Need for prior toothcleaning when performing a professional topical fluoride application: review and recommendations for change

Efficacy of fluoride gel in arresting active non-cavitated caries lesions: a randomized clinical trial

This study evaluated the efficacy of fluoride gel in arresting active non-cavitated caries lesions in permanent teeth. This randomized, triple-blind, placebo-controlled clinical trial randomized 100 schoolchildren aged 10.7 ± 2.2 years to test treatment (1.23% acidulated phosphate fluoride [APF] gel) or control treatment (placebo gel) for 4-6 applications at weekly intervals. Data collection included the visible plaque index, gingival bleeding index, visible plaque accumulation on the occlusal surfaces, eruption stage, and dental caries. The association between group and lesion arrestment was assessed using logistic regression, and estimates were adjusted for plaque accumulation over the lesion at baseline, surface type, and tooth type. Models were fitted using generalized estimating equations for accounting for the clustering of data (i.e., the same individual contributed > 1 lesion). Ninety-eight children completed the study (48 fluoride and 50 placebo). When all dental surfaces were analyzed, the likelihood of lesion arrestment was similar between both groups (p > 0.05). A secondary analysis including only the occlusal lesions in molars showed that for teeth under eruption, lesions receiving the 1.23% APF gel were about 3-fold more likely to become arrested than lesions receiving the placebo gel (OR = 2.85; 95%CI = 1.23-6.61; p = 0.01). No significant difference was detected for molars with complete eruption (p > 0.05). The benefit of fluoride gel for arresting non-cavitated caries lesions could not be identified by clinical assessment in this short-term trial. Notwithstanding, when the cariogenic challenge was greater (as on the occlusal surfaces of erupting molars), 1.23% APF gel treatment was an important tool for caries control.

Concentration-Dependent Multi-Potentiality of L-Arginine: Antimicrobial Effect, Hydroxyapatite Stability, and MMPs Inhibition

This study's objective was to examine L-arginine (L-arg) supplementation's effect on mono-species biofilm (Streptococcus mutans/Streptococcus sanguinis) growth and underlying enamel substrates. The experimental groups were 1%, 2%, and 4% arg, and 0.9% NaCl was used as the vehicle control. Sterilised enamel blocks were subjected to 7-day treatment with test solutions and S. mutans/S. sanguinis inoculum in BHI. Post-treatment, the treated biofilms stained for live/dead bacterial cells were analysed using confocal microscopy. The enamel specimens were analysed using X-ray diffraction crystallography (XRD), Raman spectroscopy (RS), and transmission electron microscopy (TEM). The molecular interactions between arg and MMP-2/MMP-9 were determined by computational molecular docking and MMP assays. With increasing arg concentrations, bacterial survival significantly decreased (p < 0.05). The XRD peak intensity with 1%/2% arg was significantly higher than with 4% arg and the control (p < 0.05). The bands associated with the mineral phase by RS were significantly accentuated in the 1%/2% arg specimens compared to in other groups (p < 0.05). The TEM analysis revealed that 4% arg exhibited an ill-defined shape of enamel crystals. Docking of arg molecules to MMPs appears feasible, with arg inhibiting MMP-2/MMP-9 (p < 0.05). L-arginine supplementation has an antimicrobial effect on mono-species biofilm. L-arginine treatment at lower (1%/2%) concentrations exhibits enamel hydroxyapatite stability, while the molecule has the potential to inhibit MMP-2/MMP-9.

The Effect of Saliva on the Formation of KOH-Soluble Fluoride after Topical Application of Amine Fluoride Solutions of Varying Fluoride Concentration and pH

The effect of saliva on the amount of KOH-soluble fluoride formed on a sound enamel surface after application of amine fluoride solution of varying fluoride concentrations (1, 0.5 and 0.25% F) and pH (5.3, 4.5 and 4.0) was examined in an in vitro study. The saliva pretreatment increased the amount of KOH-soluble fluoride at the highest pH value. For any given fluoride concentration, the presence of saliva did not influence the amount of KOH-soluble fluoride. These data suggest that saliva could enhance the amount of KOH-soluble fluoride if the topical fluoride preparations are not highly acid.

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.

Current status of professionally applied topical fluorides

The literature was reviewed to establish the current effectiveness of professionally applied topical fluorides in the prevention of dental caries and to determine the risk of chronic and acute fluoride ingestion from their use. Use of professionally applied topical fluorides by moderate to high risk children and adults is supported by existing research. Although many of the studies are dated, there is sufficient evidence to support their continued use. Professionally applied topical fluorides are not a risk factor for dental fluorosis, though they have been implicated in acute reactions. The precautions needed to minimize fluoride intake are discussed.

Caries prevention--fluoride

A clear understanding of the mechanism of action of fluoride and its pharmacokinetics would ensure appropriate clinical use of fluoride and fluoride-containing modalities. Convincing evidence exists that fluoride has a major effect on the demineralization and remineralization of dental hard tissues, and that it interferes with the acid production from "cariogenic" bacteria. However, it has also been shown to be physiologically harmful if fluoride concentrations and/or exposure periods are inappropriate. In order to establish appropriate clinical concentrations and exposure periods for fluoride administration, this review is concentrated on the theme that fluoride controls but does not prevent caries. The review is organized along classical lines, with a discussion of the role of systemic vs. topical fluoride. Discussion of the systemic effects of fluoride includes ingestion through water fluoridation, fluoride supplements, topical fluoride applications, and dentifrices. The benefits and problems associated with the systemic route of fluoride administration are discussed with special reference to caries control and fluoride's mechanism of action and its toxic effect. The same discussions are focused on the role of the topical effects of fluoride, with particular emphasis placed upon: low vs. high fluoride concentrations; calcium fluoride vs. fluorhydroxyapatite; and fluoride distribution, in both the mouth and in the teeth.

A critique of topical fluoride methods (dentifrices, mouthrinses, operator-, and self-applied gels) in an era of decreased caries and increased fluorosis prevalence

Within the last 20 years there has been a decrease in the caries prevalence of US schoolchildren, a change in the intraoral caries pattern, and a slowing of the progress of lesions. Simultaneously, the prevalence of enamel milder, cosmetically acceptable forms and is more noticeable in fluoride-deficient communities than those with optimal or above-optimal water fluoride concentrations. Circumstantial evidence indicates that a principal contributor to the caries decline is the extensive use of fluoride dentifrices. Conversely, although use of a fluoride dentifrice can add to the total daily amount of ingested fluoride in preschool children, there is little evidence to suggest that dentifrice ingestion is a principal factor causing the fluorosis increase. The value of fluoride methods may be assessed in relative or absolute terms. The relative, or percentage, caries reduction attributed to fluoride mouthrinses and gels appears to be a property intrinsic to the methods themselves and generally is little affected by the caries activity of the population being treated. Conversely, the absolute, or numerical, caries reduction is dependent upon the level of disease in the population. Thus, the reported caries decline reduces the number of surfaces prevented from developing caries, even though the percentage reduction remains substantially unchanged. Although inadvertent ingestion of fluoride can result from the use of mouthrinses and gels, there is little evidence to suggest that they have contributed to the fluorosis increase. When using topical methods, prudence should prevail to avoid ingestion of fluoride. Fluoride dentifrices should continue to be used routinely, and although lower potency dentifrices may be considered, the literature does not provide strong support for their need. Use of fluoride mouthrinses and gels for individual patients should be predicted upon their caries activity or risk. Use of these methods in public health programs is a matter of cost-effectiveness, which will be influenced by the caries prevalence of the target population.

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.

Fluoride in dental plaque and its effects

Total plaque fluoride is in the range 5-10 mg/kg (ppm) on a wet-weight basis. The variability of literature data on plaque fluoride is partly ascribed to analytical problems, many assays being close to or below the concentration detection limit of the fluoride electrode. A change in classification of plaque fluoride compartments is necessary, since recent work indicates that there are two pools of plaque F: less than 5% of the total F is in plaque fluid as the free ion, and the large remaining portion of total plaque F is designated as bound F, with the total F being greater than 95% extractable by cold 0.5 mol/L perchloric acid. Sources of plaque fluoride include the diet, saliva, and crevicular fluid; enamel is unlikely to be a regular source for plaque F unless it is either coated daily with labile fluoride compounds, such as calcium fluoride, or released by demineralization. The location and nature of plaque bound F are not established, but the present evidence is consistent with an intracellular location. Bound F may be released by acids produced in plaque during sugar fermentation, but it is unlikely to reach ion concentrations high enough for sufficient time periods to exert significant inhibition of plaque acidogenesis. Epidemiological evidence showing correlations between pooled plaque F concentrations and caries prevalence in the plaque donors does not exclude the possibility of coincidental effects of water F on both caries and plaque F concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of topical fluoride preparations

For practical reasons, evaluation of topical fluoride products must depend upon clinical and laboratory assessments. While not always a good predictor of clinical efficacy by itself, fluoride uptake is the most commonly used laboratory test. A consideration of the relationship between possible anticaries mechanisms of fluoride, different product types, and the meaning of various kinds of fluoride uptake data suggests that both the amount of fluoride taken up by early lesions and the amount of ambient fluoride present at a cariogenic site may play key roles in determining the efficacy of a product. While formulations applied annually or semi-annually probably depend on fluoride deposition, those used daily might not. There are no clear data supporting the superiority of one fluoride compound over another, even for infrequently used products, although there are significant differences among them in fluoride uptake by enamel. This suggests that fluoride uptake in vivo at a cariogenic site might actually be different from that suggested by in vitro data, or that larger differences are required for a clinical effect to be observable. Clinical data support the conclusion that a large increase in the fluoride concentration of a product will somewhat increase its anticaries effectiveness, although the increase will not be linearly related to concentration. There also are no obvious differences in clinical effectiveness caused by the addition of gelling agents to topical solutions. Fluoride varnishes are clinically effective but have not been shown to be superior to topical solutions or gels.(ABSTRACT TRUNCATED AT 250 WORDS)

Review of the anticaries effectiveness of professionally applied and self-applied topical fluoride gels

Of the five types of topical fluoride gel products available in the United States, two have not been clinically tested in randomized double blind clinical trials. For those tested, the averaged results of clinical trials involving schoolchildren in fluoride-deficient communities indicate a caries reduction of approximately 26 percent from either a professional or self-administered program. A similar relative reduction can be expected from programs conducted in fluoridated communities, but the absolute caries inhibition is less. Twice-a-year professional applications are more effective than once-a-year applications, and self-applications using trays are more effective than applying the gel on a toothbrush. For subjects beyond school age, there are few clinical studies of either self-applied or professionally applied gels; however, current epidemiological evidence does not indicate a need for public health caries preventive programs for healthy employed adults. For medically compromised patients, especially those exhibiting rampant caries associated with radiation-induced xerostomia, a variety of topical gel procedures appear to be effective in limiting caries.

Oral assessment of the dentulous elderly patient

The percentage of elderly persons retaining natural teeth is increasing. Although many of these individuals cannot be convinced to see a dentist regularly, they are generally seen by a physician or nurse relatively frequently. The physician or nurse can provide a vital service for these patients by performing oral screening examinations. A technique is described for accomplishing this.