Abstract
Background: There are several brands of fluoride varnishes in the market, but the dynamics of fluoride release from each one might be different. The purpose of this study was to evaluate in vitro the release of fluorides by fluoride varnishes and to determine the correlation with viscosity and wettability.
Material and methods: Forty four enamel blocks 5×5 mm were randomly divided into 4 groups (n=11) ((Duraphat®, Clinpro™ White Varnish, Flúor Protector® and control). We applied 30 milligrams of fluoride varnish to each specimen. The specimens were immersed in a Calcium Phosphate solution at a pH= 6.0. We evaluated the release of fluoride, by using a selective fluoride electrode, during 6 weeks. Viscosity was measured using an Oswald Viscosimeter and the wettability was determined by measuring the contact angle between the varnish and the enamel slab. The statistical analysis was performed using Analysis of variance.
Results: Duraphat showed the highest fluoride release from the second weekend beyond (p<0.001) and Clinpro the greatest rate of release. Duraphat release was the steadiest throughout the experiment. Duraphat showed the highest viscosity and the lowest wettability (p<0.001) and Fluor Protector showed the highest wettability (p<0.001). There was a positive correlation between the release of fluoride and the viscosity and a negative correlation between fluoride release and wettability (r>0.7).
Conclusions: Viscosity and wettability influence the release of fluoride from fluoride varnishes. Key words:Fluorides topical, viscosity, wettability.
Figure 1
Release of fluoride varnishes during 7 days and 6 weeks.
*Read full-text article online at https://pubmed.ncbi.nlm.nih.gov/33680323/
References:
1.Marinho VC, Worthington HV, Walsh T, Clarkson JE. Fluoride varnishes for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2013;7:CD002279. – PubMed
2. Höchli D, Hersberger-Zurfluh M, Papageorgiou SN, Eliades T. Interventions for orthodontically induced white spot lesions: a systematic review and meta-analysis. Eur J Orthod. 2017;39:122–33. – PubMed
3. Lenzi TL, Montagner AF, Soares FZ, de Oliveira Rocha R. Are topical fluorides effective for treating incipient carious lesions?: A systematic review and meta-analysis. J Am Dent Assoc. 2016;147:84–91. – PubMed
4. Ogaard B. The cariostatic mechanism of fluoride. Compend Contin Educ Dent. 1999;20:10–7. – PubMed
5. Castillo JL, Milgrom P, Kharasch E, Izutsu K, Fey M. Evaluation of fluoride release from commercially available fluoride varnishes. J Am Dent Assoc. 2001;132:1389–92. – PubMed
6. Lippert F, Hara AT, Martinez-Mier EA, Zero DT. Laboratory investigations into the potential anticaries efficacy of fluoride varnishes. Pediatr Dent. 2014;36:291–5. – PubMed
7. Bolis C, Hartli GP, Lendenmann U. Fluoride Varnishes – Is There a Correlation Between Fluoride Release and Deposition on Enamel? Oral Health Prev Dent. 2015;13:545–56. – PubMed
8. Professionally-applied and Prescription-strength, Home-use Topical Fluoride Agents for Caries Prevention Clinical Practice Guideline. American Dental Association. 2018. [ cited 10 Jun 2018 ]. [Internet] Available from: http://www.webcitation.org/704ynOprW .
9. Jablonowski BL, Bartoloni JA, Hensley DM, Vandewalle KS. Fluoride release from newly marketed fluoride varnishes. Quintessence Int. 2012;43:221–8. – PubMed
10. Skold-Larsson K, Módeer T, Twetman S. Fluoride concentration in plaque in adolescents after topical application of different fluoride varnishes. Clin Oral Invest. 2000;4:31–4. – PubMed
11. Harding SE. The intrinsic viscosity of biological macromolecules. Progress in measurement, interpretation and application to structure in dilute solution. Prog Biophys Mol Biol. 1997;68:207–62. – PubMed
12. Marshall SJ, Bayne SC, Baier R, Tomsia AP, Marshall GW. A review of adhesion science. Dent Mater. 2010;26:e11–6. – PubMed
13. Shen C, Autio-Gold J. Assessing fluoride concentration uniformity and fluoride release from three varnishes. J Am Dent Assoc. 2002;133:176–82. – PubMed
14. Maas JR, Junior IM, Lodi CS, Delbem AC. Differences in loosely bound fluoride formation and anticaries effect of resin-based fluoride varnishes. Int J Paediatr Dent. 2013;23:166–72. – PubMed
15. Downey D, Dennison J, Eckert GJ, Flannagan SE, Neiva GF, Yaman P. Fluoride Levels in Unstimulated Whole Saliva following Clinical Application of Different 5% NaF Varnishes. Caries Res. 2018;52:431–438. – PubMed
16. Zema L, Maroni A, Foppoli A, Palugan L, Sangalli ME, Gazzaniga A. Different HPMC viscosity grades as coating agents for an oral time and/or site-controlled delivery system: an investigation into the mechanisms governing drug release. J Pharm Sci. 2007;96:1527–36. – PubMed
17. Johansen S, Rask-Pedersen E, Prause JU. An ocular bioavailability comparison in rabbits of prednisolone acetate after repeated topical applications formulated as a high-viscosity gel and as an aqueous suspension. Acta Ophthalmol Scand. 1996;74:259–64. – PubMed
18. Dong Y, Qu H, Pavurala N, Wang J, Sekar V, Martinez MN. Formulation characteristics and in vitro release testing of cyclosporine ophthalmic ointments. Int J Pharm. 2018;544:254–64. – PubMed
19. Saint-Eve A, Martin N, Guillemin H, Sémon E, Guichard E, Souchon I. Flavored yogurt complex viscosity influences real-time aroma release in the mouth and sensory properties. J Agric Food Chem. 2006;54:7794–803. – PubMed
20. S, Shire SJ, Kalonia DS. Viscosity analysis of high concentration bovine serum albumin aqueous solutions. Pharm Res. 2011;28:1973–83. – PubMed
21. Pichaiaukrit W, Thamrongananskul N, Siralertmukul K, Swasdison S. Fluoride varnish containing chitosan demonstrated sustained fluoride release. Dent Mater J. 2019;38:1036–42. – PubMed
22. Yang B, Wei C, Qian F, Li S. Surface Wettability Modulated by Surfactant and Its Effects on the Drug Release and Absorption of Fenofibrate Solid Dispersions. AAPS PharmSciTech. 2019;20:234. – PubMed
23. Dredán J, Fekete R, Zelkó R, Rácz I, Marton S. Effect of the wettability characteristics of polyethylene glycol derivatives on the drug release of wax matrices. Pharmazie. 2000;55:925–7. – PubMed
24. Park MS, Chung JW, Kim YK, Chung SC, Kho HS. Viscosity and wettability of animal mucin solutions and human saliva. Oral Dis. 2007;13:181–6. – PubMed
*Read full-text article online at https://pubmed.ncbi.nlm.nih.gov/33680323/
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