This paper reviews the use of Intraoral model systems to help elucidate the role of fluoride and. its mechanism of action in caries prevention. The Intraoral models currently in use were found to be of three general types. The most widely used system has consisted of a removable appliance that relies on the use of dacron gauze or a recessed sample to enhance plaque formation. Similarly, the banding model of Øgaard requires the presence of orthodontic band material to produce a plaque accumulation niche for demineralization, while the crown single-section technique relies mainly on placement of the sections in plaque-retentive areas (below contact points). In general, the models may be used for the assessment of food cariogenicity, an evaluation of de- and re-mineralization, and measurement of fluoride incorporation into enamel or root substrates.
On evaluation of lesion initiation and progression in vivo, it is apparent that few non-destructive in vivo techniques are available that offer the sensitivity of laboratory-based analysis. Thus, the use of Intraoral models that allow lesion formation and progression to occur in the oral environment, but can be measured with the sensitivity of in vitro techniques, has been extremely important. Although the magnitude of the fluoride dose, the longevity of fluoride in the oral environment, and the time required for remineralization are different from those found in vitro, it is apparent that the presence of fluoride in the aqueous phase is now thought to be of primary importance. Mechanistically, the presence of fluoride will both inhibit demineralization by acid and promote remineralization under more neutral conditions. Thus, one of fluoride's major contributions is to affect the rates of lesion formation and progression. It was concluded that low-concentration fluoride agents with a high frequency of application would best fulfill the above needs.
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References
1.
ALMQUISTH.; WEFELJ.S.; LAGERLÖFF.; EKSTRANDJ.; and HENRIKSONC.O. (1987): Root Caries Progression in vitro Using 125I Absorptiometry, J Dent Res66: 346, Abst. No. 1919.
2.
ALMQUISTH.; WEFELJ.S.; LAGERLÖFF.; EKSTRANDJ.; and HENRIKSONC.O. (1988): In vitro Root Caries Progression Measured by 125I Absorptiometry. Comparison with Chemical Analysis, J Dent Res67: 1217–1220.
3.
AMJADA., and NANCOLLASG.H. (1979): Effect of Fluoride on the Growth of Hydroxyapatite and Human Dental Enamel, Caries Res13: 250–258.
4.
ARENBERGP.; ØGAARDB.; SCHEIEA.A.; and RØLLAG. (1984): Selection of Streptococcus mutans and Lactobacilli in an Intraoral Human Model, J Dent Res63: 1197–1200.
5.
ARENDSJ., and CHRISTOFFERSENJ. (1986): The Nature of Early Caries Lesions in Enamel, J Dent Res65: 2–11.
6.
ARENDSJ., and GELHARDT.B.F.M. (1983): In vivo Remineralization of Human Enamel. In: Demineralisation and Remineralisation of the Teeth, LeachS.A., and EdgarW.M., Eds., Oxford: IRL Press, Ltd., pp. 1–16.
7.
ARENDSJ., and GELHARDT. (1984): Enamel Remineralization in vivo. In: Tooth Enamel IV, FearnheadR.W., and SugaS., Eds., Amsterdam: Elsevier Science Publishers, pp. 321–325.
8.
ARENDSJ., and TEN BOSCHJ.J. (1986): In vivo Remineralization of Dental Enamel. In: Factors Relating to Demineralisation and Remineralisation of the Teeth, LeachS.A., Ed., Oxford: IRL Press, Ltd., pp. 1–11.
BRUDEVOLDF.; ATTARZADEHF.; TEHRANIA.; VAN HOUTEJ.; and RUSSOJ. (1984): Development of a New Intraoral Demineralization Test, Caries Res18: 421–429.
11.
CLARKJ.W.; MOREF.G.; CORPRONR.E.; KORYTNICKIC.J.; and KOWALSKIC.J. (1986): Effects on Artificial Enamel Lesions in vivo by Exposure to NaF Lozenges, Caries Res20: 465–472.
12.
CLARKSONB.H.; FEJERSKOVO.; SILVERSTONEL.M.; and EKSTRANDJ. (1986): Rational Use of Fluorides in Caries Prevention and Treatment. In: Fluoride in Dentistry, EkstrandJ., FejerskovO., and SilverstoneL.M., Eds., Copenhagen: Munksgaard, pp. 276–288.
13.
CORPRONR.E.; MOREF.G.; CLARKJ.W.; KORYTNICKIC.J.; and KOWALSKIC.J. (1986): In vivo Remineralization of Artificial Enamel Lesions by a Fluoride Dentifrice or Mouthrinse, Caries Res20: 48–55.
14.
CREANORS.L.; MacFARLANET.W.; MacKENZIED.; WEETMAND.A.; STRANGR.; and STEPHENK.W. (1986a): Microbiology and Acid/Anion Profiles of Enamel Surface Plaque from an in situ Caries Appliance, Caries Res20: 392–397.
15.
CREANORS.L.; STRANGR.; TELFERS.; MacDONALDI.; SMITHM.J.; and STEPHENK.W. (1986b): In situ Appliance for the Investigation of Enamel and De- and Remineralization, Caries Res20: 385–391.
16.
DE BRUYNH.; HUMMELM.; and ARENDSJ. (1985): In vivo Effect of a Fluoridating Varnish with Various Fluoride Contents on Human Enamel, Caries Res19: 407–413.
17.
DE KLOETH.J.; EXTERKATER.A.M.; REMPTH.E.; and TEN CATEJ.M. (1986): In vivo Bovine Enamel Remineralization and Fluoride Intake from Two Dentifrices Containing Different Fluoride Concentrations, J Dent Res65: 1410–1414.
18.
DIJKMANA.G.; SCHUTHOFJ.; and ARENDSJ. (1986): In vivo Remineralization of Plaque-induced Initial Enamel Lesions—A Microradiographic Investigation, Caries Res20: 202–208.
19.
FEATHERSTONEJ.D.B.; CUTRESST.W.; RODGERSB.E.; and DENNISONP.J. (1982): Remineralization of Artificial Caries-Like Lesions in vivo by a Self-Administered Mouthrinse or Paste, Caries Res16: 235–242.
20.
FEATHERSTONEJ.D.B.; McINTYREJ.M.; and FuJ. (1987): Physico-Chemical Aspects of Root Caries Progression. In: Dentine and Dentine Reactions in the Oral Cavity, ThylstrupA., LeachS.A., and QuistV., Eds., Oxford: IRL Press, Ltd., pp. 127–137.
21.
FEATHERSTONEJ.D.B.; O'REILLYM.M.; SHARIATIM.; and BRUGLERS. (1986): Enhancement of Remineralisation in vitro and in vivo. In: Factors Relating to Demineralisation and Remineralisation of the Teeth, LeachS.A., Ed., Oxford: IRL Press Ltd., pp. 23–34.
22.
FEATHERSTONEJ.D.B.; TEN CATEJ.M.; SHARIATIM.; and ARENDSJ. (1983): Comparison of Artificial Caries-Like Lesions by Quantitative Microradiography and Microhardness Profiles, Caries Res17: 385–391.
23.
FEJERSKOVO.; THYLSTRUPA.; and LARSENM.J. (1981): Rational Use of Fluorides in Caries Prevention—A Concept Based on Possible Mechanisms, Acta Odontol Scand39: 241–247.
24.
GELHARDT.B.F.M., and ARENDSJ. (1984a): In vivo Remineralization of Artificial Subsurface Lesions in Human Enamel. I, J Biol Buccale12: 49–57.
25.
GELHARDT.B.F.M., and ARENDSJ. (1984b): Microradiography of in vivo Remineralized Lesions in Human Enamel. II, J Biol Buccale12: 59–65.
26.
GELHARDT.B.F.M.; TEN CATEJ.M.; and ARENDSJ. (1979): Rehardening of Artificial Enamel Lesions in vivo, Caries Res13: 80–83.
27.
HARGREAVESJ.A.; THOMPSONG.W.; and WAGGB.J. (1983): Changes in Caries Prevalence of Isle of Lewis Children Between 1971 and 1981, Caries Res17: 554–559.
28.
HAYESP.A., and WEFELJ.S. (1988): In vivo Remineralization of Enamel at the Buccal and Proximal Sites Using Two Fluoride Regimens, J Am Acad Ped Dent10: 295–300.
29.
HOLMENL.; THYLSTRUPA.; ØGAARDB.; and KRAGHF. (1985a): A Polarized Light Microscopic Study of Progressive Stages of Enamel Caries in vivo, Caries Res19: 348–354.
30.
HOLMENL.; THYLSTRUPA.; ØGAARDB.; and KRAGHF. (1985b): A Scanning Electron Microscope Study of Progressive Stages of Enamel Caries in vivo, Caries Res19: 355–367.
31.
JULINP. (1975): Quantitative Longitudinal Photon Absorptiometry in vitro on Changes in Enamel Mineral Loss. Thesis, Odontolog-ical Faculty, Karolinska Institutet, Stockholm, Sweden.
32.
KOTSANASN.; DARLINGA.I.; and LEVERSB.G.H. (1986): A Model for the Production of Artificial Caries in the Mouth in Man, Arch Oral Biol37: 491–495.
33.
KOULOURIDEST. (1980): Increasing Tooth Resistance to Caries Through Remineralization. In: Foods, Nutrition, and Dental Health, HefferrenJ.J., and KoehlerH.M., Eds., Chicago: Am Dent Assoc., pp. 193–207.
34.
KOULOURIDEST. (1986): Implications of Remineralization in the Treatment of Dental Caries, Higashi Nippon Dent J5: 1–20.
35.
KOULOURIDEST.; BODDENR.; KELLERS.; MANSON-HINGL.; LASTRAJ.; and HOUSCHT. (1976): Cariogenicity of Nine Sugars Tested With an Intraoral Device in Man, Caries Res10: 427–441.
36.
KOULOURIDEST., and HOUSCHT. (1983): Hardness Testing and Microradiography of Enamel in Relation to Intraoral De- and Remineralisation. In: Demineralisation and Remineralisation of the Teeth, LeachS.A., and EdgarW.H., Eds., Oxford: IRL Press, Ltd., pp. 255–272.
37.
KOULOURIDEST.; PHANTUMVANITP.; MUNKSGAARDE.C.; and HOUSCHT. (1974): An Intraoral Model Used for Studies of Fluoride Incorporation in Enamel, J Oral Pathol3: 185–195.
38.
KOULOURIDEST., and VOLKERJ.F. (1964): Changes of Enamel Microhardness in the Human Mouth, Ala J Med Sci1: 435–437.
39.
LAMBROUD.; LARSONM.J.; FEJERSKOVO.; and TACHOSB. (1981): The Effect of Fluoride in Saliva on Remineralization of Dental Enamel in Humans, Caries Res15: 341–345.
40.
LARSENM.J., and FEJERSKOVO. (1977): Surface Etching and Subsurface Demineralization of Dental Enamel Induced by a Strong Acid, Scand J Dent Res85: 320–326.
41.
MELLBERGJ.R., and CHOMICKIW.G. (1983): Fluoride Uptake by Artificial Caries Lesions from Fluoride Dentifrices in vivo, J Dent Res62: 540–542.
42.
MOBLEYM.J. (1981): Fluoride Uptake From in situ Brushing with a SnF2 and a NaF Dentifrice, J Dent Res60: 1943–1948.
43.
NYGAARD ÖSTBYB.; MÖRCHT.; and HALSE. (1957): A Method for Caries Production in Selected Tooth Surfaces in vivo— Employed in a Preliminary Study of the Caries-inhibiting Effect on Topically Applied Agents, Acta Odontol Scand15: 357–363.
44.
ØGAARDB.; ARENDSJ.; SCHUTHOFJ.; RØLLAG.; EKSTRANDJ.; and OLIVEBYA. (1986): Action of Fluoride on Initiation of Early Enamel Caries in vivo, Caries Res20: 270–277.
45.
ØGAARDG.; RØLLAG.; and ARENDSJ. (1988): In vivo Progress of Enamel and Root Surface Lesions Under Plaque as a Function of Time, Caries Res22: 302–305.
46.
ØGAARDB.; RØLLAG.; and HELGELANDK. (1983): Alkali Soluble and Alkali Insoluble Fluoride Retention in Demineralized Enamel in vivo, Scand J Dent Res91: 200–204.
47.
OSTROMC.A.; KOULOURIDEST.; RETIEFD.H.; and BRADLEYE.L. (1984): Enamel Fluoride Uptake and Acid Resistance in Subjects with High and Low Experimental Cariogenicity, J Dent Res63: 133–136.
48.
PHANKOSOLP.; ETTINGERR.L.; HICKSM.J.; and WEFELJ.S. (1985): Depth of Penetration of in vitro Root Surface Lesions, J Dent Res64: 897–899.
49.
REINTSEMAH., and ARENDSJ. (1988): An in vivo Study of Microhardness and Fluoride Uptake in Partially Demineralized Human Enamel Covered by Plaque, J Dent Res67: 471–473.
50.
REINTSEMAH.; SCHUTHOFJ.; and ARENDSJ. (1985): An in vivo Investigation of the Fluoride Uptake in Partially Demineralized Human Enamel from Several Dentifrices, J Dent Res64: 19–23.
51.
STOOKEYG.K.; SCHEMEHORNB.R.; CHEETHAMB.L.; WOODG.D.; and WALTONG.V. (1985): In situ Fluoride Uptake from Fluoride Dentifrices by Carious Enamel, J Dent Res64: 900–903.
52.
TEN CATEJ.M., and REMPTH.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 Remineralization, Caries Res20: 193–201.
53.
THEUNSH.M. (1986): Lesion Formation in Abraded Human Enamel, Caries Res20: 510–517.
54.
VON DER FEHRF.R. (1961): The Effect of Fluorides on the Caries Resistance of Enamel, Acta Odontol Scand19: 431–442.
55.
VON DER FEHRF.R. (1965): Maturation and Remineralization of Enamel, Adv Fluorine Res3: 83–95.
56.
VON DER FEHRF.R. (1967): A Study of Carious Lesions Produced in vivo in Unabraded, Abraded, Exposed, and F-Treated Human Enamel Surfaces with Emphasis on the X-Ray Dense Outer Layer, Arch Oral Biol12: 797–814.
57.
VON DER FEHRF.R.; LÖEH.; and THEILADEE. (1970): Experimental Caries in Man, Caries Res4: 131–148.
58.
WEFELJ.S.; HOGANM.M.; KRELLD.D.; and JENSENM.J. (1987a): Intraoral Lesion Formation in Root Surfaces, J Dent Res66: 217, Abst. No. 885.
59.
WEFELJ.S.; JENSENM.E.; and HOGANM.M. (1986a): Intraoral Lesion Formation in Enamel and Root Surfaces, Caries Res21:172 (Abst. 38).
60.
WEFELJ.S.; MAHARRYG.J.; and JENSENM.J. (1988): In situ Remineralization with Fluoride Rinses, J Dent Res67: 192, Abst. No. 639.
61.
WEFELJ.S.; MAHARRYG.; JENSENM.E.; and HARLESSJ.D. (1987b): Development of an Intraoral Single-section Remineralization Model, J Dent Res66: 1485–1489.
62.
WEFELJ.S.; MAHARRYG.; JENSEN,.M.E.; HAYESP.; and CLARKSONB.H. (1986b): In vivo Demineralisation and Remineralisation of Enamel and Root Surfaces. In: Factors Relating to Demineralisation and Remineralisation of the Teeth, LeachS.A., Ed., Oxford: IRL Press, Ltd., pp. 181–190.
63.
ZIMMERMANM.B.; KOULOURIDEST.; MUHAMMADN.A.; CORPRONW.I.; HIGUCHIW.I.; and KOWALSKIC.J. (1985): Intraoral Uptake of Fluoride by Presoftened Enamel Following Systemic Administration and Fluoride Mouthrinsing, Caries Res19: 255–261.
