Effect of fluoride containing dentifrice, mouthrinsing, and varnish on approximal dental caries in a 3-year clinical trial

Comparative Evaluation of the Remineralizing Potential of Silver Diamine Fluoride, Casein Phosphopeptide-amorphous Calcium Phosphate, and Fluoride Varnish on the Enamel Surface of Primary and Permanent Teeth: An In Vitro Study

Introduction

With the paradigm shift in the management of dental caries, the focus is now laid on remineralization therapies that can arrest the progression of the disease and remineralize the subsurface lesions.

Objectives

The purpose of this study was to determine and compare the remineralizing potential of silver diamine fluoride (SDF), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), and fluoride varnish (FV) on enamel surfaces in primary and permanent teeth.

Materials and methods

A total of 120 primary anterior teeth and 120 premolars were used to prepare enamel blocks in acrylic resin. The mean baseline surface microhardness (SMH) for each sample was determined using a microvickers hardness testing machine. Thereafter, the samples were randomly and equally distributed into groups and subgroups based on the materials used, that is, SDF, CPP-ACP, FV, and distilled water (control). After subjecting the samples to a pH cycling regime, SMH was determined again and the percentage change in SMH was calculated.

Results

The data were tabulated and subjected to statistical analysis using an independent t-test and one-way analysis of variance (ANOVA). In primary teeth, the least mean percentage reduction in SMH was observed after the application of FV followed by SDF, CPP-ACP, and control. In permanent teeth, both SDF and FV showed the least percentage reduction of enamel SMH followed by CPP-ACP and control.

Conclusion

Silver diamine fluoride (SDF), FV, and CPP-ACP showed remineralizing potential in both primary and permanent teeth.

How to cite this article

Kaur S, Bhola M, Bajaj N, et al. Comparative Evaluation of the Remineralizing Potential of Silver Diamine Fluoride, Casein Phosphopeptide-amorphous Calcium Phosphate, and Fluoride Varnish on the Enamel Surface of Primary and Permanent Teeth: An In Vitro Study. Int J Clin Pediatr Dent 2023;16(S-1):S91-S96.

Effect of a mouth rinse and a high-fluoride toothpaste on caries incidence in orthodontic patients: A randomized controlled trial

INTRODUCTION

The objective was to evaluate the effect of a fluoride mouth rinse and a high-fluoride toothpaste on caries incidence in patients undergoing orthodontic treatment with fixed appliances.

METHODS

In this 3-armed, parallel-group, randomized controlled trial, patients referred to the Specialist Clinic of Orthodontics, Mölndal, Sweden, were randomly allocated to 1 of the 3 groups. (1) Fluoride mouth rinse (FMR) group: 0.2 % sodium fluoride (NaF) mouth rinse plus 1450 ppm fluoride (F) toothpaste; (2) High-fluoride tootpaste (HFT) group: 5000 ppm F toothpaste; and (3) Control (CTR) group: 1450 ppm F toothpaste. The generation of a randomization sequence was performed in blocks of 30. Inclusion criteria included patients scheduled for treatment with fixed appliances in the maxillary and mandibular arch aged 12-20 years. The primary outcome variable was the change in Decayed Initial Filled Surfaces (ΔDiFS) based on radiographs taken before and after the treatment. For statistical comparisons between groups, the Kruskal-Wallis test were used for continuous variables, whereas the Mann-Whitney U-test was used for pairwise group comparisons. Furthermore, the risk ratio (RR) and 95% confidence interval (CI) based on clinically relevant cutoffs (DiFS ≥2) were calculated to compare the increase of caries during orthodontic treatment between 2 groups. The Cochran-Mantel-Haenszel method was used to adjust RR for baseline values. Blinding was employed during the caries registration and the data analysis.

RESULTS

In total, 270 participants were randomized, with 15 patients dropping out, such that 255 patients were included in the statistical analyses. Recruitment was from October 2010 to December 2012. An increase in DiFS (≥1 DiFS) during treatment was observed in 48.3% of the FMR group, 42.0% of the HFT group, and 35.6% of the CTR group. There was no significant difference between the groups regarding increased DiFS (P = 0.17). The risk of increase in DiFS ≥2 during orthodontic treatment was 31.0% in the FMR group, 25.9% in the HFT group, and 18.4% in the CTR group. The RR for an increase of ≥2 DiFS during orthodontic treatment was 1.38 (95% CI, 0.81-2.34; P = 0.23) for FMR vs CTR, 1.21 (95% CI, 0.70-2.10; P = 0.51) for HFT vs CTR, and 0.93 (95% CI, 0.57-1.49; P = 0.76) for HFT vs FMR.

CONCLUSIONS

In patients who demonstrate a low prevalence of caries and are undergoing orthodontic treatment, daily use of high-fluoride toothpaste or fluoride mouth rinse in combination with regular toothpaste does not appear to significantly alter the caries incidence compared with the use of regular toothpaste.

TRIAL REGISTRATION

The trial was registered in the FoU i Sverige research database (http://www.fou.nu/is/sverige), with registration no. 236251.

PROTOCOL

The protocol was not published before trial commencement.

FUNDING

Local Research and Development Board for Gothenburg and South Bohuslän (grant no. 768531); and The Swedish Patent Revenue Fund (grant number EKF-780/19).

Caries increment and prediction from 12 to 18 years of age: A follow-up study

AIM

This was to determine the increment of caries from 12 to 18 years of age and to explore the possibility of predicting caries increment in this period based on the caries experience at age 12 years.

STUDY DESIGN

Prospective longitudinal survey.

METHODS

A sample of 12-year-old children (n =159) were examined in 1993 and 70% of them re-examined at 18 years of age. Bitewing radiographs were taken and a diagnostic system using five caries grades (D(1) to D D(5)) was used at both ages. Children at risk were defined as those who developed manifest caries lesions (D(3-5)FS) on approximal surfaces during the follow-up period. Possible predictors were analysed by calculation of sensitivity, specificity, efficiency of the test, proportion that tested positive and actual proportion of the population at risk.

RESULTS

The mean caries increment (D(1-5)MFS) from 12 to 18 years of age was 4.2 (SD +/- 9.1). The percentage of caries-free adolescents at 12 and 18 years of age was 10% and 1% respectively; 25% had either a reversal or no increment in caries experience while the D(1-5)MFS increased in 65% of the adolescents. Of the increment of manifest lesions (D(3-5)FS), 18% were located in incisors/canines, 40% in premolars, 26% in first molars and 16% in second molars. Premolars had the largest proportion of the approximal surfaces with manifest caries increment. The best predictors of children at risk of approximal caries increment (D(3-5)FS) were caries experience (D(1-5)FS) on the approximal surfaces of premolars and second molars at the age of 12 years. The individuals that developed four or more manifest lesions on approximal surfaces between 12 and 18 years were the easiest to predict (sensitivity + specificity = 175%).

CONCLUSIONS

There was a considerable increment of manifest caries lesions from 12 to 18 years of age in all tooth groups. The best predictors for increment of manifest caries on approximal surfaces during the age period were approximal caries in premolars and second molars at the age of 12 years.

Effect of different frequencies of fluoride dentifrice and mouthrinse administration: an in situ study

The effect of a combination of topical fluoridation methods for inhibition of enamel demineralization in the face of a cariogenic challenge has not been clearly established. This in situ crossover study aimed to assess whether the addition of daily use of fluoride mouthrinse (FR) to that of fluoride dentifrice (FD) is equivalent to increasing the frequency of FD application in terms of the effect on enamel demineralization and fluoride content. Over 3 phases of 14 days each, 12 volunteers wore appliances containing enamel blocks exposed to a 20 % sucrose solution 8 times/day. During each phase the blocks underwent one of the following treatments: 2x/day FD, 2x/day FD + 1x/day FR, and 3x/day FD. The blocks were assessed for hardness and fluoride content. Three x/day FD did not differ from 2x/day + 1x/day FR, however it enhanced demineralization protection when compared to 2x/day FD. All treatments produced an increase in enamel fluoride content compared to no treatment (sound blocks) (p < 0.05), but the differences between them were not significant. The results of this study suggest that the daily use of fluoride mouthrinse combined with that of fluoride dentifrice has similar effects on enamel demineralization and fluoride content when compared to increasing the frequency of fluoride dentifrice use.

Randomized equivalence trial of intensive and semiannual applications of fluoride varnish in the primary dentition

For children in the primary dentition with high caries prevalence the standard semiannual application of fluoride varnish may not be successful in preventing tooth decay. Oftentimes this population is mobile and does not receive consistent preventive care. This trial tested whether an intensive fluoride 5% sodium varnish regimen (three applications/2 weeks) applied annually has an equivalent effect on caries progression in the primary dentition compared to single applications applied semiannually. This study was a randomized clinical trial with two treatment groups. All participants (n = 600; mean age +/- SD = 55.3 +/- 4.6 months) received three varnish applications (active varnish or placebo) at semiannual visits over 3 years. Once per year the intensive-treatment group received one set of three active treatments and three placebo treatments 6 months later, each time within 2 weeks. The standard group received one active and two placebo treatments every 6 months. Children were assessed clinically at baseline and 12, 24 and 36 months after the initiation of the study. The mean (SD) numbers of newly decayed primary tooth surfaces observed over 3 years were 9.8 (8.6) and 7.4 (7.7) in the intensive and standard groups, respectively. The adjusted rate ratio was 1.13 (95% CI = 0.94-1.37, p = 0.20). In conclusion, the trial failed to demonstrate clear evidence of a difference in efficacy. However, differences of up to 36% greater rates of caries in the intensive group could not be ruled out, thus equivalence of the treatments cannot be concluded.

Approximal Caries Development in Adolescents with Low to Moderate Caries Risk after Different 3-Year School-Based Supervised Fluoride Mouth Rinsing Programmes

The aim was to evaluate a 3-year randomised controlled trial of school-based fluoride mouth rinsing (FMR) on approximal caries development in 13- to 16-year-olds with low to moderate caries risk. The adolescents used F toothpaste at home and underwent prophylactic treatment at yearly check-ups at public dental clinics. Out of 788 randomly selected 13-year-olds, 622 completed the trial, carried out in 1999-2003. Supervised by a dental nurse, the subjects rinsed with a 0.2% NaF solution at different intervals. Group 1 rinsed their teeth on the first three schooldays every semester; group 2 on the first three and the last three schooldays every semester; group 3 on three consecutive days once a month during semesters; group 4 once every fortnight during semesters, and group 5 (control) did not rinse. Radiographic recording of approximal caries was performed. FMR on the three first and the three last schooldays every semester (group 2) had a prevented fraction of 59%, with approximal enamel lesions as a diagnostic threshold. Corresponding figures for groups 1, 3 and 4 were 30, 47 and 41%, respectively. The control group differed statistically from groups 2-4 for new enamel and dentin lesions and fillings (p < 0.01). Enamel lesions constituted more than 90% of the new caries lesions. Caries progression was low for all groups and no significant differences were found between groups. The main conclusion from this randomised controlled trial is that school-based FMR, as a supplement to the daily use of F toothpaste, reduces caries incidence on approximal surfaces in adolescents with low to moderate caries risk.

Fluoride release from varnishes in two in vitro protocols

BACKGROUND

The authors conducted a study to evaluate fluoride released from fluoride varnishes that had been applied with two different protocols. Fluoride release information for these two approaches may allow clinicians to vary application intervals to better meet the needs of their patients.

METHODS

The authors painted enamel slabs from exfoliated primary molar teeth either in a single application (five samples) or three times within a single week (five samples) with fluoride varnish (Duraphat, Colgate-Palmolive, New York). The samples were immersed in buffered calcium phosphate solution (pH 6) to simulate the oral environment; the amount of fluoride released was measured during a span of six months.

RESULTS

The total release of fluoride was significantly higher in the three-application regimen (34.9 micromoles) than in the single application (23.7 micromol). The rate of release was slower using the three-application regimen. Thus, applying fluoride-release varnish three times in a single week produced greater and longer release of fluoride than did one application.

CLINICAL IMPLICATIONS

Massed application of fluoride varnish during a single period during the year may be as effective as spaced single applications. This method can be a good alternative to delivering fluoride varnish to high-caries-risk patients who are mobile or difficult to recall.

Caries-preventive effect of sodium fluoride mouthrinses: a systematic review of controlled clinical trials

The Swedish Council on Technology Assessment in Health Care launched a project group in 1999 to systematically review and evaluate the existing literature on different caries-preventive methods. The aim of this article was to report the findings concerning the caries-preventive effect of fluoride mouthrinses (FMRs) in various age groups, with special reference to background fluorides. A systematic search in electronic databases for literature published between 1966 and August 2003 was conducted with the inclusion criteria of a randomized or controlled clinical trial, at least 2 years' follow-up, and caries increment in the permanent dentition (DeltaDMFS/T) as endpoint. Out of 174 articles originally identified, 62 met the inclusion criteria. These studies were assessed independently by at least two reviewers and scored A-C according to predetermined criteria for methodology and performance. The measure of effect was the prevented fraction (PF) expressed as percent. The level of evidence was based on 25 articles. The results revealed limited evidence (evidence level 3) for the caries-preventive effect (PF 29%) of daily or weekly sodium fluoride rinses compared with placebo in permanent teeth of schoolchildren and adolescents with no additional fluoride exposure and for a caries-preventive effect on root caries in older adults. Inconclusive evidence (evidence level 4) was found regarding the effect of FMRs in schoolchildren and adolescents exposed to additional fluoride sources such as daily use of fluoride toothpaste. No firm support for the use of FMRs was disclosed in a small number of studies designed for patients at caries risk. Furthermore, no association between the frequency of the rinses and prevented fraction or saved surfaces per year was found. In conclusion, this systematic review suggests that sodium fluoride mouthrinses may have an anti-caries effect in children with limited background of fluoride exposure, while its additional effect in children with daily use of fluoride toothpaste could be questioned. The need for further clinical trials to elucidate the effect of FMRs in risk patients and older adults is emphasized.

Professional fluoride varnish treatment for caries control: a systematic review of clinical trials

The aim of this paper was systematically to evaluate the caries-preventive effect of professional fluoride varnish treatments. A search of the literature for articles published between 1966 and August 2003 was carried out in electronic databases, reference lists of articles, and selected textbooks in accordance with the strategy of the Swedish Council on Technology Assessment in Health Care. Out of 302 identified papers, 24 randomized and controlled clinical trials comparing fluoride varnish with placebo, no active treatment or other fluoride preventive regimens of at least 2 years' study duration were included. The trials that met the inclusion criteria were assessed independently and systematically by at least two reviewers and scored from A to C according to predetermined criteria for methodology and performance. The main outcome measure was the preventive fraction expressed as a percentage. The results displayed limited evidence (evidence level 3) for the caries preventive effect of topical applications of fluoride varnishes in permanent teeth. The average prevented fraction was 30% (0-69%) when compared with untreated controls. Inconclusive evidence (evidence level 4) was found for fluoride varnish treatment in the primary dentition and in adults. This systematic review reinforces the need for future dinical research of high quality, incorporating modern concepts of dinical performance and evaluation to assess dental caries control using professional fluoride varnish.

Combinations of topical fluoride (toothpastes, mouthrinses, gels, varnishes) versus single topical fluoride for preventing dental caries in children and adolescents

BACKGROUND

Topical fluoride therapy (TFT) in the form of toothpastes, mouthrinses, varnishes and gels are effective caries preventive measures. However, there is uncertainty about the relative value of these interventions when used together.

OBJECTIVES

To compare the effectiveness of two TFT modalities combined with one of them alone (mainly toothpaste) when used for the prevention of dental caries in children.

SEARCH STRATEGY

We searched the Cochrane Oral Health Group's Trials Register (May 2000), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2, 2000), MEDLINE (1966 to January 2000), plus several other databases. We handsearched journals, reference lists of articles and contacted selected authors and manufacturers.

SELECTION CRITERIA

Randomized or quasi-randomized controlled trials with blind outcome assessment, comparing fluoride varnish, gel, mouthrinse, or toothpaste in combination with each other in children up to 16 years during at least 1 year. The main outcome was caries increment measured by the change in decayed, missing and filled tooth surfaces (D(M)FS).

DATA COLLECTION AND ANALYSIS

Inclusion decisions, quality assessment and data extraction were duplicated in a random sample of one third of studies, and consensus achieved by discussion or a third party. Authors were contacted for missing data. The primary measure of effect was the prevented fraction (PF) that is the difference in mean caries increments between the 'treatment' and 'control' groups expressed as a percentage of the mean increment in the control group. Random effects meta-analyses were performed where data could be pooled.

MAIN RESULTS

Eleven of the 12 included studies contributed data for the meta-analyses. For the nine trials that provided data for the main meta-analysis on the effect of fluoride mouthrinses, gels or varnishes used in combination with toothpaste (involving 4026 children) the D(M)FS pooled PF was 10% (95% CI, 2% to 17%; p = 0.01) in favour of the combined regimens. Heterogeneity was not substantial in these results (I square = 32%). The separate meta-analyses of fluoride gel or mouthrinse combined with toothpaste versus toothpaste alone favour the combined regimens, but differences were not statistically significant; the significant difference in favour of the combined use of fluoride varnish and toothpaste accrues from a very small trial and appears likely to be a spurious result. Not all other combinations of possible practical value were tested in the included studies. The only other statistically significant result was in favour of the combined use of fluoride gel and mouthrinse in comparison to gel alone (pooled DMFS PF 23%; 95% CI, 4% to 43%; p = 0.02), based on two trials. No other combinations of TFT were consistently superior to a single TFT.

REVIEWER'S CONCLUSIONS

Topical fluorides (mouthrinses, gels, or varnishes) used in addition to fluoride toothpaste achieve a modest reduction in caries compared to toothpaste used alone. No conclusions about any adverse effects could be reached, because data were scarcely reported in the trials.

One topical fluoride (toothpastes, or mouthrinses, or gels, or varnishes) versus another for preventing dental caries in children and adolescents

BACKGROUND

Topical fluorides in the form of toothpaste, mouthrinse, varnish and gel are effective caries preventive measures. However, there is uncertainty about the relative value of these interventions.

OBJECTIVES

To compare the effectiveness of one form of topical fluoride intervention with another when used for the prevention of dental caries in children.

SEARCH STRATEGY

We searched the Cochrane Oral Health Group's Trials Register (May 2000), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2, 2000), MEDLINE (1966 to January 2000), plus several other databases. We handsearched journals, reference lists of articles and contacted selected authors and manufacturers.

SELECTION CRITERIA

Randomized or quasi-randomized controlled trials with blind outcome assessment, comparing fluoride varnish, gel, mouthrinse, or toothpaste with each other in children up to 16 years during at least 1 year. The main outcome was caries increment measured by the change in decayed, missing and filled tooth surfaces (D(M)FS).

DATA COLLECTION AND ANALYSIS

Inclusion decisions, quality assessment and data extraction were duplicated in a random sample of one third of studies, and consensus achieved by discussion or a third party. Authors were contacted for missing data. The primary measure of effect was the prevented fraction (PF) that is the difference in mean caries increments between the 'experimental' and 'control' groups expressed as a percentage of the mean increment in the control group. Random effects meta-analyses were performed where data could be pooled.

MAIN RESULTS

There were 17 studies included, and 15 contributed data for the meta-analyses. Fluoride toothpaste was not significantly different from mouthrinse (pooled DMFS PF 0%; 95% CI, -18% to 19%; p = 0.94), or gel (pooled DMFS PF 0%; 95% CI, -21% to 21%; p = 1), or both gel and mouthrinse (pooled DMFS PF 1%; 95% CI, -13% to 14%; p = 0.94); heterogeneity was substantial. Results from the single trial comparing toothpaste with varnish (in deciduous teeth) were inconclusive (dfs PF 5%; CI not obtainable). The pooled results from the comparisons of fluoride varnish with mouthrinse was a non-significant difference favouring varnish (DMFS PF 10%; 95% CI, -12% to 32%; p = 0.40), but this result was not robust to sensitivity analysis performed, and heterogeneity was considerable. Results from the single trial comparing varnish with gel (14%, 95% CI, -12% to 40%; p = 0.30) and the single trial comparing gel with mouthrinse (-14% DMFS PF; 95% CI, -40% to 12%; p = 0.30) were inconclusive (favoured varnish and mouthrinse respectively).

REVIEWER'S CONCLUSIONS

Fluoride toothpastes in comparison to mouthrinses or gels appear to have a similar degree of effectiveness for the prevention of dental caries in children. There is no clear suggestion that fluoride varnish is more effective than mouthrinses and the evidence for the comparative effectiveness of fluoride varnishes and gels, and mouthrinses and gels is inconclusive. No conclusions about adverse effects could be reached, because no data were reported on in the trials. Acceptance is likely to be greater for fluoride toothpaste.

Fluoride varnish for caries prevention: comparisons with other preventive agents and recommendations for a community-based protocol

This paper reviews fluoride varnish (FV) literature to develop a community-based protocol for people with special needs or those who are caries susceptible. Safety, personnel and cost issues are discussed and existing NIH, CDC and WHO recommendations are presented. FV studies are assessed with respect to type of FV to use and frequency of application. FV is compared with studies using other caries preventive agents: 0.2% NaF mouthrinse, acidulated phosphate fluoride (APF) gel, dental sealants, water fluoridation and chlorhexidine. Because there are few FV studies among special need populations, conclusions are based on available literature and public health principles. If personnel are available, FV use is preferred to APF gel and may be preferable to 0.2% NaF mouthrinse. FV is more effective in optimally fluoridated communities. If many occlusal surfaces are at risk, sealants should be applied. Additional combinations and frequencies of preventive agents should be tested, especially for people with special needs and high caries risk adults.

Caries reductions related to the use of fluorides: a retrospective cohort study

AIM

To test whether topical fluoride regimes provided additional caries protection to the first molar teeth of children exposed to fluoridated toothpaste and optimally fluoridated water supplies.

PARTICIPANTS AND METHODS

This two-year retrospective cohort study included 660, 8-year-old-children. A cluster sampling technique was used to select three groups of 220 children. Group 1 was selected from schools using fluoride mouthrinses (Programme 1). Group 2 was selected from schools applying fluoride gel (APF 1.23%) in addition to the weekly fluoride mouthrinse (Programme 2). Oral health education and oral hygiene instruction were provided to both groups. The control group was selected from schools in the same area that had not adopted any oral health preventive programme. All children were exposed to optimally fluoridated water and fluoridated toothpaste for the last two years or more. Participants were examined for DMFS scores of their first molars using WHO criteria by one examiner (MLRS).

RESULTS

The percentage caries free children in Control, Programme 1 and Programme 2 were 55%, 65% and 65.5%, respectively. The differences between Programme 1 and 2 in relation to the Control Group were statistically significant (P < 0.05). There was no difference between Programme 1 and 2 (P = 0.92).

CONCLUSIONS

Weekly fluoride rinsing combined whether or not with fluoride gel applications once every three months, provided additional caries-preventive benefits to children with high levels of caries and exposed to optimally fluoridated drinking water and toothpaste. There was no difference in caries levels between children having fluoride rinses and those having fluoride rinses and fluoride gel.

Caries incidence in adolescents with low caries prevalence after cessation of weekly fluoride rinsing

The aim of this study was to determine whether cessation of weekly fluoride rinsing leads to an increase in caries incidence in a group of adolescents with low caries prevalence. Sixty randomly selected 12- to 14-year-olds were asked to stop rinsing at school (test group). After 3 years caries increment and caries progression were compared with an age- and sex-matched control group (n = 60), who continued to rinse weekly with a 0.2% sodium fluoride solution. All children in both groups had followed a school-based fluoride rinsing program from the age of 6 years. The mean (standard deviation) caries increment, including only open lesions, during the 3 years was 1.58 (1.73) in the test group and 1.48 (1.80) in the control group. The corresponding figures for incipient lesions were 3.13 (3.63) and 4.03 (4.23), respectively. The mean caries progression was 0.92 (1.34) in the test group and 0.72 (1.03) in the control group. None of these differences were statistically significant. Thus, this study showed that a cessation of weekly fluoride rinsing did not lead to an increase of caries incidence in a group of adolescents with low caries prevalence.

Oral health in the United States: the post-fluoride generation

Tremendous strides have been made in reducing the incidence of tooth decay, periodontal diseases, and associated loss of teeth in adults and children since the inception of community water fluoridation programs. Yet the disadvantaged and poor have not fully shared in the benefits. Other challenges to oral health remain. Oral cancer and related smoking and smokeless tobacco use remain major public health problems. Access to preventive and therapeutic dental care is far from universal. Public health programs similar in commitment to the approach of community water fluoridation programs initiated in the 1950s and 1960s are needed to address neglected oral health needs of underserved and high-risk populations in the United States.

Fluoride varnishes. A review of their clinical use, cariostatic mechanism, efficacy and safety

BACKGROUND

This is a review of the clinical use, cariostatic mechanism, efficacy, safety and toxicity of fluoride varnishes.

TYPES OF STUDIES REVIEWED

The authors reviewed and summarized in vitro, in vivo and in situ studies; clinical trials; demonstration programs; position papers; and editorials published in English in the biomedical literature since 1966.

RESULTS

Extensive laboratory research and clinical trials conducted in Europe and elsewhere show that fluoride varnishes are as efficacious as other caries-preventive agents. Fluoride varnishes are widely used in European caries-preventive programs. The U.S. Food and Drug Administration has cleared these products only as medical devices to be used as cavity liners and for the treatment of hypersensitive teeth. These products have not yet been cleared for marketing in the United States as caries-preventive agents.

CLINICAL IMPLICATIONS

Three fluoride varnishes are currently available in the United States. Semiannual applications are the most proven treatment regimen. Varnishes are safe and easy to apply and set in contact with intraoral moisture.

Caries development after substitution of supervised fluoride rinses and toothbrushings by unsupervised use of fluoride toothpaste

In a nonfluoridated community of Finland, where fortnightly fluoride rinsing with 0.2% sodium fluoride has been used for nearly two decades, a total of 313 children 7-8 yr old were recruited and randomly divided into two groups. 206 children completed the 3-yr trial. The control group (n = 94) participated in the rinsing program which included supervised toothbrushings, while the test group (n = 112) received a new fluoride toothpaste tube (0.15% F) for home use every second month. Annual dental recordings, treatment plannings and the treatment itself were all carried out by one clinician. At the end of the study the number of caries-free children of the toothpaste group was lower (P < 0.01) and the caries increment higher (P < 0.05) than that of the mouthrinse group. Out of the mean of four dental visits per child and year some 1.5 were prophylactic by nature. No differences were found between the number of treatment visits, time or prophylactic care of the two groups. Unsupervised use of fluoride toothpaste may not be a sufficient substitute for the school-based fortnightly fluoride rinses and supervised toothbrushings in caries prevention of children with erupting permanent teeth.

Professional topical fluoride applications--clinical efficacy and mechanism of action

All currently used topical fluoride agents deposit soluble fluoride as calcium fluoride on enamel or in lesions. Calcium fluoride serves as a source of fluoride for the formation of fluorapatite. The latter phase is formed when pH drops in plaque, not during topical application. The potential for calcium fluoride formation should probably be increased in topical fluoride agents. In countries with low caries prevalence, the clinical recommendations for topical fluoride need to be reconsidered. Toothpaste is the basic fluoride regimen recommended for everybody. The need for additional fluoride supplementation depends on caries activity. There is no distinct difference in the caries-preventive effects of concentrated fluoride solutions, gels, or varnishes. Thus, the choice of method depends on costs, convenience, patient acceptance, and safety. The use of fluoride varnishes has proven to be a feasible and safe method of fluoride application. With fluoride varnishes, the amounts of fluoride exposure can be better controlled, and less chair-time is required compared with conventional solutions and gels. No dose-response effect to concentrated fluoride agents is apparent, and the benefit of frequent application is not clearly established. In individuals with the most severe cariogenic challenge, combinations of fluoride and antimicrobials may give better clinical effects than fluoride alone.

Four-year study of caries inhibition of intensive Duraphat application in 11-15-year-old children

The purpose of the study was to evaluate the caries preventive effect and cost of an intensive application of Duraphat varnish, added to the regular preventive program for 11-15-yr-old children in a Swedish Dental Community Clinic. In 1987, the 134 11-yr-old children in Floda were divided into two groups, every second child to each. Children with fixed orthodontic appliances were excluded. The test group received three applications of Duraphat varnish during 1 week, once a year, by a dental nurse. The control group received one application at the annual check-up. Both groups were included in the regular preventive program at the clinic. The total time cost for the clinic was estimated and used to calculate the cost per hour for dentists and nurses. The caries increment and progression were estimated both by routine diagnosis and by a careful study of radiographs taken at the beginning and end of the study period. There was a small caries increment and progression in the test group as compared to the control group. The difference was statistically significant for all aspects studied. The costs were about the same in both groups but more time was used in the test group. The administrative effort for the staff was considerable for the intensive Duraphat application.

Preventing dental caries: breaking the chain of transmission

Besides using all possible techniques to increase host resistance (fluoride, sealants) and decrease exposure to fermentable carbohydrates (for example, use of sugar substitutes), dentists must treat caries as infectious and transmissible. Antimicrobial agents are recommended.

Combined fluoride therapies. A 6-year double-blind school-based preventive dentistry study in Inverness, Scotland

A 6-yr double-blind study was undertaken to compare the caries inhibiting-effectiveness of (a) 1 mgF- tablets (daily at school) plus fortnightly rinsing at school with 1000 ppmF-; (b) 1 mgF- tablets plus placebo rinsing; and (c) placebo tablets plus 1000 ppmF- rinsing. Participants were aged 4.5-5 yr at outset of the trial. At baseline, and annually thereafter, clinical caries and bitewing X-ray examinations were undertaken, hence ethical approval for a negative control was not feasible. Fissure sealant presence was also recorded. Initially, 192 children from predominantly low socio-economic backgrounds were enrolled, and baseline analyses showed no significant differences between groups with respect to primary caries prevalence. After 6 yr, 112 children remained, by which time no significant differences were noted between DMFT and DMFS values for those in the active tablet/active rinse group, as compared to those in the placebo tablet/active rinse group. However, in relation to both indices, in permanent first molars, the effectiveness of the active tablet/placebo rinse regime appeared to be significantly poorer than the placebo tablet/active rinse programme. For the active tablet/active rinse group, the DMFT difference was significantly less than the active tablet/placebo rinse group (37.9%), although for the DMFS difference, significance was not achieved. Similar trends were noted when DMFT and DMFS values for all permanent teeth were considered. The occlusal caries prevalence in permanent first molars followed the DMFT pattern, but differences between combined tablet/rinsing children and tablet-only children could be ascribed solely to the effectiveness of sealant presence.(ABSTRACT TRUNCATED AT 250 WORDS)

An evaluation of the use of professional (operator-applied) topical fluorides

Application of fluoride solutions, gels, varnishes, and prophylaxis pastes is reviewed as well as the sequential APF/SnF2 office-rinse method. The most widely-used technique is with 1.23% APF gel (12,300 ppm F) in trays. Clinical results from this method are similar to those achieved with an APF solution of the same fluoride concentration. A professional APF gel/tray application need not be preceded by a prophylaxis, should last four min, and should not be followed by a water rinse for 30 min. Fluoride varnishes are newer topical fluoride agents, but their relative efficacy, compared with other proven caries-inhibitory methods, remains to be fully determined. In general, fluoride prophylaxis pastes have not been shown to inhibit caries; however, their use is justified by the ability of some to replenish fluoride lost from the abrasive action of the paste on tooth enamel. The sequential office-rinse method has not been tested in randomized clinical trials, and its use cannot be recommended.

Effectiveness of mouthrinsing with fluoride solutions in preventing coronal and root caries

Fluoride mouthrinses have been used extensively for the past 15 years to prevent dental caries in children. Their use has been especially widespread in organized school-based programs in the US. Nearly three dozen clinical studies of fluoride mouthrinses, both with and without placebo controls, have been reported in the literature since the early 1960s. The overwhelming majority of those studies report statistically significant caries inhibition from the use of the products. Most of the studies were published prior to the knowledge of a decline in caries prevalence during the past 30 years. Consequently, the results of those studies lacking a placebo control group have been challenged. Even randomized clinical trials with appropriate control groups appear to be reporting declining differences between test and control groups. Using a model based on annual caries increments from published studies, the conclusion is reached that future use of fluoride mouthrinses is unlikely to result in annual savings in DMF increment greater than 0.4 surfaces, regardless of age of rinsers.

Comparative effects of a 4-year fluoride mouthrinse program on high and low caries forming grade 1 children

This paper presents the comparative effectiveness of fluoride mouthrinse (FMR) on high and low caries forming children after a 4-yr exposure to weekly rinse beginning in the first grade. Over 1200 grade 1 children drawn from both fluoride deficient and fluoridated sites were divided into treatment and concurrent, longitudinal control groups. After 4 yr these children were stratified according to caries increment; those above the 75th percentile were considered high caries formers, all others were designated low caries formers. After adjustment of the mean increments for differences in SES, age, race, and sex in rinse and control groups, high caries formers (approximately 25% of the children) in the rinse and control groups in fluoride deficient areas showed increments of 7.00 and 7.79 surfaces, respectively, indicating a savings of 0.79 surfaces. Low caries formers (approximately 75% of the children) demonstrated increments of 1.11 DMFS in the rinse group and 1.40 in the control group (savings 0.29 DMFS). The pattern was quite similar for children in fluoridated areas except that the increments, as well as the savings realized, were lower. The results raise questions as to the practical effectiveness of school based FMR programs even for high caries forming children.

Effect on approximal caries in teenagers of interrupting a school-based weekly NaF mouthrinse program for 3 years

The aim of the present investigation was to follow the caries incidence in 126 13-yr-old children who experienced a 3-yr interruption of a supervised weekly mouthrinse program with 0.2% NaF solution (interrupted rinsing-, IR-group). 143 children, 13 yr old, who continuously participated in the NaF mouthrinse program, served as a comparison group (continuous rinsing-, CR-group). Dental caries and restorations were diagnosed on bitewing radiographs; thus only approximal tooth surfaces were considered. The caries incidence over the 3-yr period was 1.84 DFS in the IR- and 1.77 in the CR-group. The corresponding FS-values were 0.67 and 0.25, respectively. Two years later, i.e. when the children were 18-yr-old and the IR-group had had 2 yr back on the school-based mouthrinse program, they were examined again. The difference in caries incidence between 16 and 18 yr of age was still small, 1.32 DFS in the IR- and 1.22 in the CR-group. The corresponding FS-values were 0.63 and 0.49, respectively. Thus, this study showed that the 3-yr interruption of the NaF mouthrinse program resulted in a small, statistically non-significant increase in caries, mostly as regards the number of fillings, on approximal tooth surfaces.