodium fluoride (NaF) in either sound or demineralized enamel in vivo. Volunteer students, wearing mouth appliances holding enamel blocks, rinsed their mouths with MFP or NaF solution (1000 ppm F-) three times a day. The amount of loosely-bound and acquired fluoride was determined after an experimental period of five days in plaque-covered, demineralized (PCD); clean, demineralized (CD); plaque-covered, sound (PCS); and clean sound enamel (CS). While no measurable loosely-bound fluoride could be found after MFP treatment, NaF caused deposition of a significant amount of alkali-soluble fluoride in all experimental groups. After MFP rinses, fluoride concentration in the enamel was increased in the following order: CS, PCS, CD, and PCD. After NaF treatment, demineralized enamel exhibited a higher fluoride acquisition when compared with sound enamel. Plaque had a minor effect on F- acquisition. It is concluded that demineralization of enamel enhances F- uptake from both NaF and MFP solutions. In the presence of plaque, F- acquisition was additionally increased only after MFP rinses in vivo.

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References

Arends, J. ; Nelson, D.G.A. ; Dijkman, A.G. ; and Jonge-Bloed, W.L. (1984): Effect of Various Fluorides on Enamel Structure and Chemistry. In: Cariology Today, Int. Congr. Zurich, 1983, Basel: S. Karger, pp. 245-258.

Bruun, C. and Thylstrup, A. (1983): Whole Saliva Fluoride after Use of NaF and MFP Dentifrices with Various Fluoride Concentrations, Caries Res 17:171.

Caslavska, V. ; Moreno, E.C. ; and Brudevold, F. (1975): Determination of the Calcium Fluoride formed from in vitro Exposure of Human Enamel to Fluoride Solutions, Arch Oral Biol 20:333-339.

Davidson, C.L. ; Arends, J. ; and Hoekstra, J.S. (1965): Density Changes in Enamel after Decalcifications , J Biomechan 9:81-85.

Dijkman, A.G. ; Tak, J. ; and Arends, J. (1982): Fluoride Deposited by Topical Applications in Enamel. KOH-soluble and Acquired Fluoride, Caries Res 16:147-155.

Duff, E.J. (1983): Reaction of Monofluorophosphate with Apatitic Substrates, Caries Res 17 (Suppl. 1):77-90.

Ericsson, Y. (1967): Biological Splitting of P03F Ions, Caries Res 1:144-152.

Hellwig, E. and Klimek, J. (1984): Fluoridverlust aus demineralisiertem Schmelz nach Applikation verschieden konzentrierter NaF und NaMFP Losungen im kunstlichen Mund, Dtsch Zahnärztl Z 39:892-898.

Hellwig, E. ; Klimek, J. ; Schmidt, H.F.M. ; and Egerer, R. (1985): Fluoride Uptake in Plaque-covered Enamel after Treatment with the Fluoride Lacquer Duraphat, J Dent Res 64 :1080-1083.

10.

Ingram, G.S. (1972): Reaction of Monofluorophosphate with Apatite, Caries Res 6:1-15.

11.

Jackson, L.R. (1982): In vitro Hydrolysis of Monofluorophosphate by Dental Plaque Micro-organisms, J Dent Res 61:953-956.

12.

Joyston-Bechal, S. ; Duckworth, R. ; and Braden, M. (1975): Effect of Artificial Plaque on F-Uptake by Human Enamel in vitro, IADR Progr & Abst 54:L 541.

13.

Klimek, J. (1981): Fluoridaufnahme kiinstlicher kariöser Initiallasionen nach Behandlung mit verschiedenen Fluoridverbindungen, Dtsch Zahnärztl Z 36:520-524.

14.

Klimek, J. ; Hellwig, E. ; and Ahrens, G. (1982): Fluoride Taken up by Plaque, by the Underlying Enamel and by Clean Enamel from three Fluoride Compounds in vitro, Caries Res 16 :156-161.

15.

Klimek, J. ; Hellwig, E. ; and Ahrens, G. (1983): Movement of Plaque Fluoride under Cariogenic Conditions , Caries Res 17 :315-320.

16.

Koulourides, T. ; Phantumvanit, P. ; Munksgaard, E.C. ; and Housch, T. (1974): An Intraoral Model used for Studies of

17.

Fluoride Incorporation in Enamel, J Oral Pathol 3:185-195. McNee, S.G. ; Geddes, D.A.M. ; Main, C. ; and Gillespie, F.C. (1980): Measurements of the Diffusion Coefficient of NaF in Human Dental Plaque in vitro, Arch Oral Biol 25:819-823.

18.

Mellberg, J.R. (1980): Penetration of Fluorine from Sodium Monofluorophosphate into Artificially Produced Incipient Enamel Lesions, Caries Res 14:115-120.

19.

Mellberg, J.R. (1983): Monofluorophosphate Utilization in Oral Preparations: Laboratory Observations, Caries Res 17 (Suppl 1): 102- 118.

20.

Pearce, E.I.F. and Jenkins, G.N. (1977): The Decomposition of Monofluorophosphate by Enzymes in Whole Human Saliva, Arch Oral Biol 22:405-407.

21.

Ten Cate, J.M. and Rempt, H.E. (1986): Comparison of the in vivo Effect of a 0 and 1,500 ppm F MFP Toothpaste on Fluoride Uptake, Acid Resistance and Lesion Remineralisation , Caries Res 20:193-201.