Experimental Dentifrice Research Articles

The effect of home-use and in-office bleaching treatments combined with experimental desensitizing agents on enamel and dentin.

Objective:This study aimed to evaluate in vitro the effect of formulations containing Biosilicate to treat enamel and dentin bovine samples exposed to dental bleaching agents.Materials and Methods:On enamel and dentin bleached with commercial gels containing 16% carbamide peroxide (CP) (14 days/4 h) or 35% hydrogen peroxide (single session/45 min), desensitizing dentifrices (Sensodyne®; experimental dentifrice of Biosilicate®; Odontis RX®; Sorriso®) were applied along 14 days and desensitizing pastes (Biosilicate®/water 1:1; Dessensebilize NanoP®; Bioglass type 45S5/water 1:1) were applied on days 1, 3, 7, 10 and 14. Distilled water was the control. Microhardness (MH) and roughness measurements were the variables measured on the samples before and after the treatments. Student's t-test analyzed differences before and after the treatments. Two-way analysis of variance and post-hoc Tukey test analyzed differences among the factors desensitizing, bleaching agents and substrate.Results:Tukey test showed no differences in roughness for both bleaching treatments and among the desensitizing agents (P > 0.05). Differences in MH appeared on enamel treated with in-home bleaching when control group (lower values) was compared with Sensodyne, Biosilicate dentifrice, Biosilicate paste, and Bioglass paste (higher values). Comparisons between desensitizing agents on dentin treated with both bleaching gels showed no statistical differences.Conclusions:The effect of formulations containing Biosilicate (Biosilicate dentifrice and paste) was significant in the MH of enamel bleached with 16% CP.

In vitro antimicrobial activity of an experimental dentifrice based on Ricinus communis.

This study evaluated the antimicrobial activity of a Ricinus communis-based experimental dentifrice for denture hygiene against the following standard strains: Staphylococcus aureus, Escherichia coli, Streptococcus mutans, Enterococcus faecalis, Candida albicans and Candida glabrata. The minimum inhibitory concentration (MIC) assay was performed with R. communis in pure oil at 2.5%. Only E. coli was not inhibited by R. communis, but the MIC (0.0781%) was effective against the other microorganisms. From these results it was determined the R. communis concentrations for experimental dentifrices, 1, 2, 5 and 10%, which were evaluated by the test-well diffusion in agar. The commercial dentifrices Colgate, Trihydral and Corega Brite were tested for comparative purposes. The diameter of the zones of bacterial growth inhibition produced around the wells was measured (in mm) with a rule under reflected light. Data were analyzed statistically by analysis of variance and Tukey's post-hoc test (α=0.05). Neither the commercial nor the experimental dentifrices were effective against E. coli. The experimental dentifrices containing R. communis at 2, 5 and 10% presented action against S. mutans, S. aureaus and E. faecallis. The experimental dentifrices showed no antimicrobial activity against Candida spp. and E. coli in any of the tested concentrations. Trihydral was the most effective. Comparing the experimental dentifrices, the product with 10% R. communis produced the largest zones of bacterial growth inhibition and had similar antimicrobial activity to the commercial dentifrices, except against S. aureus.

Efficacy of a Commercial Dentifrice Containing 2% Strontium Chloride and 5% Potassium Nitrate for Dentin Hypersensitivity: A 3-Day Clinical Study in Adults in China

BackgroundStudies of dentifrices containing strontium chloride or potassium nitrate have documented the clinical efficacy of these formulations for dentin hypersensitivity (DH), but few studies have evaluated dentifrices containing both active ingredients. ObjectiveThe objective of this study was to compare the effects on DH of a dentifrice containing 2% strontium chloride and 5% potassium nitrate in a silica base (experimental dentifrice) with those of a dentifrice containing the same silica base without any active ingredient (control dentifrice). MethodsMale and female patients aged 20 to 65 years with DH were eligible to participate in this randomized, double-blind, placebo-controlled study in China. Patients were assigned to receive the experimental or control dentifrice. At baseline, immediately after topical dentifrice use, and after 3 days, patients received an oral examination of their hard and soft tissues, followed by an evaluation of DH that used the Yeaple Probe to measure tactile hypersensitivity and the Schiff Cold Air Scale to measure the perception of pain from an air blast stimulus. Adverse events (in particular, discomfort while brushing or alteration in taste) in the oral hard or soft tissues were monitored throughout the study. ResultsA total of 81 patients were enrolled (40 in the experimental group; 41 in the control group), of whom 79 (55 women; 24 men) completed the study. After topical use, the experimental group had a significantly higher mean (SD) tactile hypersensitivity score (19.47 [14.69] vs 14.27 [5.76]; P = 0.047) and a significantly lower mean air blast hypersensitivity score (1.93 [0.51] vs 2.22 [0.60]; P = 0.026) than did the control group. After 3 days, the experimental group had a significantly higher mean tactile hypersensitivity score (19.87 [14.95] vs 14.51 [6.00]; P = 0.045) and a significantly lower air blast hypersensitivity score (1.80 [0.56] and 2.13 [0.60]; P = 0.014) than the control group. After topical use and after 3 days, the experimental group had increases from baseline in tactile scores of 54.04% and 56.67%, respectively (both, P = 0.001) and reductions from baseline in air blast scores of 18.51% and 24.21% (both, P < 0.001); the control group had increases in tactile scores of 21.14% and 21.54% (P = 0.022 and P = 0.007) and reductions in air blast scores of 10.24% and 13.41% (P = 0.001 and P < 0.001). No adverse events were reported throughout the study. ConclusionIn these patients with DH in China, the dentifrice containing 2% strontium chloride and 5% potassium nitrate was efficacious in reducing DH when used instantly after topical dentifrice use and after 3 days of use. Clinicaltrials.gov identifier: NCT01426360.

Evaluation of the Abrasiveness of Dentifrices for Complete Dentures

This study analyzed the surface roughness and weight loss in Plex Glass specimens caused by dentifrices, one conventional (Sorriso) and three specific for dentures. Specimens (n = 6) of Plex Glass were divided into 5 groups including: negative control (water); positive control 1 (Sorriso) and 2 (Corega Brite); Experimental 1 (containing Chloramine T, antimicrobial agent); and Experimental 2 (containing Zonyl, detergent). Brushing was performed in a toothbrushing machine (Pepsodent) with a soft brush and a suspension of toothpaste and distilled water for 300 minutes, representing 6 years of brushing. Weight was measured initially and after the trial period; roughness was measured after the trial period only. The results of roughness and weight loss were analyzed using ANOVA and Tukey tests at 5%. The negative control (2.82 +/- 4.41 mg) showed the lowest weight loss. Experimental 1 (13.62 +/- 4.29 mg) and Experimental 2 (15.4 +/- 5.80 mg) were equal statistically, and Sorriso (23.22 +/- 7.23 mg) and Corega (28.83 +/- 6.34 mg) produced the greatest weight loss. Concerning roughness, the negative control group (0.03 +/- 0.01 microm) showed the lowest value. No significant differences were found between Corega (13.43 +/- 1.65 microm), Experimental 1 (12.28 +/- 0.85 microm), and Experimental 2 (10.68 +/- 2.56 microm). The Sorriso toothpaste produced the greatest amount of surface roughness (19.15 +/- 2.36 microm). Of the tested dentifrices, the experimental preparations proved to be the least abrasive and resulted in the lowest weight loss after brushing of the acrylic. Based on these findings, the use of these experimental dentifrices is advocated. Further evaluation based on the ability of these preparations to remove biofilms is required.

Effect of Different Fluoride Concentrations of Experimental Dentifrices on Enamel Erosion and Abrasion

It has been suggested that fluoride products are able to reduce erosive tooth wear. Thus, the purpose of this in vitro study was to evaluate the effect of dentifrices with different fluoride concentrations as well as of a low-fluoridated dentifrice supplemented with trimetaphosphate (TMP) on enamel erosion and abrasion. One hundred twenty bovine enamel blocks were assigned to the following experimental dentifrices: placebo, 1,100 µg F/g, 500 µg F/g plus 3% TMP and 5,000 µg F/g. The groups of enamel blocks were additionally subdivided into conditions of erosion (ERO) and of erosion plus abrasion (ERO + ABR). For 7 days, the blocks were subjected to erosive challenges (immersion in Sprite® 4 times a day for 5 min each time) followed by a remineralizing period (immersion in artificial saliva between erosive challenges for 2 h). After each erosive challenge, the blocks were exposed to slurries of the dentifrices (10 ml/sample for 15 s). Sixty of the blocks were additionally abraded by brushing using an electric toothbrush (15 s). The alterations of the enamel were quantified using the Knoop hardness test and profilometry (measurements in micrometers). The data were analyzed using a 2-way ANOVA test followed by a Bonferroni correction (p < 0.05). In in vitro conditions, the 5,000 µg F/g and 500 µg F/g plus 3% TMP dentifrices had a greater protective effect when compared with the 1,100 µg F/g dentifrice, under both ERO and ERO + ABR conditions. The results suggest that dentifrices alone are not capable of completely inhibiting tooth wear.

Preventive Effect of Commercial Desensitizing Toothpastes on Bovine Enamel Erosion in vitro

This study evaluated in vitro commercial desensitizing toothpastes with respect to the prevention of erosion and explored the effect of their agents alone or in combination with fluoride. Bovine enamel blocks were randomly allocated to five groups of 20 and exposed to: Sensodyne ProNamel (1,425 ppm F as NaF, 5% KNO₃), Sensodyne Original (no fluoride, 10% SrCl₂), Colgate Sensitive (1,450 ppm F as sodium monofluorophosphate, 5% K citrate), Crest (fluoride-only toothpaste, 1,100 ppm F as NaF) and water (negative control). A second experiment was conducted with experimental dentifrices containing fluoride (NaF, 1,100 ppm F), 10% SrCl₂, 5% KNO₃or 5% K citrate alone or the latter three combined with F. The samples were submitted to four cycles, alternating demineralization (cola, 10 min) and remineralization (artificial saliva, 1 h). Before and between cyclic de- and remineralization, blocks were treated with slurries of the respective toothpastes or water (1 min). Erosive tissue loss was analyzed by profilometry. Data were analyzed by Kruskal-Wallis and Dunn’s tests (p < 0.05). The mean erosion depth (± SE, µm) was significantly less for Colgate Sensitive (0.04 ± 0.00), Sensodyne Original (0.06 ± 0.01) and Crest (0.07 ± 0.01) than for Sensodyne ProNamel (2.36 ± 0.25) or water (2.92 ± 0.24), which did not significantly differ from each other. Both F and the desensitizing agents alone reduced erosion, but no additive effect was found. In addition, the combination of F and KNO₃ did not reduce erosion. These in vitro results suggest that the presence of fluoride or desensitizing substances in toothpastes, alone or in combination, can reduce erosion of enamel, but this is not valid for all the formulations.

A Clinical Assessment of the Efficacy of a Stannous-Containing Sodium Fluoride Dentifrice on Dentinal Hypersensitivity

To measure the desensitizing benefits of an experimental stannous-containing sodium fluoride dentifrice versus a regular sodium fluoride negative control. This study was a randomized, double-blind, parallel group, four-week clinical trial. Subjects reporting dentinal hypersensitivity were enrolled and randomized to the experimental dentifrice or the control dentifrice to use twice daily for four weeks. Efficacy assessments (Air Blast) were performed at baseline and weeks two and four. Separate analyses were performed for the two most sensitive teeth at baseline and for all 12 teeth. Results for weeks two and four combined also were analyzed. Thirty-one subjects were included in the analyses. For the two most sensitive teeth, the experimental dentifrice showed statistically significantly less sensitivity (p<0.05) versus the control at weeks two and four and for weeks two and four combined. The sensitivity reduction ranged from 24.9% to 28.4% over the control. For all 12 teeth, the experimental group had statistically significantly (p<0.03) lower sensitivity scores versus the control group at week two and weeks two and four combined. The experimental dentifrice demonstrated significant desensitizing advantages versus the control. This stannous-containing sodium fluoride dentifrice provides an effective treatment for patients with dentinal hypersensitivity, significantly reducing sensitivity versus a negative control in this four-week trial.

In vitro evaluation of the abrasiveness of acidic dentifrices

This in vitro study evaluated the abrasiveness of acidic fluoride (F) dentifrices with different F concentrations on bovine enamel. Enamel blocks (4.0 x 4.0 mm2, n=120) were selected according to their surface microhardness and divided into 12 groups. Slurries of dentifrices were used containing 0 (placebo), 275, 412, 550 and 1,100 ppm F (pH 4.5 or 7.0), as well as testing two commercial dentifrices (Crest, positive control, 1,100 ppm F and Colgate Baby, 500 ppm F). Enamel blocks were partially protected with an adhesive tape (control area) and then brushed by an automated toothbrushing machine (16,000 strokes). During this process, 0.4 ml of the slurries were injected every 2 mins on the enamel blocks. After toothbrushing, enamel wear was determined by profilometry. Results were analyzed by ANOVA and Tukey's test (p<0.05). The mean values for pH in the suspensions during treatment were 6.93, 4.32, 7.56 and 8.19 for neutral experimental dentifrices, acidic experimental dentifrices, Crest and Colgate baby, respectively. The abrasiveness of the acidic dentifrices was similar (p<0.05) to the neutral ones, whereas commercial dentifrices yielded lower abrasion (p<0.05). It was concluded that a reduction of the pH of dentifrices does not increase their abrasiveness.

Topical Oral Cavity Pharmacokinetic Modeling of a Stannous Fluoride Dentifrice: An Unusual Two Compartment Model

A pharmacokinetic model was developed describing the pharmacokinetics of stannous fluoride in human subjects after oral topical application of a stannous fluoride dentifrice. Twenty subjects participated in an investigation of an experimental dentifrice. Subjects rinsed their mouths with the experimental dentifrice slurry. Saliva and plaque samples were obtained from the subjects at various times up to 6 h after administration. Samples were analyzed for total tin content, used as an analytical marker for the active stannous fluoride ingredient, using a graphite furnace atomic absorption spectrometer. The modeling indicates that there is an obvious kinetic relationship between saliva and plaque compartments and that stannous fluoride is very well retained in and slowly released from plaque (and oral surfaces) into saliva. Additionally, both compartments are simultaneously loaded during administration unlike typical systemic drug behavior, and the elimination rate “constant” from the central compartment (saliva) changes due to changes in salivary flow. Stannous fluoride is cleared from saliva rapidly but very well retained in gingival plaque. The model with simultaneous loading of plaque and saliva describes these observations and may account for the prolonged antiplaque and antigingivitis benefits of stannous fluoride. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:3862–3870, 2009

Evaluation of the mechanical and chemical control of dental biofilm in patients with Down syndrome

To evaluate the mechanical and chemical control of dental biofilm in patients with Down syndrome, using different experimental dentifrices. Forty institutionalized children between ages 7 and 13 years in the mixed dentition phase participated in this study. An experimental cross-over, blind clinical trial was used, having the following protocols: fluoridated dentifrice (protocol G1); fluoridated dentifrice + chlorhexidine (protocol G2); fluoridated dentifrice + chlorhexidine + plaque-disclosing agent (protocol G3); and fluoridated dentifrice + plaque-disclosing agent (protocol G4). Each experimental stage lasted 10 days with a 15-day washout. The evaluated parameters were Plaque Index and gingival bleeding. The initial clinical conditions between each stage were similar. Statistical differences were observed (P < 0.001) for the clinical conditions evaluated before and after the treatments. The dentifrices containing plaque-disclosing agent, irrespective of their association with chlorhexidine, produced a greater reduction in the final plaque index. As for gingival bleeding, the dentifrice containing erythrosine and the one containing chlorhexidine produced similar results. The dentifrice containing an association of chlorhexidine and erythrosine gave the best results. With the methodology employed, it was possible to conclude that the combination of drugs (chlorhexidine, fluorine and erythrosine) within one dentifrice can be useful in controlling dental biofilm and in the reduction of gingival bleeding.

In vitro and clinical evaluation of specific dentifrices for complete denture hygiene

To study the physical properties of two experimental dentifrices for complete denture hygiene, their effect on denture biofilm removal and antimicrobial properties by means of a clinical trial. The experimental dentifrices comprised two compositions. One was based on the addition of 1% chloramine T (D1) and the other on the presence of 0.01% fluorosurfactant (D2). Measurements of density, pH, consistency, rheological features and abrasiveness were conducted. Sixty complete denture wearers were randomly assigned to three groups and were instructed to brush their dentures with a specific toothbrush: (1) Water (control); (2) D1; or (3) D2. Each method was used for 21 days. Denture biofilm was disclosed by a 1% neutral red solution and quantified by means of digital photos taken from the internal surface. Microbiological assessment was conducted to quantify Candida sp. and mutans streptococci. Data were evaluated by one-way anova and Tukey HSD, or Kruskal-Wallis (alpha = 0.05). Both dentifrices decreased biofilm coverage when compared with the control group. D1 was the most efficacious treatment to reduce mutans streptococci, whereas D2 showed an intermediate outcome (ANOVA, p < 0.040). No treatment influenced Candida albicans or non-albicans species (Kruskal-Wallis, p = 0.163 and 0.746, respectively). It can be concluded that brushing complete dentures with the experimental dentifrices tested could be effective for the removal of denture biofilm.

In vitro evaluation of the abrasiveness of a commercial low-abrasive dentifrice and an experimental dentifrice containing vegetable oil

Toothpastes usually contain detergents, humectants, water, colorant, fluoride and thickeners (e.g.: silica). Tooth wear has a multi-factorial etiology and the use of abrasive dentifrices is related to abrasion of dental tissues during toothbrushing. This study evaluated in vitro the abrasiveness of a commercial silica gel low-abrasive dentifrice compared to an experimental dentifrice containing vegetable (almond) oil. Distilled water served as a control group. Acrylic specimens (8 per group) were submitted to simulated toothbrushing with slurries of the commercial dentifrice, experimental dentifrice, almond oil and water in an automatic brushing machine programmed to 30,000 brush strokes for each specimen, which is equivalent to 2 years of manual toothbrushing. Thereafter, surface roughness (Ra) of the specimens was analyzed with a Surfcorder SE 1700 profilometer. Data were analyzed statistically by ANOVA and Tukey’s test at 5% significance level. There was no statistically significant difference (p>0.05) in the surface roughness after brushing with water, almond oil or experimental dentifrice. The commercial dentifrice produced rougher surfaces compared to the control and abrasive-free products (p<0.05). Further studies are necessary to confirm the potential benefits of using vegetable oil in toothpastes as an alternative to abrasives in an attempt to minimize the tooth wear caused by toothbrushing.

Abrasivity of a Dentifrice containing Nano Carbonate Apatite

Carbonate apatite has a similar structure to the inorganic component of teeth and bone. Although carbonate apatite is widely used as a bone substitute, there are no reports on its use as a desensitizing dentifrice. This in vitro study evaluated the relative abrasivity of the dentifrice containing nano-sized carbonated apatite (n-CAPs) using a Surface Profile Method (SPM). The dentin specimens were made from the root of extracted human molars. The cervical part of the teeth was sectioned with a diamond wheel disk. The teeth were embedded into an epoxy resin mold and the surface was gradually polished using silicone carbide paper. After grinding, the degree of surface roughness was examined within the range of 2 mm with tapping. The British Standard Institution reference dentifrice (BSI: CaCO3 40%) and the experimental dentifrices (group 1: n-CAPs 30%, group 2: n-CAPs 15% and silica 15%, group 3: n-CAPs 5% and silica 25%, group 4: silica 30%, group 5: CaCO3 10% and SrCl2 10%) were compared. The dentifrice slurries were prepared by mixing 24 grams of the dentifrice in 12 ml distilled water. Each tooth specimen was brushed 1,000 times with the dentifrice slurries using a back-and-forth stroke. The relative abrasivity of each dentifrice was evaluated by determining the ratio of the BSI standard dentifrice to each experiment. The results were analyzed using one-way ANOVA and Tukey’s multiple comparisons using Window SPSS (Statistical analysis system) 12.0. According to the results, Group 1 (3.2), which contained only n-CAPs appeared to have the lowest abrasivity than the BSI dentifrice (100). However, Groups 2 (124.2), 3 (137.9) and 4 (178.1), which contained n-CAPs and silica, appeared to have a higher abrasivity than the BSI dentifrice (p&gt;0.05). The relative abrasivity of group 5 (38), which was a commercial desensitizing dentifrice, was relatively lower. It appears that the higher abrasivity of the experimental is due to the shape and size of the silica component. Therefore, n-CAPs itself has no influence on the abrasivity of the dentifrice. The main reason for the low abrasivity of n-CAPs is believed to be its small particle size (range 50-90nm).

Low-Fluoride Dentifrices with Reduced pH: Fluoride Concentration in Whole Saliva and Bioavailability

This double-blind study assessed the fluoride (F) concentration in whole saliva and F bioavailability after the use of low-F dentifrices with reduced pH. Whole saliva was collected from 10 volunteers after brushing with: experimental dentifrices (pH 5.5) 275, 550 and 1,100 ppm F; commercial 500 ppm F, pH 6.9 and a ‘gold standard’ 1,100 ppm F, pH 6.5. To analyze F bioavailability, 9 volunteers ingested weights of four dentifrices equivalent to 2 mg F: 1,500 ppm F/MFP/CaCO₃, pH 9.5; 1,100 ppm F/NaF/silica, pH 5.5; 1,100 ppm F/NaF/silica, pH 7.0 and 1,100 ppm F/NaF/silica, pH 6.5 (‘gold standard’). Ductal saliva and urine were collected. F was analyzed by electrode. Data were tested using ANOVA and Tukey’s post hoc test (p < 0.05). The 550 ppm F/pH 5.5 dentifrice was similar to the ‘gold standard’ in its effect on whole saliva F concentration. The area under the curve of ductal saliva F concentration × time and urinary F excretion rates did not differ among the dentifrices. The results show that acidic low-F dentifrices are effective in increasing salivary F concentration and pH reduction does not seem to affect their F bioavailability.

Occlusion Effect of Dentinal Tubules of the Dentifrice Containing Nano-Sized Carbonate Apatite

Exposed dentine with patent tubules allows the movement of the tubule fluid leading to dentine sensitivity. An occlusion of patent dentinal tubules can effectively reduce the state of dentine hypersensitivity. Strontium chloride (SrCl2) has been known as a representative component of a desensitizing dentifrice. Recently, a desensitizing dentifrice containing nano-sized Carbonated Apatites (n-CAPs) was released onto the market. The aim of this in vitro study was to evaluate the occlusion effects of dentinal tubules in dentifrices containing several concentrations of the n-CAPs. One hundred human dentine specimens were embedded into a Teflon mold and ground with silicone carbide papers to expose the dentin surface. The dentin surface was etched with 37% phosphoric acid for 60 seconds and washed ultrasonically for 1 hour. The dentifrices were classified into five groups: experimental dentifrices Group 1: n-CAPs 5%, group 2: n-CAPs 15%, group 3: n- CAPs 0% and group 4: n-CAPs 30%, and the control dentifrice group 5: SrCl2 10%. The dentifrice slurries were prepared as 20 grams of dentifrice in 80 ml of distilled water. Fifty specimens were brushed with the dentifrice slurries using a V8 Cross Brushing Machine. Tooth brushing was performed 5,000 times using a back-and–forth stroke. Images showing the sizes of the dentinal tubules were taken by scanning electron microscopy (×3000) and the changes in the tubule sizes were analyzed using a digital analyzer. The n-CAPs used in this study had a high solubility and affinity to bone minerals. In addition, the n-CAPs were well deposited on patent dentinal tubules. The group 1 dentifrice (n-CAPs 5% and silica 25%) showed the highest dentinal tubule occlusion, and there was a statistically significant difference between group 4 and the control (p&lt;0.05). Overall, the dentifrice containing 5% nano carbonated apatite and 25% silica is the most effective in occluding dentinal tubules.

Abrasivity of Desensitizing Dentifrice Containing Sodium Metasilicate

This in vitro study compared the abrasivity of commercial desensitizing dentifrices with a sodium metasilicate (Na2SiO3) dentifrice using a Surface Profile Method. Dentin specimens were made from the root of extracted human molars. The cervical part of the teeth was sectioned with a diamond wheel disk. The teeth were embedded into an epoxy resin mold and the surface was gradually polished by silicone carbide paper. After grinding, the degree of surface roughness was tested within the range of 2 mm with tapping. The British Standard Institution reference dentifrice (BSI: CaCO3 40%) and experimental dentifrices (group 1: Na2SiO3 25%, CaCO3 10% and SiO2 10%, group 2: CaCO3 10% and SiO2 10%, group 3: CaCO3 10% and SrCl2 10%, group 4: Colloidal Silica 2-3% and Hydroxyapatite 10-20%) were evaluated. The dentifrice slurries were prepared by mixing 24 grams of the dentifrice in 12 ml distilled water. Each tooth specimen was brushed with the dentifrice slurries 1,000 times. The relative abrasivity of each dentifrice was evaluated from the ratio of the BSI standard dentifrice to each experiment. The results were analyzed by one-way ANOVA and Tukey’s multiple comparisons using Window SPSS (Statistical analysis system) 12.0. Groups 1 (71), 2 (74.2), 3 (38) and 4 (7.8) showed a lower abrasivity than the BSI dentifrice (100) (p&lt;0.05). The relative abrasivity of groups 3 (38) and 4 (7.8) was the lowest compared with the BSI dentifrice (100). However, group 1 (71) containing Na2SiO3 showed a similar abrasivity to group 2 (74.2), which did not contain Na2SiO3 (p&gt;0.05). Therefore, Na2SiO3 had no influence on the abrasivity of the dentifrice. In conclusion, the dentifrice containing Na2SiO3 had a lower abrasivity than the BSI reference dentifrice, but showed a significantly higher abrasivity than the existing commercial desensitizing dentifrices. Overall, the relatively high abrasivity of Na2SiO3 dentifrice is believed to be the result of other components in the abrasive system.

An Anticalculus Dentifrice with Sodium Hexametaphosphate and Stannous Fluoride: A Six-month Study of Efficacy

To compare the anticalculus efficacy of an experimental dentifrice (0.454% stabilized stannous fluoride/sodium hexametaphosphate) with a negative control. This was a randomized, examiner-blind, parallel group study. After a three-month run-in, qualifying subjects were randomized to the experimental or control dentifrice to use twice a day for six months. Volpe-Manhold Index (V-MI) and oral soft tissue examinations were conducted at baseline, three, and six months. Additional analyses were performed separately at three and six months on three subgroups categorized into high, medium, and low calculus-forming subjects. Compared to the control group, the experimental dentifrice group had a mean calculus score statistically significantly lower at both three months (50%) and six months (55%) post-treatment (p<0.001). Compared to control scores, mean experimental dentifrice calculus scores at three and six months were statistically significantly lower at both points in time for high, medium, and low calculus forming sub-groups (p<0.001). Both products were generally well tolerated. The experimental dentifrice revealed significant anticalculus efficacy compared to the control regardless of levels of baseline calculus formation. The stannous fluoride/sodium hexametaphosphate dentifrice technology is an effective calculus inhibitor for home care.

In situ effect of a dentifrice with low fluoride concentration and low pH on enamel remineralization and fluoride uptake

Since the anticaries effect of a dentifrice with low fluoride concentration and low pH is unknown, the aim of the present study was to evaluate in situ the enamel remineralizing ability of this type of formulation. A double-blind crossover design employing 3 phases of 45 days was conducted. Six adult volunteers wore palatal devices containing 6 previously demineralized human dental enamel slabs, which were subjected 3 times a day to one of the following treatments: non-fluoridated dentifrice (negative control); dentifrice containing 1, 100 microg F/g, pH 7.0 (positive control); dentifrice containing 550 microg F/g, pH 5.5 (experimental). At the end of each phase, enamel remineralization was assessed in terms of cross-sectional microhardness, and loosely as well as firmly bound fluoride formation was determined on the enamel surface. Fluoridated dentifrices were more effective than the negative control in forming loosely and firmly bound fluoride on enamel (P < 0.05). However, the positive control formed more loosely bound fluoride than the other treatments (P < 0.05). Microhardness analysis showed that the fluoridated dentifrices were more effective than the negative control (P < 0.05) in remineralizing dental enamel, although no statistically significant difference was observed between them. Thus, the experimental dentifrice was shown to be effective in remineralizing dental enamel, and this may be attributable to its ability to form firmly bound fluoride on enamel.

The effect of a triclosan/copolymer/fluoride liquid dentifrice on interproximal enamel remineralization and fluoride uptake

The authors measured the enamel remineralization of dental interproximal surfaces by a triclosan/copolymer/fluoride liquid dentifrice to test its performance against that of a standard toothpaste. In a randomized, crossover, blinded, in situ protocol, the authors fitted 19 healthy adult subjects with mandibular appliances holding bilateral, interproximal bovine enamel slabs. They measured initial abrasion levels and fluoride content. In a two-phase crossover protocol, they evaluated the percentage of surface mineral recovery, or SMR, and fluoride uptake caused by the experimental dentifrice and a fluoride-containing traditional control toothpaste. Abrasion depths were similar and not different statistically (P > .05). The interproximal blocks exposed to the triclosan-containing liquid dentifrice had a mean fluoride uptake that was nearly 100 parts per million (13.1 percent) greater than that achieved with the American Dental Association-accepted control dentifrice. This finding, while not statistically significant, may indicate enhanced performance of the experimental dentifrice because the initial enamel slab abrasion depths were shown to be quite uniform. Moreover, the blocks exposed to the experimental toothpaste had a 49.8 percent SMR, while the positive control blocks had an SMR of only 36.9 percent. This enhanced remineralization performance was statistically significant (P < .05). This is the first study to show enhanced performance of a triclosan-containing liquid dentifrice in preventing interproximal dental caries. The difference in percentage of SMR was statistically significant and is likely to be clinically relevant. The results of this preliminary study offer evidence supporting clinicians' recommendation of the new liquid dentifrice to patients who are prone to developing interproximal carious lesions.

Toothbrushing with vegetable oil: a clinical and laboratorial analysis.

The dentifrices currently available in the marketplace contain many anticariogenic substances, fluoride and abrasives aimed to better clean the dental surface, remove dental plaque, improve salivary flow and its buffer capacity and reduce colonies of bacteria such as S. mutans, the causative agent of dental caries. The objective of this study was to evaluate the possibility of adequately removing dental plaque using an experimental almond oil dentifrice (Titoil) with no abrasives or antiplaque agents. This study was carried out with 80 volunteers, all of them 18-year-old recruits from the military training school of Araçatuba -- SP. Saliva sampling and dental plaque disclosing were undertaken both before and after 28 days of toothbrushing with a low abrasive dentifrice (Group 1: 40 volunteers) or with Titoil (Group 2: 40 volunteers). Statistical analysis of the results revealed that the experimental dentifrice (Titoil) did not interfere with salivary flow and reduced dental plaque more than the low abrasive dentifrice, improved the salivary buffer capacity and decreased salivary S. mutans (Caritest-SM) as much as regular dentifrices. It was concluded that if the dental industry replaces abrasive by vegetable oil in dentifrices, these will be more effective in maintaining oral health and will cause less dental abrasion.