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Objectives: To compare the fluoridating potential of selected European toothpastes using a combination of enamel, dentin, and plaque in vitromodels., Methods: Four in vitromodels were included: 1) Enamel Fluoride (F) Uptake (EFU); 2) Dentin F Uptake (DFU); 3) Enamel Solubility Reduction (ESR); and 4) Plaque F Uptake (PFU). A core set of marketed products was included in all studies, plus a standard toothpaste (1100 ppm F as NaF/silica) and placebo control (the PFU study did not include a placebo control). Test dentifrices: [A] Fluocaril® Bi-Fluoré 250 (1500 ppm F as NaF+1000 ppm F as SMFP); [B] LacerAnticaries (2500 ppm F as SMFP); [C] Elmex® Caries Professional™ (1450 ppm F as SMFP+1.5% arginine); [D] Colgate® Triple Action (1450 ppm F as SMFP); [E] Placebo (0 ppm F); and [F] standard toothpaste (1100 ppm as NaF/silica). In all studies (EFU, DFU, ESR, and PFU), assessments were compared for each pair using the Tukey-Kramer HSD test (p < 0.05)., Results: In all studies of fluoride uptake, the Fluocaril dentifrice [A] provided the greatest numerical benefit, regardless of the substrate. Statistical groupings were EFU: A > F = B = C = D > E; DFU: A > F = B = C = D = E; PFU: A = B > F = C = D). In demineralization prevention, the Fluocaril dentifrice [A] also provided the greatest benefit (ESR: A = F = C = B = D > E). In all studies that included a placebo control, all of the F-containing dentifrices performed better than the placebo control., Conclusions: While these results demonstrate that all of the marketed products tested provide effective anticaries benefits, the Fluocaril Bi-Fluoré 250 dentifrice consistently delivered unsurpassed performance. It delivered the highest level of F to plaque, provided greater measures of efficacy in both remineralization and inhibition of demineralization, and delivered substantial improvement in fluoridation of dentin, suggesting the potential for delivering both coronal and root caries benefits., Competing Interests: All authors are employees of Procter & Gamble.

Objectives: There is some evidence that water rinsing immediately after topical fluoride therapy has the potential to reduce the effectiveness of fluoride. The aim was to determine if covering fluoridated teeth with a layer of mousse containing CPP-ACP could prevent the adverse effect of rinsing on fluoride and consequently its buffering effect on dental plaque pH during cariogenic challenge., Study Design: This randomized, controlled, crossover, in situ study was conducted on 25 participants. The participants were subjected to acidulated phosphate fluoride (APF) application followed by five treatment protocols: (1) water rinsing after 30 minutes (APF-30) or (2) immediate water rinsing (APF-0); (3) using CPP-ACP immediately before water rinsing (F-CPP-ACP); and two control groups: (4) no fluoride therapy (No-F) and (5) using CPP-ACP and immediate water rinsing (CPP-ACP-0). After 48 hours, teeth were rinsed with 10% sucrose solution and plaque pH was measured before and after 5, 10, 15, 20 and 30 minutes., Results: The least pH changes, the lowest pH drop, and the quickest pH recovery were found in the APF-30 and F-CPP-ACP groups. APF-0 ranked in the middle and the highest values were in the control groups., Conclusions: The results show that in the case using CPP-ACP on fluoridated teeth, water rinsing immediately after topical fluoride therapy did not seem to influence the inhibitory effect of fluoride on plaque acidity.

Objective: To determine the effect of the mode of drinking fluoridated milk on salivary and plaque fluoride concentrations., Methods: Fluoridated milk was ingested by 32 children in three ways: (a) directly from the container (1.0 and 5.0 mg F/litre), (b) through a straw with the tip between the lips (5.0 mg F/litre), and (c) with the tip deep in the oral cavity (5.0 mg F/litre). Saliva was collected at baseline and 2, 15, and 40 min and plaque at baseline and 20 min after drinking. Fluoride concentrations were determined using the electrode after HMDS-facilitated diffusion., Results: The mode of drinking did not affect fluoride concentrations in saliva or plaque. The average 2-min salivary concentrations were 65 ng F/mL for the 1.0 mg F/litre group and 276 ng F/mL for the three 5.0 mg F/litre groups (P < 0.01). The average of the 15- and 40-min salivary concentrations was 22 ng F/mL for the 1.0 mg F/litre group and 41 ng F/mL for the 5.0 mg F/litre groups (P < 0.01). Plaque concentrations showed the same patterns as in saliva, that is, they were higher in the three 5.0 mg F/litre groups than in the 1.0 mg F/litre group and the differences among the 5.0 mg F/litre groups were not statistically significant., Conclusion: Salivary and plaque fluoride concentrations were independent of the mode of drinking but directly related to milk fluoride concentrations., (© 2015 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To assess the efficacy of an experimental 1450 ppm fluoride as sodium monofluorophosphate (SMFP)/zinc-based dentifrice (Test), a clinically proven 1450 ppm fluoride as SMFP/zinc-based dentifrice (Positive Control), and a 1000 ppm fluoride as SMFP and 450 ppm fluoride as sodium fluoride (NaF) dentifrice (Negative Control) in delivering 12-hour anti-tartar benefits as measured by calcium buildup after a single product brushing., Methods: Fourteen (14) adult subjects completed this single-center, double-blind, randomized, cross-over clinical study conducted in Piscataway, New Jersey. An intra-oral appliance was custom-made for each subject as a surface on which the anti-calculus agents' inhibition of early calculus formation could be analyzed. After brushing with their assigned toothpaste, each subject wore their respective appliance for 12 hours overnight. When the appliance was removed, it was washed, suspended in 0.1 MHCL to release Ca2+ from deposits, and analyzed by Inductively Coupled Plasma (ICP) for deposited calcium. There was a one-week washout period between each product use. Statistical analyses were performed on the mean level of calcium (μg). Comparisons of the treatment groups with respect to 12-hour post-brushing (overnight) calcium levels were performed via a two-way analysis of variance (ANOVA), with subjects and products as factors in the ANOVA model. Post-ANOVA pair-wise comparisons of the study treatments were performed using the Tukey's test for multiple comparisons. All statistical tests of hypothesis were two-sided, and employed a level of significance of α = 0.05., Results: At the 12-hour post-brushing examination, the mean level of calcium buildup was 0.46 μg for subjects assigned to the experimental Test dentifrice, 0.41 μg for subjects assigned to the Positive Control dentifrice, and 2.47 μg for subjects assigned to the Negative Control dentifrice. After 12 hours post-brushing, subjects assigned to the experimental Test dentifrice and Positive Control dentifrice both exhibited statistically significantly (p = 0.005 and p = 0.004, respectively) lower levels of calcium buildup as compared to the subjects assigned to the Negative Control dentifrice. No statistically significant (p = 0.996) difference was observed between the experimental Test dentifrice and Positive Control dentifrice with respect to tartar control efficacy after 12 hours post-brushing. No adverse effects of the hard or soft oral tissue were observed by the clinical investigators or reported by the subjects., Conclusion: Both the experimental Test dentifrice (1450 ppm fluoride as SMFP/zinc-based dentifrice) and the Positive Control dentifrice (1450 ppm fluoride as SMFP/zinc-based dentifrice) provided significantly greater 12-hour tartar control as measured by calcium buildup, as compared to the Negative Control dentifrice containing 1000 ppm fluoride as SMFP and 450 ppm fluoride as NaF.

Increasing the concentration of free fluoride in oral fluids is an important goal in the use of topical fluoride agents. Although sodium lauryl sulfate (SLS) is a common dentifrice ingredient, the influence of this ion on plaque fluid and salivary fluid fluoride has not been examined. The purpose of this study was to investigate the effect of SLS on these parameters and to examine the effect of this ion on total (or whole) plaque fluoride, an important source of plaque fluid fluoride after a sufficient interval following fluoride administration, and on total salivary fluoride, a parameter often used as a surrogate measure of salivary fluid fluoride. Ten subjects accumulated plaque for 48 h before rinsing with a 12 mmol/l NaF (228 µg/g F) rinse containing or not containing 0.5% (w/w) SLS. SLS had no statistically significant effect on total plaque and total saliva fluoride but significantly increased salivary fluid and plaque fluid fluoride (by 147 and 205%, respectively). These results suggest that the nonfluoride components of topical agents can be manipulated to improve the fluoride release characteristics from oral fluoride reservoirs and that statistically significant change may be observed in plaque fluid and salivary fluid fluoride concentrations that may not be observed in total plaque and total saliva fluoride concentrations.

This single-blind, randomized, crossover study aimed at assessing the long-term fluoride concentrations in saliva and in dental biofilm after different home-use fluoride treatments. The study volunteers (n = 38) were residents of an area with fluoridated drinking water. They were administered four treatments, each of which lasted for one week: twice-daily placebo dentifrice, twice-daily fluoride dentifrice, twice-daily fluoride dentifrice and once-daily fluoride mouthrinse, and thrice-daily fluoride dentifrice. At the end of each treatment period, samples of unstimulated saliva and dental biofilm were collected 8 h after the last oral hygiene procedure. Fluoride concentrations in saliva and dental biofilm were analyzed using a specific electrode. The fluoride concentrations in saliva and dental biofilm 8 h after the last use of fluoride products did not differ among treatments. The results of this study suggest that treatments with home-use fluoride products have no long-term effect on fluoride concentrations in saliva and in dental biofilm of residents of an area with a fluoridated water supply.

The purpose of this study is to determine whether a calcium (Ca) prerinse used before a 228 µg/g (ppm) fluoride (F) rinse would induce the formation of 'calcium fluoride-like' (CaF2-like) deposits in human dental plaque. Sixty minutes after the use of the Ca prerinse/F rinse, plaque samples were collected from 10 volunteers, homogenized, and split into 2 aliquots. The plaque mass from one aliquot was then extracted with a 'plaque-like' solution that extracted all the CaF2-like deposits. The total F in both aliquots was then determined and compared. The results demonstrated that, as in previous studies, the Ca prerinse induced large increases in plaque fluid and total plaque F. However, unlike previous results without the Ca prerinse, 30% of the plaque F deposits were CaF2 or CaF2-like. Given that maintaining an elevated F concentration in the vicinity of a developing lesion may play an important role in the cariostatic effect of this ion, and the potential advantages of CaF2-like deposits as an F source, these results suggest that a Ca prerinse may increase the cariostatic effect of topical agents.

Aim: The effects on plaque parameters of sugar free chewing-gums (CG) sweetened with either maltitol or xylitol were assessed to better understand the role polyols can play in dental caries prevention., Materials and Methods: A double-blind, parallel, randomised, controlled study was conducted in China. Subjects (N = 258, age = 13 to 15 years-old) were divided into 4 groups: 2 receiving polyols CG, containing respectively maltitol or xylitol, a group receiving gum base (placebo) and a negative control group not receiving any gum. CG were chewed for 30 days. This corresponds to a 10 g consumption of polyol per day. Plaque parameters (growth, pH, bacteria and insoluble glucans) were evaluated throughout the experimental period., Results: All parameters studied were significantly modified with gum base compared to no-gum: plaque pH increased; plaque growth, bacteria (S. mutans, S. sobrinus, A. viscosus and Lactobacillus) and insoluble glucans decreased. Maltitol and xylitol CG led similarly to a higher plaque pH (AUC, p⋜0.05) on short (at baseline after the first CG consumption) and long term (after 4 weeks of daily CG consumption), with or without saliva stimulation compared to both control and placebo groups. They led to a decrease in plaque growth (p=0.02) over the experimental period compared to controls. Moreover, they significantly reduced the concentration of 4 cariogenic bacteria species (p⋜0.05) in dental plaque compared to gum base., Conclusion: Sugar free CG sweetened with either maltitol or xylitol can similarly reduce plaque acidogenicity compared to gum base through a decrease in oral bacteria presence. The use of a gum base placebo allowed to isolate effects on parameters involved in dental caries development specific to maltitol and xylitol, and to show these effects were similar.

Purpose: This double-blind, crossover study evaluated whole plaque fluoride concentration (F), as well as whole plaque calcium concentrations (Ca) after brushing with a placebo (PD - fluoride free), low-fluoride (LFD, 513 microg F/g) and conventional (CD, 1,072 microg F/g) dentifrices., Methods: Children (n=20) were randomly assigned to brush twice daily with one of the dentifrices, during 7 days. On the 7th day, samples were collected at 1 and 12 hours after brushing. F and Ca were analyzed with an ion-selective electrode and with the Arsenazo III method, respectively. Data were analyzed by ANOVA, Tukey's test and by Pearson correlation coefficient (P< 0.05)., Results: The use of the fluoridated dentifrices significantly increased plaque [F]s 1 hour after brushing when compared to PD, returning to baseline levels 12 hours after. Positive and significant correlations were found between plaque [F] and (Ca) under most of the conditions evaluated. The mean increase in plaque [F] observed 1 hour after brushing with the CD were only about 47% higher than those obtained for the LFD. The use of a LFD promotes proportionally higher increases in plaque [F] when compared to a CD. Plaque F concentrations were also shown to be dependent on plaque Ca concentrations.

Objectives: To compare the effect of 40 seconds versus 2 minutes brushing on saliva and dental biofilm fluid fluoride in children ages 4-5 years over 1 hour., Design: This was a single-blind, cross-over, randomised, two-period clinical study in healthy children. Three days before the start of each treatment subjects received a thorough brushing and then refrained from all oral hygiene procedures. At treatment visits, after collecting baseline biofilm and saliva samples, staff brushed the occlusal surfaces of the subject's posterior teeth with a pea-sized amount (0.25 g) of NaF/silica toothpaste for the randomised time. Samples were taken at 5 minutes, 15 minutes, 30 minutes and 60 minutes after brushing and analysed for fluoride using a microanalytical methodology. There was a minimum 4-day washout period between treatments., Results: Log changes from baseline biofilm fluid and saliva fluoride were statistically significant (P < 0.05) for both brushing times at all post-brushing time-points [except 60 minutes saliva where P = 0.06 (t-test)]. Statistically significantly greater ln-AUC (area under the curve) was found for biofilm fluid and salivary fluoride after brushing for 2 minutes compared with brushing for 40 seconds over the 1-hour test period. There was a statistically significantly higher concentration of fluoride in the log change from baseline saliva levels after 5, 15, 30 and 60 minutes for the 2-minute brushing time compared with 40 seconds brushing time. There was no statistically significant difference in concentration of log change from baseline fluoride levels in biofilm fluid at each individual time-point (5, 15, 30 and 60 minutes) for the 2-minute brushing time compared with the 40-second brushing time, but significant differences were observed for 15, 30 and 60 minutes in favour of 2-minute brushing time when log biofilm fluid value was analysed., Conclusion: The findings provide further evidence for the benefits of increased duration of brushing with respect to fluoride delivery., (© 2013 FDI World Dental Federation.)

Unlabelled: This article discusses the possible cariostatic mechanisms of the action of fluoride. In the past, fluoride inhibition of caries was ascribed to reduced solubility of enamel due to incorporation of fluoride (F-) into the enamel minerals. The present evidence from clinical and laboratory studies suggests that the caries-preventive mode of action of fluoride is mainly topical. There is convincing evidence that fluoride has a major effect on demineralisation and remineralisation of dental hard tissue. The source of this fluoride could either be fluorapatite (formed due to the incorporation of fluoride into enamel) or calcium fluoride (CaF2)-like precipitates, which are formed on the enamel and in the plaque after application of topical fluoride. Calcium fluoride deposits are protected from rapid dissolution by a phosphate -protein coating of salivary origin. At lower pH, the coating is lost and an increased dissolution rate of calcium fluoride occurs. The CaF2, therefore, act as an efficient source of free fluoride ions during the cariogenic challenge. The current evidence indicates that fluoride has a direct and indirect effect on bacterial cells, although the in vivo implications of this are still not clear., Conclusion: A better understanding of the mechanisms of the action of fluoride is very important for caries prevention and control. The effectiveness of fluoride as a cariostatic agent depends on the availability of free fluoride in plaque during cariogenic challenge, i.e. during acid production. Thus, a constant supply of low levels of fluoride in biofilm/saliva/dental interference is considered the most beneficial in preventing dental caries., (Copyright © 2013 by Academy of Sciences and Arts of Bosnia and Herzegovina.)

This is a review of the need for better remineralization and of the status of calcium-based remineralizing agents for use in anti-caries toothpastes. Use of fluoride toothpastes has markedly reduced caries. However, the decline may be over or in reverse. There is a limit to what fluoride alone can do; complementary agents are needed. Using plaque as a reservoir for calcium-based agents holds promise. Plaque fluid is already supersaturated with respect to relevant calcium phosphates at neutral pH; extra calcium may lead to surface-blocking and sub-optimal lesion consolidation. However, at cariogenic pH, lesions may be more porous to the ingress of mineral, leading to fuller consolidation, and controlled release of calcium should reduce undersaturation with respect to enamel and accelerate deposition of fluorhydroxyapatite. Clinical data to validate in vitro screening models are scarce. Direct progression to in situ models may often be appropriate. The spectrum of lesion types, from softening to relatively advanced subsurface, and lesion activity should be considered. Far from being 'marketing hype', progress with calcium-based remineralizing agents is both encouraging and scientifically sound. Clinical evidence exists for the efficacy of some agents, but further unequivocal clinical data are needed before these agents might be considered 'effective' when delivered from toothpaste.

Objectives: To determine whether there are any differences in fluoride (F), calcium (Ca) or phosphate (PO(4)) concentrations in natural plaque biofilms between the upper right and left quadrants using a fluoride sustained slow-releasing device (FSSRD) placed in the upper right quadrant after 7 and 21 days. To report and validate a new methodology in measuring very low concentrations of F in dental plaque and saliva using ion chromatography., Methods: Twenty-one participants were divided into two groups with 11 participants in group one and 10 in group two. Each participant had a FSSRD attached to the upper right second permanent molar and two plaque generating devices (PGDs) attached to the upper right and left first permanent molars. The PGDs were recovered after 7 days in group one and 21 days in group two., Results: At both 7 and 21 days (right, left), F (1.081±1.517 ppm, 0.736±0.840 ppm) and (0.459±0.888 ppm, 0.203±0.139 ppm), PO(4) (1053±533 ppm, 654±246 ppm) and (865±1099 ppm, 474±304 ppm) and Ca (136±132 ppm, 74±36 ppm) and (130±109 ppm, 77±24 ppm), were higher in the quadrant containing the FSSRD but not significantly so (p>0.05). Fluoride and PO(4) fell in both quadrants between 7 and 21 days, though not significantly., Conclusions: Intriguingly while not statistically significant, 21 day plaque contained less fluoride than those investigated after 7 days. While the data was not statistically significant, it seems possible that F, Ca and PO(4) accumulated around the device to a limited extent but were washed away fairly quickly and distributed around the oral cavity., Clinical Importance: The FSSRD was found to reduce dmfs/DMFS by 76% and raise salivary F levels by ∼10 folds. This device is very helpful in reducing dental decay where compliance is impaired such as in patients with special needs. This study further investigates the anti-cariogenic effect of this device., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Unlabelled: The assessment of the fluoride kinetics in whole saliva as well as in the different salivary phases (supernatant saliva and sediment) is essential for the understanding of fluoride bioavailability., Objectives: To assess the fluoride content, provided by sodium fluoride and amine fluoride, in the supernatant saliva and in salivary sediment., Methods: Seven trained volunteers were randomly attributed to 2 groups in a cross-over design and brushed their teeth in the morning for 3 min with a product containing either sodium fluoride or amine fluoride. Saliva was collected before, immediately after tooth brushing and 30, 120, and 360 min later and measured. The samples were centrifuged 10 min at 3024 × g. Fluoride content of the supernatant saliva and of the sediment was analysed using a fluoride sensitive electrode. All subjects repeated the study cycles 2 times, and statistical analyses were made using the nonparametric sign test for related samples, the Wilcoxon-Mann-Whitney-test for independent samples., Results: There was a significant increase in fluoride immediately after tooth brushing in both groups in saliva and sediment. The distribution of fluoride between salivary sediment and supernatant saliva (ratio) varied considerably at the different collection times: decreased from 17.87 in baseline samples of saliva to 0.07 immediately and to 0.86 half an hour after tooth brushing in the sodium fluoride group and from 14.33 to 2.85 and to 3.09 in the amine fluoride group. Furthermore after 120 min and after 360 min after tooth brushing the ratio increased from 17.6 to 31.6 in the sodium fluoride group and from 20.5 to 25.76 in the amine fluoride group. No difference was found in the sediment-supernatant saliva ratio between the sodium fluoride and the amine fluoride groups 360 min after tooth brushing., Conclusion: For the assessment of fluoride kinetics in whole saliva it is necessary to pay attention to at least four factors: fluoride formulation, time after fluoride application, fluoride concentration in supernatant saliva and fluoride concentration in salivary sediment. This study was approved by the Ethical Committee of the University of Witten/Herdecke permission 21/2008., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The main objective was to investigate whether low-molecular-weight fraction of edible mushroom shiitake extract (Lentinus edodes) possesses caries-preventive properties. The study was designed as a double-blind, three-leg, cross-over, randomized, controlled clinical trial carried out on two series of volunteers at the University of Gothenburg, and the Academic Centre for Dentistry Amsterdam. Volunteers rinsed twice daily with a solution containing low-molecular-weight fraction of edible mushroom, placebo (negative control without active ingredients), or Meridol (positive control, AmF-SnF(2)) for two weeks, with a two-week washout period between each rinsing period. Changes in the acidogenicity of dental plaque before and after a sucrose challenge, shifts in microbial composition, and plaque scores were determined. Frequent rinses with shiitake reduced the metabolic activity of dental plaque. No reduction of plaque scores and no inhibition of the production of organic acids in plaque was found. Minor differences in microbial composition between test sessions were found. To conclude, the results indicate that shiitake extract has anticariogenic potential, but not to the same extent as the positive control.

Aim: To investigate the effect of the fluoride sustained slow-releasing device (FSSRD) on F levels in unstimulated saliva and undisturbed plaque biofilms over 7 days. The investigation also aimed at studying the effect of patient age on fluoride (F) concentrations in dental plaque biofilms and unstimulated saliva while using the FSSRD., Study Design: This was a randomised control double blind cross-over study., Methods: Sixty-five participants between the ages of 6-35 years took part in this study. The mean age of all the participants was 19.22 years with 24 participants aged between 6-16 years (mean age=11.8 years) and 41 participants aged between 16-35 years (mean age=23.57 years). Plaque biofilms were collected using a modification of the plaque generating device (MPGD) [Robinson et al., 1997]. During the whole study period, including a 7 day washout period before the first leg, all participants were asked to use only non-fluoridated toothpaste and to avoid where possible high fluoride containing foods or drinks. Whenever possible, the FSSRD/placebo device (PD) was attached to the second permanent molar, while the MPGD was attached to the first permanent molars in the same upper dental quadrant. At the end of each leg of the study whole, mixed unstimulated saliva was collected from all participants and analysed for F concentration., Statistics: Statistical analysis using paired sample t-test was used to compare the results of F level between test and control groups, while, Spearman's correlation coefficient was used to test the relationship between patient's age and plaque weight against F concentration in plaque and saliva., Results: There was no statistically significant difference in F concentration in plaque and saliva between the test and control groups when analysed using paired sample t-test (p>0.05). There was no correlation between patient's age and F concentration in dental plaque and saliva (p>0.05), in both the test and control groups., Conclusions: Our data showed no effect of the FSSRD in raising F concentrations in dental plaque and unstimulated whole saliva after 7 days. Such levels may require longer periods to become established.

Introduction: An increasing number of people all around the world are turning to the nature by using the natural herbal products in both prophylaxes and treatment of different diseases. Green tea with active chemical ingredients posses diverse pharmacological properties that include anti-inflammatory, anticariogenic, antioxidant and antibacterial effects., Aims: To assess the possible protective properties of green tea on oral health., Methods: The researchers used the following measurements: Streptococcus mutans count in saliva and plaque, Salivary and plaque pH values, Gingival Bleeding Index (GBI). The above-mentioned measurements were applied to a sample consists of 25 subjects before and after rinsing with green tea for 5 min (short-term study). While, S. mutans count for saliva and plaque and GBI measurements, this experimental intervention study was carried out in the El-Azhar University dental clinic., Results: The results of this study showed that there was a statistically significant difference among subjects pre- and post-rinsing with 2% green tea for 5 min concerning S. mutans count in saliva and plaque, salivary and plaque pH values and GBI., Conclusion: This study supports the effectiveness of local application of green tea as antibacterial and anticariogenic material as it decreases the acidity of the saliva and plaque, so it is a cost-effective caries prevention measures especially in developing countries., (© 2009 John Wiley & Sons A/S.)

Objective: To investigate the effects of fluoride (F), calcium-phosphate-monofluorophosphate-urea (CPMU) mineralising solution, and casein on plaque pH and calcium (Ca), phosphate (P) and F content, and the ability of plaque to induce carious lesions in enamel., Methods: Plaque microcosms were cultured in cariogenic growth conditions on enamel specimens for 28d in a "multiplaque artificial mouth". The plaques were supplied 5 times daily with 10% sucrose (1.5 ml over 6 min) over a 12h period followed by a 12h rest period. Duplicate plaques were pulsed with 0, 1000, 3000 and 5000 ppm F (1.5 ml over 6 min) or 2% w/v casein (1.25 ml over 30 min) twice daily. One of each pair was also pulsed with CPMU (1.5 ml over 6 min). Plaque pH was monitored during growth. After 28 days' culture, plaque Ca, P and F levels were quantified and lesion depth in enamel was measured by backscattered electron SEM., Results: F pulses raised the plaque pH, which was otherwise below 4 during sucrose pulsing, while CPMU hastened and raised the recovery pH. Plaque Ca, P and F levels substantially increased with increasing concentrations of applied F, particularly in the presence of CPMU (P < 0.01). In the absence of either F or CPMU, enamel lesions were formed with extensive enamel loss., Conclusions: CPMU and F supplied to plaque microcosms substantially reduce plaque cariogenicity to enamel under highly cariogenic experimental conditions. This was associated with an increase in plaque pH, plaque F and Ca levels.

The present study investigated de- and remineralization in enamel lesions under plaque fluid (PF)-like conditions using quantitative light-induced fluorescence (QLF). Preformed lesions were exposed to partially saturated lactic acid solutions, varying in pH and fluoride concentration ([F]) based on a 5 × 3 factorial study design (0/0.1/0.5/1.5/4 ppm F; pH 4.9/5.2/5.5). Average fluorescence loss (ΔF) was monitored for 11 days. Subsequently, lesions were demineralized in a partially saturated acetic acid solution for two 24-hour periods. Data were analyzed using repeated measures analysis of covariance. Lesions exposed to PF at 4 ppm F and pH 5.5 showed not only the most remineralization (ΔΔF = 28.2 ± 14.0%) for all groups after 11 days, but also the most demineralization (ΔΔF = -19.3 ± 13.5%) after subsequent acetic acid exposure. Increased [F] resulted in more remineralization, regardless of pH. Higher pH values resulted in more remineralization. No remineralization was observed in lesions exposed to F-free solutions, regardless of pH. Remineralization was noticeable under the following conditions: pH 4.9 - [F] = 4 ppm, pH 5.2 - [F] ≥ 1.5 ppm, and pH 5.5 - [F] ≥ 0.5 ppm. Overall, [F] had a stronger effect on remineralization than pH. Subsequent demineralization showed that little protection was offered by PF-like solutions, and further demineralization compared with baseline was observed on lesions not remineralized initially. [F] had a stronger effect on net mineral change than pH. The present study has shown that QLF is a valuable tool in studying lesion de- and remineralization under PF-like conditions, where [F] was shown to be more important than pH., (Copyright © 2011 S. Karger AG, Basel.)

Previous studies have indicated that the use of low-fluoride dentifrices could lead to proportionally higher plaque fluoride levels when compared with conventional dentifrices. This double-blind, randomized, crossover study determined the effects of placebo, low-fluoride, and conventional dentifrices on plaque fluoride concentrations ([F]) in children living in communities with 0.04, 0.72, and 3.36 ppm F in the drinking water. Children used the toothpastes twice daily, for 1 wk. Samples were collected 1 and 12 hrs after the last use of dentifrices and were analyzed for fluoride and calcium. Similar increases were found 1 hr after the children brushed with low-fluoride (ca. 1.9 mmol F/kg) and conventional (ca. 2.4 mmol F/kg) dentifrices in the 0.04- and 0.72-ppm-F communities. Despite the fact that the increases were less pronounced in the 3.36-ppm-F community, our results indicate that the use of a low-fluoride dentifrice promotes a proportionally higher increase in plaque [F] when compared with that achieved with a conventional dentifrice, based on dose-response considerations.

The aim of this in vivo study was to evaluate the effect of two antimicrobial mouthrinses on dental plaque acidogenicity after a sucrose challenge. Twenty subjects, with a mean age of 59 years, participated in a double-blind intraindividual randomized study. Three mouthrinses were used in 16-day rinsing periods in addition to their regular mechanical oral hygiene: a solution with essential oils (EO), solution with alcohol-free chlorhexidine (CHX) and water (negative control). The three test periods were separated by 3-month washout periods. Changes in plaque acidogenicity were evaluated after a sucrose challenge at day 0 (baseline) and at day 17 of each mouthrinse period using the microtouch method. Both CHX and EO resulted at day 17 in statistically significant less attenuated pH falls compared to the water rinse. The CHX mouthrinse resulted in the least pronounced pH values compared with EO (ns) during the whole 30-min period. When calculated as area under the curve (AUC), significantly lower values (AUC(6.2) ) were found for CHX and EO at day 17 compared to day 0. A significant difference for AUC(6.2) between CHX and water was found at day 17. No statistically significant differences were found for any of the comparisons with AUC(5.7). The results from this study indicate that both the essential oils and the alcohol-free chlorhexidine reduced plaque acidogenicity after a sucrose challenge. Large interindividual variations were observed.

Models to evaluate the anticaries potential of fluoride (F) formulations containing monofluorophosphate (MFP) should consider the release of F ion to the oral environment by its enzymatic hydrolysis. This was tested in situ, using a test plaque of a strain of Streptococcus mutans which presents high MFPase activity at pH 5.0. The test plaque was exposed to non-F or MFP (1,450 microg F/g) dentifrices and the fluid phase of the plaque was analyzed after 15, 30, 45 and 75 min. MFP concentration in the plaque fluid decreased over time after exposure to MFP dentifrice, but F ion reached 134.9 +/- 32.0 microM at 15 min and decreased significantly only at 75 min, suggesting continuous MFP hydrolysis by the test plaque., (Copyright 2010 S. Karger AG, Basel.)

Plaque 'calcium-fluoride-like' (CaF(2)-like) and fluoride deposits held by biological/bacterial calcium fluoride (Ca-F) bonds appear to be the source of cariostatic concentrations of fluoride in plaque fluid. The aim of this study was to quantify the amounts of plaque fluoride held in these reservoirs after a sodium fluoride rinse. 30 and 60 min after a 228 microg/g fluoride rinse, plaque samples were collected from 11 volunteers. Each sample was homogenized, split into 2 aliquots (aliquots 1 and 2), centrifuged, and the recovered plaque fluid combined and analyzed using microelectrodes. The plaque mass from aliquot 1 was retained. The plaque mass from aliquot 2 was extracted several times with a solution having the same fluoride, calcium and pH as the plaque fluid in order to extract the plaque CaF(2)-like deposits. The total fluoride in both aliquots was then determined. In a second experiment, the extraction completeness was examined by applying the above procedure to in vitro precipitates containing known amounts of CaF(2)-like deposits. Nearly identical fluoride concentrations were found in both plaque aliquots. The extraction of the CaF(2)-like precipitates formed in vitro removed more than 80% of these deposits. The results suggest that either CaF(2)-like deposits were not formed in plaque or, if these deposits had been formed, they were rapidly lost. The inability to form persistent amounts of CaF(2)-like deposits in plaque may account for the relatively rapid loss of plaque fluid fluoride after the use of conventional fluoride dentifrices or rinses., ((c) 2010 S. Karger AG, Basel.)

The aim of this study was to evaluate the effect, on de novo plaque formation, of rinsing with toothpaste slurries and water solutions containing a high concentration of fluoride (F). Sixteen subjects rinsed three times per day for 4 d with dentifrice slurries containing 5,000, 1,500, and 500 ppm F, while 12 subjects rinsed with water solutions containing 5,000, 1,500, 500, and 0 ppm F, and 1.5% sodium lauryl sulphate (SLS). Plaque was scored [using the Quigley & Hein index (QHI)] after each 4-d period. Plaque samples for F analysis were collected. Significantly less plaque was scored for the dentifrice slurry containing 5,000 ppm F (buccal and all surfaces) and for 1.5% SLS (buccal surfaces). The differences in plaque scores between dentifrice containing 5,000 and 1,500 ppm F were 19% for all surfaces and 33% for buccal surfaces. The difference between the water solutions containing 1.5% SLS and 1,500 ppm F for buccal surfaces was 23%; the corresponding difference for 5,000 ppm F was 17%. The dentifrice slurry containing 5,000 ppm F accumulated 56% more F in plaque. The combination of high levels of F and SLS in dentifrice reduces de novo plaque formation and increases the accumulation of F in plaque after 4 d.

Purpose: To evaluate in situ the effect and mechanisms involved in the anticariogenic effect of a calcium glycerophosphate fluoride dentifrice., Methods: In a double-blind, crossover design, a non-F dentifrice (negative control), a F dentifrice and a F dentifrice containing 0.13% CaGP were compared regarding the inhibition of enamel demineralization. Both F dentifrices contained 1500 microg F/g (w/w) as sodium monofluorophosphate (MFP). Bovine enamel blocks were mounted in contact with a S. mutans test plaque, in palatal appliances worn by 10 volunteers. 30 minutes after treatment with the dentifrices, a sucrose rinse was performed and enamel demineralization was assessed after an additional 45 minutes., Results: No significant difference was observed among groups in the calcium and inorganic phosphate concentrations in the fluid phase of the test plaque 30 minutes after the dentifrice use (P > 0.05), but F concentration was significantly higher for both F dentifrices (P < 0.05). Also, the dentifrices did not differ regarding the pH before or 5 minutes after the sugar challenge (P > 0.05). A higher mineral loss was observed for the non-F dentifrice group (P < 0.05), but no significant difference was observed between the F dentifrices containing CaGP or not (P > 0.05). Using this in situ model, the findings suggested that CaGP at the concentration tested did not enhance the inhibition of enamel demineralization promoted by F dentifrice.

Aim: This review of the literature examines the role of the natural components of saliva in maintaining tooth mineralization and the role of different casein phosphopeptide amorphous calcium phosphate-based (CPP-ACP) compounds in controlling demineralization/remineralization and their clinical applications., Background: A group of peptides, known as CPP, have been shown to stabilize calcium and phosphate preserving them in an amorphous or soluble form known as amorphous calcium phosphate (ACP). Calcium and phosphate are essential components of enamel and dentine and form highly insoluble complexes, but in the presence of CPP they remain soluble and biologically available. This CPP-ACP complex applied to teeth by means of chewing-gum, toothpaste, lozenges, mouth rinses, or sprays is able to adhere to the dental biofilm and enamel hydroxyapatite providing bioavailable calcium and phosphate ions., Review Results: Significantly high levels of calcium and phosphate have been found in both biofilm and subsurface incipient caries lesions and in lower level demineralization of enamel or dentine surfaces previously treated with CPP-ACP based compounds. When placed on the surface of a tooth with early carious lesions, pastes with CPP-ACP complexes can prevent tooth demineralization and improve enamel remineralization and enhance fluoride activity., Conclusion: Remineralization of white spot lesions has been achieved clinically by applying pastes based on these compounds, and a similar effect to self-applied fluorides has been observed in reducing the appearance of new caries lesions in patients with xerostomia., Clinical Significance: Use of CPP-ACP based compounds offers a potential for use in the prevention of dental caries.

Although the anticaries effect of fluoride (F) dentifrices is clearly established, the relative importance of F taken up by dental plaque not removed by brushing and of F products (CaF(2)-like) formed on totally cleaned enamel for the subsequent inhibition of demineralization is not known. Both effects were evaluated using conventional (1,100 microg F/g) and low-F concentration (500 microg F/g) dentifrices in a randomized, crossover, double-blind in situ study. Enamel blocks not treated or pretreated with the dentifrices to form CaF(2)-like deposits were mounted in palatal appliances in contact with a Streptococcus mutans test plaque. Volunteers brushed with non-F (negative control), low-F or conventional dentifrices and inserted the appliance in the mouth. F concentration in the fluid and solid phases of the test plaque was determined after 30 min, and a rinse with 20% sucrose solution was performed. After additional 45 min, plaque was collected and the loss of surface hardness at different test-plaque depths was measured. CaF(2)-like deposition on enamel and F taken up by plaque due to the use of F dentifrices were able to significantly increase F concentration in the fluid phase of the test plaque, but only the latter significantly reduced the loss of hardness because of the 20-30 times higher F concentration. Also, significant differences between the low-F and conventional dentifrices were observed for F on enamel, in plaque and on the subsequent loss of hardness. The results suggest that uptake of F by dental plaque not removed by brushing may be the main cause of the anticaries effect of F dentifrices., ((c) 2009 S. Karger AG, Basel.)

A total of 26 healthy volunteers participated in this randomized 4-leg crossover study designed to measure fluoride (F) retention in interdental plaque and saliva. Two NaF dentifrices (5,000 and 1,450 ppm F) were used, with and without postbrushing water rinsing. The 4 tooth brushing methods were carried out twice a day during 2 weeks. Interdental plaque was collected from all proximal sites after each method, using dental floss. Immediately after the plaque sampling, the subjects were asked to brush their teeth with the same toothpaste and use the postbrushing water rinsing procedure as previously. Proximal saliva was collected from 4 interdental sites, using small paper points, before and up to 60 min after the brushing. The present study showed that the 5,000 ppm F toothpaste without postbrushing water rinsing resulted in the highest F concentration in both plaque and saliva and the 1,450 ppm F toothpaste with water rinsing in the lowest. The difference in the area under the curve of saliva F concentration versus time between the 2 methods was 4.2 times (p<0.001). The corresponding difference in F concentration per unit weight of plaque (n=16) was 2.75 times (p<0.05). Water rinsing immediately after tooth brushing with 5,000 ppm reduced the F concentration in saliva by 2.4 times (p<0.001). The difference in F values in saliva between 5,000/rinsing and 1,450/no rinsing was minor and not significant. The increase of F in both proximal saliva and plaque, using a dentifrice with 5,000 ppm F without postbrushing water rinsing, may be of clinical importance., (Copyright 2009 S. Karger AG, Basel.)

Purpose: The aim of this in situ double-blind randomised crossover study was to investigate the effect of calcium (Ca) pre-rinse on the composition of plaque and on enamel prior to the use of fluoride (F) dentifrice., Materials and Methods: During four phases (14 days each) of this study, 10 volunteers had agreed to wear dental appliances containing two healthy bovine enamel blocks. A fresh solution containing 20% weight/volume (w/v) sucrose was dripped on the enamel blocks ex vivo for 5 min three times a day. Subsequently, the appliances were replaced in the mouth, and the volunteers rinsed their mouth with 10 mL of a Ca (150 mmol/L) or a placebo rinse (1 min). In sequence, a slurry (1:3 w/v) of F (1030 ppm) or placebo dentifrice was dripped onto the blocks ex vivo for 1 min. During this time, the volunteers brushed their teeth with the respective dentifrice. The appliances were replaced in the mouth, and the volunteers rinsed their mouth with water. The plaque formed on the blocks was analysed for F and Ca. The enamel demineralisation as well as the incorporation of F on enamel was evaluated by cross-sectional microhardness and alkali-soluble F analysis, respectively. Data were tested using analysis of variance (P < 0.05)., Results: The Ca pre-rinse prior to the use of the F dentifrice led to a three- and sixfold increase in the plaque F and Ca concentrations, respectively. It also did not have any additive effect on the F content on the enamel and the demineralisation of the enamel, in comparison with the use of F dentifrice alone., Conclusions: A Ca lactate rinse used prior to the F dentifrice was able to change the mineral content in the plaque, but it was unable to prevent enamel demineralisation.

To evaluate the influence of dentifrice pH and fluoride (F) concentration on F uptake by plaque and nails, two sets of 5- to 6-year-old children were randomly allocated into four groups, according to the type of dentifrice they had been using for 1 year: (1) experimental liquid dentifrice (ELD), 1,100 ppm F, pH 7.0; (2) ELD, 1,100 ppm F, pH 4.5; (3) ELD, 550 ppm F, pH 4.5, and (4) commercial toothpaste, 1,100 ppm F, pH 7.0. In one set of children, nails were clipped. In the second, plaque samples were collected 1 h after the last use of dentifrice. F concentration in plaque and nails was analyzed. Plaque F concentration was significantly lower in group 4 than in groups 1-3. Nail F concentration was significantly higher in group 4, and significantly lower in group 3, than in group 1 or 2. Plaque F uptake was influenced significantly by dentifrice consistency and nonsignificantly by pH and F concentration. Reduction of dentifrice pH did not affect nail F concentration., (2009 S. Karger AG, Basel.)

Objectives: The aim of this study was to compare the morphological appearance and the molecular composition of intraoral integuments formed in situ on germanium (Ge) crystals in the presence or absence of the commercially available casein-phosphopeptide-amorphous calcium phosphate (CPP-ACP) cream agent., Methods: Six volunteers participated in the study. Impression of maxillary arch was taken for each patient, and a removable orthodontic appliance with a custom-made retainer was fabricated. Clean Ge crystals mounted in the retainers were placed intraorally for 30 min, 8, 24 h and 1-week period. The free sampling surface of another series of Ge crystals was treated with the commercial CPP-ACP agent (Tooth Mousse), mounted in the retainers and placed intraorally for the same period as above. The free exposed surfaces in oral cavity of the specimens in all subjects were examined as follows: (a) reflected light microscopy, (b) micro-MIR-FTIR spectroscopy and (c) scanning electron microscopy (SEM) plus energy-dispersive X-ray microanalysis analysis (XEDS)., Results: The light microscopic observations revealed that there was a delay in biofilm formation on Ge surfaces treated with agent in comparison to those ones without treatment. The micro-MIR-FTIR spectra from the surfaces with Tooth Mousse showed an increase in intensity and a left shift of PO(4)(3-) peak (1064 cm(-1)). Finally, the PO(4)(3-) peak at lower bands (564 cm(-1)) and the low-wave bands at 525-530 cm(-1) increased at 1-week interval. The SEM revealed the dendritic development of microbes. The XEDS analysis showed a significant increase in Cl/O, K/O, K/Cl and a decrease in Ca/O and P/O ratios on the crystal Ge without surface treatment. On contrary, on the crystal Ge with surface treatment an increase in Ca/O, Ca/P and a decrease in K/Cl ratios were found., Conclusion: The results show that the presence of CPP-ACP agent delays the biofilm formation and favored the nucleation and crystallization of calcium phosphates, possibly in apatitic form, in matured biofilms.

This article discusses fluoride-releasing materials, including their caries-inhibiting properties and clinical longevity, as well as provides useful application tips. Based on results from clinical trials, there is growing evidence that fluoride-releasing materials, particularly glass ionomers, reduce the occurrence of recurrent caries. As such, they should be employed-especially in the case of high caries-risk patients-as part of an overall treatment plan for maximum care.

Objective: This study determined the effect of Hop polyphenols (HPP) on water-insoluble glucan (WIG), which is a major component of dental plaque along with microorganisms, and the effect of HPP-containing tablets on the growth of dental plaque., Methods: The effects of HPP on Streptococcus mutans MT8148 were determined. HPP concentrations employed in this study were 0% (as the HPP control), 0.001%, 0.01%, 0.1%, and 0.5%. The average result of six independent experiments was obtained at each concentration of HPP. Suppression of plaque formation in vivo was examined by a clinical trial that was designed as a randomized, single-blind, three-treatment study using 28 healthy subjects. The subjects used either 20 mg or seven mg HPP-containing tablets representing high and low dosages, respectively. The composition of each tablet was similar, except for the level of HPP; the control tablet had none. For the treatment period, subjects took one tablet seven times a day (before breakfast, after each meal, between meals, and at bedtime) for three days. The tablets were dissolved in the mouth and naturally swallowed. Plaque levels were then assessed for the subjects in the three groups., Results: In vitro, after 24-hour incubation, 0.5% HPP significantly reduced the growth of S. mutans compared to the control (p < 0.01). After 18-hour incubation, HPP at 0.1% and 0.5% significantly reduced lactic acid production (p < 0.05 and p < 0.001, respectively), and HPP at 0.01%, 0.1%, and 0.5% also suppressed WIG production (p < 0.01, p < 0.001 and p < 0.001, respectively). In vivo, the effect of HPP-containing tablets (seven times a day) on three-day dental plaque regrowth was assessed by the plaque scoring system (PSS). The high-dosage group using 20 mg HPP tablets exhibited a reduction in PSS (1.37 +/- 0.48 vs. 2.41 +/- 1.15 in the control group, p < 0.05)., Conclusion: It was concluded that HPP tablets might be a significant means of delivering HPP onto tooth surfaces to prevent dental plaque formation.

In this study, the effects of 0.2% sodium fluoride mouthwash solution on calcium, phosphate and fluoride ion contents of saliva and microbial plaque was assessed. Fourteen volunteer students (7-12 years of age) of a boarding educational centre in Kerman City (Iran) were selected and under defined conditions, their saliva and plaque samples were collected. The concentrations of fluoride, calcium and phosphate ions of the samples were determined, and after 14 days, under the same conditions, the students were asked to rinse their mouth with 0.2% sodium fluoride mouthwash solution. The second set of saliva and plaque samples were collected and the concentrations of the ions were determined. Data was analyzed using paired t-test and the results were presented as tables. P < 0.05 was considered as statistically significant. After using 0.2% sodium fluoride mouthwash solution, a significant increase was observed in the F 2 ion concentration both plaque ( P P < 0.000) of all the studied subjects, while the concentration of phosphate decreased in both saliva and plaque; however, this decrease was significant only in plaque ( P < 0.01). The calcium ion concentration decreased in both plaque and saliva; however, in none of them, the decrease was significant ( P> 0.09 and P> 0.2, respectively).

Objectives: The effect of multiple daily applications of a prophylactic gel, with buffering substances, on plaque acidogenicity in elderly institutionalised individuals was evaluated., Background: Many elderly suffer from reduced salivary flow, poor oral hygiene and increased levels of cariogenic bacteria and are considered to be at an increased risk for coronal and root caries. Reinforcing the buffering capacity of dental plaque by the addition of substances such as bicarbonate and phosphates may decrease their caries activity., Materials and Methods: Fourteen elderly, with subjective dry mouth, were treated for 16-day-periods at random with: (i) Profylin fluoride gel with buffering components; (ii) Profylin fluoride gel without buffering components and (iii) rinsing with water. Applications were made four times a day and each period was followed by a 2-week wash-out period. The plaque pH was registered after a carbohydrate challenge and the following were recorded before and after each test period: stimulated salivary secretion rate, buffer capacity, number Colony Farming Units (CFU) mutans streptococci, lactobacilli and a sample of Candida albicans on oral mucosa., Results: Eleven participants (mean age 76.6 years) fulfilled the study. Changes in plaque pH measurements, when calculated as area under the curve (AUC(6.2) and AUC(5.7)) values (pH x min), before and after each of the three treatments, showed no significant differences. A tendency to a higher plaque acidogenicity and amount of cariogenic microorganisms was found after the gel treatments. C. albicans was found in low levels., Conclusion: Frequent applications of the gel did not result in an improved neutralising effect in the elderly. This may be caused by a combination of several factors, such as the level of oral dryness of the individuals and low solubility, release and retention of the gel substances in plaque. Instead, an increased plaque acidogenicity was noted.

Objectives: The purpose of this article was to review the fluoride release and recharge capabilities, and antibacterial properties, of fluoride-releasing dental restoratives, and discuss the current status concerning the prevention or inhibition of caries development and progression., Methods: Information from original scientific full papers or reviews listed in PubMed (search term: fluoride release AND (restorative OR glass-ionomer OR compomer OR polyacid-modified composite resin OR composite OR amalgam)), published from 1980 to 2004, was included in the review. Papers dealing with endodontic or orthodontic topics were not taken into consideration. Clinical studies concerning secondary caries development were only included when performed in split-mouth design with an observation period of at least three years., Results: Fluoride-containing dental materials show clear differences in the fluoride release and uptake characteristics. Short- and long-term fluoride releases from restoratives are related to their matrices, setting mechanisms and fluoride content and depend on several environmental conditions. Fluoride-releasing materials may act as a fluoride reservoir and may increase the fluoride level in saliva, plaque and dental hard tissues. However, clinical studies exhibited conflicting data as to whether or not these materials significantly prevent or inhibit secondary caries and affect the growth of caries-associated bacteria compared to non-fluoridated restoratives., Significance: Fluoride release and uptake characteristics depend on the matrices, fillers and fluoride content as well as on the setting mechanisms and environmental conditions of the restoratives. Fluoride-releasing materials, predominantly glass-ionomers and compomers, did show cariostatic properties and may affect bacterial metabolism under simulated cariogenic conditions in vitro. However, it is not proven by prospective clinical studies whether the incidence of secondary caries can be significantly reduced by the fluoride release of restorative materials.

Previous work showed that a single application of 40% chlorhexidine varnish, EC40, reduced plaque acidogenicity upon sucrose challenge during less than 3 weeks. It was questioned whether lactic acid production could be reduced significantly longer when the treatment was intensified. Therefore, the effects of three consecutive EC40 applications on plaque acidogenicity were evaluated. Nine subjects who participated in the previous study received three full mouth EC40 applications within 1 week. Before the first application and up to 9 weeks after the third application, plaque samples were taken after a 10% sucrose rinse and analyzed for organic acids with capillary electrophoresis. At baseline, the mean provoked lactic acid concentration was 1.64 (+/-0.69) micromol/mg protein. At the first and seventh day after the third application, there was too little plaque to measure acid concentrations. At 2 weeks after the third application, lactic acid concentrations were significantly reduced (p < 0.05). The acid concentrations 3 weeks after the third application (1.61 (+/-0.99) micromol/mg protein) did not differ from the values at baseline (paired T test, p > 0.05). We conclude that a triple 40% chlorhexidine varnish treatment did not affect plaque acidogenicity for more than 3 weeks. From comparison with a previous study, we conclude that the triple treatment with EC40 within 1 week was not more effective in reducing plaque acidogenicity than the single one.

Plaque fluoride concentrations ([F]) are directly related to plaque calcium concentrations [Ca]. Attempts to increase plaque F uptake from dentifrices or rinses have used methods designed to increase plaque [Ca] but with inconsistent results. This double-blind, double-crossover study tested the effect of a 150 mM calcium lactate rinse used prior to brushing with placebo or fluoridated dentifrices (1030 p.p.m. as NaF) on plaque and salivary [F] and [Ca]. Sixteen children (8-10 yr of age) were randomly assigned to four different groups according to the four treatments (placebo dentifrice or fluoridated dentifrice preceded by calcium lactate or deionized water prerinses). Plaque and saliva were collected 1 and 12 h after brushing on day 7 after starting to use the dentifrices. F was determined using the electrode and Ca was determined using atomic absorption spectrometry. Plaque and salivary [Ca] were not significantly increased after use of the calcium lactate prerinse, except for plaque [Ca] 1 h after the use of the placebo dentifrice. A significant increase in salivary [F] was associated with the calcium lactate prerinse only at 1 h after the use of the fluoridated dentifrice. The the calcium lactate prerinse did not significantly affect plaque [F] under any condition.

The aim of this study was to evaluate the effect of a new prophylactic gel on plaque pH and plaque fluoride concentration. Twelve participants with normal (n=6, >or=0.7 ml/min) and low (n=6, <0.7 ml/min) stimulated whole salivary secretion rate were included. After 3 days of plaque accumulation, at random the participants were (1) treated with Profylin fluoride gel with buffering components (active gel), (2) treated with Profylin fluoride gel without buffering components (placebo gel), (3) asked to rinse with water, and (4) given no treatment. All test series were followed by rinsing with a nutrition solution; after which registration of plaque pH was performed during 60 min. There were two drop outs with low salivary secretion rate in the water session. The overall least pronounced pH fall was found after the use of the prophylactic gel. Significant differences between the prophylactic gel and the placebo gel were found for the participants with normal secretion rate. Fluoride plaque concentrations evaluated in 12 individuals after (1) application of the active gel, (2) rinsing with 0.2% NaF, and (3) rinsing with water showed significantly higher values after rinsing with the NaF solution. It can be concluded that application of the active gel, particularly in subjects with normal salivary secretion rate, in general, buffered plaque pH to higher levels. Factors like concentration of buffering agent and solubility of the gel need to be further evaluated to improve the effect.

The aim of the present study was to assess fluoride concentrations in unstimulated saliva and buccal dental plaque 6 h after an oral hygiene procedure that consisted of brushing with an AmF/SnF2 dentifrice and different post-brush rinsing protocols: expectorating the excess of dentifrice foam and rinsing with tap water, expectorating only, or rinsing with 10 ml AmF/SnF2 mouthwash. The fluoride concentrations in plaque and saliva were increased after all three experimental protocols compared to F-free periods. The increase of the fluoride concentration in saliva was more pronounced after AmF/SnF2 mouthrinse as compared to rinsing with water and expectorating the excess of dentifrice foam. Such an effect was not seen in dental plaque. It is concluded that the potentially beneficial effect of not rinsing or fluoride rinsing after tooth brushing is not reflected in an increased fluoride concentration in newly formed dental plaque 6 h after brushing., (Copyright 2006 S. Karger AG, Basel.)

The usefulness of fluoride-releasing restorations in secondary caries prevention may be questioned because of the presence of other common sources of fluoride and because of ageing of the restorations. This study tested the hypothesis that glass-ionomer cement restorations, either aged or unaged, do not prevent secondary root caries, when fluoride dentifrice is frequently used. Sixteen volunteers wore palatal appliances in two phases of 14 days, according to a 2 x 2 crossover design. In each phase the appliance was loaded with bovine root dentine slabs restored with either glass-ionomer or resin composite, either aged or unaged. Specimens were exposed to cariogenic challenge 4 times/day and to fluoridated dentifrice 3 times/day. The fluoride content in the biofilm (FB) formed on slabs and the mineral loss (DeltaZ) around the restorations were analysed. No differences were found between restorative materials regarding the FB and the DeltaZ, for either aged (p = 0.792 and p = 0.645, respectively) or unaged (p = 1.00 and p = 0.278, respectively) groups. Under the cariogenic and fluoride dentifrice exposure conditions of this study, the glass-ionomer restoration, either aged or unaged, did not provide additional protection against secondary root caries., (Copyright 2006 S. Karger AG, Basel.)

Objectives: Aiming to contribute to the study of mechanisms involved in the anticariogenic properties of dental materials, this study assessed the suitability of a short-term in situ model to evaluate the anticariogenic potential of ionomeric materials., Methods: The study used a 3-phase crossover, double blind design, and in each phase eight volunteers wore palatal appliances containing four enamel blocks restored with one of the following materials: composite resin (CR-Z250) (negative control), a conventional glass ionomer cement (GIC-Ketac-Fil) or a resin-modified GIC (RM-GIC-Vitremer). The restored blocks were covered with a "test plaque" of S. mutans, placed in palatal appliances and a cariogenic challenge was made during 1 min with 20% sucrose solution. After 45 min, test plaque was collected for fluoride (F) analysis. Enamel surface microhardness was previously determined at one side of the restoration and the percentage of surface microhardness change (%SMC) in relation to baseline (other side) was calculated. F concentration in enamel was also evaluated., Results: Split-plot ANOVA showed a statistically lower %SMC on enamel around the ionomeric materials than around the CR (p<0.05). This result was supported by a statistically higher F concentration in test plaque (P<0.001) and in enamel (P<0.001) restored with the ionomeric materials when compared to the CR., Conclusions: The results suggest that the short-term in situ model tested is useful for studying the anticariogenic potential of dental materials that release fluoride.

Caries occurs at inaccessible stagnation sites where plaque removal is difficult. Here, the penetration through plaque of protective components, such as fluoride, is likely to be crucial in caries inhibition. We hypothesized that topically applied fluoride would readily penetrate such plaque deposits. In this study, plaque biofilms generated in vivo on natural enamel surfaces were exposed to NaF (1000 ppm F-) for 30 or 120 sec (equivalent to toothbrushing) or for 30 min. Biofilms were then sectioned throughout their depth, and the fluoride content of each section was determined with the use of a fluoride electrode. Exposure to NaF for 30 or 120 sec increased plaque fluoride concentrations near the saliva interface, while concentrations near the enamel surface remained low. Fluoride penetration increased with duration of NaF exposure. Removal of exogenous fluoride resulted in fluoride loss and redistribution. Penetration of fluoride into plaque biofilms during brief topical exposure is restricted, which may limit anti-caries efficacy.

Based on root caries data and oral sugar clearance pattern, vestibular surfaces of upper incisors and lower molars may be regarded as risk areas along with the proximal surfaces. The aim of the present study was to use this information in improving fluoride tablet programs for the elderly. Six healthy elderly males with full dental arches took part. Flavored and unflavored tablets dissolved passively either under the tongue or in the vestibule close to the root caries risk areas. Salivary fluoride was determined at five to six intra-oral sites with a micro-sampling technique at intervals up to 10 min tablet use. Plaque samples were collected from single tooth surfaces before and after tablet use, and analyzed for total fluoride and total protein by micro-techniques. Salivary fluoride exposure to root caries risk areas was strongly increased when fluoride tablets were placed in the vestibule in these areas. The unflavored tablet gave higher fluoride retention in saliva than did the flavored brand. Plaque fluoride levels tended to be above baseline in the first couple of hours after tablet use, and then to decline. In the caries risk areas, at vestibular surfaces of lower posterior and upper incisor teeth, most of the fluoride taken up in plaque had been lost after 5 h and a bread meal, whereas in the non-risk areas it was largely retained. The study demonstrated that fluoride exposures to the vestibular caries risk areas can be strongly increased by placing fluoride tablets close to them. An unflavored tablet seemed to give higher exposures than a flavored one. The rapid loss of fluoride from plaque in slow clearance risk areas indicates that more than one daily treatment would be required for elderly caries risk subjects.

The results of a recent study by Whitford et al. [Caries Res 2002;36:256-265] with subjects whose drinking water was fluoridated led to two major conclusions: (1) Compared to the use of a placebo dentifrice, plaque fluoride concentrations ([F]) throughout much of the day are not significantly increased by the use of an F dentifrice but (2) they are positively related to plaque [Ca] (p = 0.0001). The present double-blind, double-crossover study with 16 subjects used the same protocol and was done to: (1) determine the effects of the use of an F dentifrice on salivary and plaque [F] in a community without water fluoridation and (2) further examine the relationship between plaque [Ca] and [F]. Following the use of an F dentifrice or placebo for one week, whole saliva and plaque were collected 1.0 and 12 h after the last use of the products. The study was repeated to include rinsing with a 20 mmol/l CaCl(2) solution immediately before the use of the dentifrices. The CaCl(2) rinse had only minor effects on salivary [Ca] and [F] and none on the plaque concentrations. Unlike the results found in the fluoridated community, all salivary and plaque [F] associated with the use of the F dentifrice were significantly higher than those associated with the use of the placebo. The results suggest that the cariostatic effectiveness of an F dentifrice should be greater in areas without water fluoridation. As noted previously, plaque [F] were positively related to plaque [Ca] (p = 0.0001)., (Copyright (c) 2005 S. Karger AG, Basel.)

Aim: To summarise clinical support for the anti-caries efficacy of fluoride toothpastes containing sodium monofluorophosphate (SMFP) and to discuss the possible means by which the abrasive particles in calcium carbonate-based SMFP toothpastes might complement and/or enhance fluoride efficacy., Background: The anti-caries efficacy of fluoride has been proven beyond any reasonable doubt, and the efficacy of SMFP, when incorporated into a variety of compatible toothpaste formulations, has been established in numerous clinical trials. Calcium carbonate-based toothpastes may also influence caries by effecting an increase in plaque calcium levels; an inverse relationship between plaque calcium and caries is well-established. It has also been reported that plaque fluoride levels are dependent on plaque calcium levels. Hence elevated plaque calcium resulting from the use of calcium carbonate-based toothpastes has the potential to elevate plaque fluoride, itself linked to reduced caries experience. It has been shown that calcium carbonate particles are retained by plaque and this may also influence caries by neutralising harmful plaque acids and concurrently liberating calcium., Conclusion: Fluoride delivered from calcium carbonate-based SMFP toothpastes is an effective means of reducing caries. Further, calcium carbonate may confer additional benefits through elevation of oral calcium levels and neutralisation of plaque-acids.