Relative Dentine Abrasivity Research Articles

Interpretation of the effect of using whitening toothpastes through a literature review

Advertising and marketing play a crucial role in the perception of the effectiveness of whitening toothpastes. The study's aim was to interpret the effect of using whitening toothpastes through a literature review. This study adopted a hermeneutic perspective to interpret the collected data. The implemented methodology was observational, descriptive, cross-sectional, and retrospective. A search was conducted in the PubMed and Google Scholar databases in English, as well as SciELO, Scopus, and Elsevier in Spanish, using key terms in both languages. Ultimately, 25 articles offering valuable and relevant information for the study were analyzed. The study revealed that whitening toothpastes, specifically Colgate Maxwhite, Colgate Luminous White, and Crest with peroxide, stand out for their ability to significantly improve color and provide an effective polish to the dental surface, compared to other brands that do not achieve these results. Additionally, the importance of selecting toothpastes with a Relative Dentin Abrasivity (RDA) index of less than 250 to prevent dental sensitivity and enamel damage is emphasized. Although no significant differences were found in the enamel's microhardness among the pastes evaluated, Crest appears to offer superior resistance on the external surface of the dental tissue. The study's major conclusion underscores the need for an informed choice of whitening toothpastes, prioritizing those with evidence of efficacy in improving dental color and maintaining a low abrasivity index to protect dental health

Influence of abrasive dentifrices on polymeric reconstructive material properties after simulated toothbrushing

To assess the influence of dentifrices with different abrasiveness levels on the properties of dental reconstructive materials. Forty-eight cylinders were obtained from four polymeric materials, being two CAD/CAM acrylic resins (Ivotion-Dent and Ivotion-Base), one injected acrylic resin (IvoBase-Hydrid) and one light-cured resin composite (Empress Direct). Specimens were allocated to four subgroups for toothbrushing simulation according to the dentifrice relative dentin abrasivity (RDA) and silica content: (i) RDA 0 = 0%; (ii) RDA 50 = 3%; (iii) RDA 100 = 10%; and (iv) RDA 120 = 25%. Specimens were then subjected to toothbrushing. Surface analyses [surface roughness Ra (SR) and scanning electron microscopy (SEM)] along with hardness and optical properties [translucency parameter (TP) and contrast ratio (CR)] were evaluated before and after toothbrushing. Statistical analyses were performed using ANOVA and Tukey test. A significant increase in SR was observed after toothbrushing with higher RDA toothpastes for Ivotion-Dent (100 and 120) and IvoBase-Hybrid (120). Ivotion-Base and Empress Direct presented no significant differences in SR when analyzed as a function of timepoint and RDA levels. Hardness was not influenced by toothbrushing with different RDA dentifrices, except for Empress Direct with RDA 0 toothpaste, where a decrease in the hardness was observed. TP of Ivotion-Dent and Empress Direct significantly decreased after toothbrushing with higher RDA dentifrices and CR of Ivotion-Dent, Empress Direct and IvoBase-Hybrid significantly increased with higher RDA dentifrices. The levels of dentifrice abrasiveness affected differently the SR, hardness and optical properties of polymeric reconstructive materials after toothbrushing.

Longevity of extrinsic stains on monolithic zirconia restorations: An in vitro study

Three-mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) has been commonly used for fixed prosthodontic restorations. The opacity of 3Y-TZP may be masked with external staining, although the longevity of extrinsic stains applied to monolithic zirconia is unclear. The purpose of this in vitro study was to analyze the color and surface roughness of extrinsically stained zirconia specimens after thermocycling and toothbrushing. Monolithic Ø12.5×1.25-mm zirconia disks were milled from 3Y-TZP blocks, sintered according to manufacturer instructions, and then divided into 3 groups (C, J, and O; n=16) for application of stain and glaze. All specimens underwent 10 000 thermocycles in distilled water before being further divided into 2 dentifrice groups (n=8): normal grit, low relative dentin abrasivity (RDA) (Subgroup N) and abrasive grit, high RDA (Subgroup A). Specimens were brushed in a multistation brushing machine under 1.47N of force using a 5:8 toothpaste and distilled water slurry for 10 000 cycles with a straight (American Dental Association Standard) toothbrush to simulate 1 year of toothbrushing. Color and surface roughness measurements were obtained at 3 time points: baseline, after thermocycling, and after brushing. A 2-way repeated measures ANOVA was used to independently assess changes in color and surface roughness with respect to thermocycling and brushing (α=.05). Group J displayed no significant change in color for either dentifrice system (P>.05). However, a significant change in surface roughness was observed for both dentifrice subgroups (P<.001). Group C specimens displayed significant changes in color (P<.001) and surface roughness (P<.001) for both dentifrice systems. Group O specimens displayed significant changes in color (P<.025) for both dentifrice systems and significant changes in surface roughness (P<.004) for subgroup A, but no significant changes for subgroup N (P=.075). Artificial aging of monolithic zirconia resulted in changes in color and surface roughness that did not surpass the thresholds for perceptibility and acceptability. This study failed to establish durability limits for extrinsic stains applied to 3Y-TZP.

Effect of staining and whitening systems on color stability of computer aided design/computer aided manufacturing lithium disilicate glass ceramic

PurposeTo investigate the effect of coffee stain and whitening systems on the color stability of CAD/CAM glazed lithium disilicate glass-ceramics (LDGCs). Methods68 glazed LDGC discs (12 × 10 × 2 mm) were fabricated using blocks of CAD/CAM systems(IPS e.max CAD ceramic). Baseline color was measured (CIE/L*a*b*), and specimens were randomized into four groups (n = 17). All specimens were stained (coffee solution; 24 h/d × 12) and then subjected to two whitening protocols. G1- (kept moist × 7 days); G2-positive control (brushed with distilled water, 200gm/load, 2 min twice daily × 7 days); G3- whitening toothpaste (Colgate optic white; relative dentinabrasivity = 100, 200gm/load, 2 min twice daily × 7 days) and G4-simulated at-home bleaching protocol (Opalescence,15% carbamide peroxide (CP), 6 h/day × 7 days). The study outcome was color change (ΔE) measured at baseline, after staining, and after whitening treatments. Data were analyzed using paired T-test and one-way ANOVA (α = 0.05). ResultsAll groups stained equally (p > 0.05) but were not clinically significant (ΔE ≤ 1.05). Stains were significantly (p ≤ 0.01) improved in G2 and G3 (ΔE = 0.69 and 0.63), yet were not eliminated compared to bleaching, which had the highest color improvement and completely removed the stains (ΔE = 0.72). ConclusionsGlazed LDGC was color stable after simulating one year of coffee staining. Bleaching, using 15% CP for a week, completely removed the stains and returned the LDGCs to their original shade.However, simulating eight months of brushing, regardless of the toothpaste content, improved the color outcome but didn’t remove it completely.

Toothpaste Abrasion and Abrasive Particle Content: Correlating High-Resolution Profilometric Analysis with Relative Dentin Abrasivity (RDA).

In this in vitro study, the influence of the concentration of abrasive particles on the abrasivity of toothpastes was investigated using laser scan profilometry on polymethyl methacrylate (PMMA) surfaces with the aim of providing an alternative method to developers for screening of new toothpaste formulations. PMMA plates were tested in a toothbrush simulator with distilled water and four model toothpastes with increasing content of hydrated silica (2.5, 5.0, 7.5, 10.0 wt%). The viscosity of the model toothpaste formulations was kept constant by means of varying the content of sodium carboxymethyl cellulose and water. The brushed surfaces were evaluated using laser scan profilometry at micrometer-scale resolutions, and the total volume of the introduced scratches was calculated along with the roughness parameters Ra, Rz and Rv. RDA measurements commissioned for the same toothpaste formulations were used to analyze the correlation between results obtained with the different methods. The same experimental procedure was applied to five commercially available toothpastes, and the results were evaluated against our model system. In addition, we characterize abrasive hydrated silica and discuss their effects on PMMA-sample surfaces. The results show that the abrasiveness of a model toothpaste increases with the weight percentage of hydrated silica. Increasing roughness parameter and volume loss values show good correlation with the likewise increasing corresponding RDA values for all model toothpastes, as well as commercial toothpastes without ingredients that can damage the used substrate PMMA. From our results, we deduce an abrasion classification that corresponds to the RDA classification established for marketed toothpastes.

Abrasive Enamel and Dentin Wear Resulting from Brushing with Toothpastes with Highly Discrepant Relative Enamel Abrasivity (REA) and Relative Dentin Abrasivity (RDA) Values.

To investigate the absolute wear caused by toothpastes with highly discrepant REA (Relative Enamel Abrasivity) and RDA (Relative Dentin Abrasivity) values on both enamel and dentin: Candida Peppermint (CP; REA: 1; RDA: 42), Colgate Total Original (CTO; REA: 4; RDA: 100), Signal White System (SWS; REA: 8; RDA: 143), and Candida White Diamond (CWD; REA 244; RDA: 12). Eighty (80) bovine enamel samples and 80 dentin samples were divided into four groups each (n = 20) and investigated after a 6-h brushing procedure (21,600 cycles, 60 cycles/min, load of 2.5 N) with the four toothpastes. The abrasive enamel and dentin wear were registered using a contact profilometer. The median and interquartile range (IQR) of the abrasive enamel and dentin wear were calculated for each group. Pairwise comparisons were conducted using the Wilcoxon signed-rank exact test, and the p-value was adjusted according to Holm (statistical significance set at 0.05). CWD led to the highest abrasive enamel wear (9.86 μm [5.77]). CTO caused the highest abrasive dentin wear (166.70 μm [69.90]), being statistically significantly higher than the wear for CP (54.20 μm [24.00]) and CWD (17.00 μm [7.80]) (p = 0.00001). The abrasive dentin wear for CWD was statistically significantly lower in comparison to all other groups (p = 0.00001). Toothpastes with highly discrepant REA and RDA values presented statistically significantly different absolute wear on enamel and dentin. REA and RDA values should both be declared for every toothpaste.

Relative dentin and enamel abrasivity of charcoal toothpastes.

Very little data are known about charcoal toothpastes. The aim of this study was to counteract the missing data by determining the relative dentin abrasivity (RDA) and relative enamel abrasivity (REA) values of charcoal toothpastes. Radioactively charged dentin and enamel samples were randomly divided into groups of eight specimens. Each group was brushed with two of total 12 charcoal toothpaste slurries and with a standard abrasive with a known RDA and REA value. The measured radioactivity in counts per minute within the slurries corresponds to the amount of dentin or enamel abraded. RDA and REA values of the charcoal toothpastes were expressed relative to the known value of the standard slurry. The RDA and REA values of the charcoal toothpastes have a broad range of 24-166 and 0-14, respectively. The RDA and REA values do not differ significantly from previously tested commercially available toothpastes. However, the lack of fluoride compounds in many of the investigated charcoal toothpastes can have a less beneficial effect for the consumers. It is very important to educate patients accordingly.

Clinical study of the toothpaste for the treatment of dental hypersensitivity

BACKGROUND: Given the increasing number of local and general factors in the development of hyperesthesia symptoms, the problem of the prevention and treatment of dental hypersensitivity is becoming increasingly urgent.&#x0D; AIM: To evaluate the clinical efficacy of toothpaste with low abrasiveness (relative dentin abrasivity 35) fluorides for sensitive teeth.&#x0D; MATERIAL AND METHODS: Thirty-five patients were diagnosed with hyperesthesia of the hard tissues of the teeth. Patients used the proposed toothpaste containing RDA 35, aminofluoride, and sodium fluoride. Hyperesthesia was determined before brushing, immediately after brushing, after 1 week, and after 1 month of using the studied toothpaste. Hyperesthesia was determined using a stream of air (Schiff test) and irritation with a dental probe (WongBecker scale).&#x0D; RESULTS: After 1 month of using the toothpaste, 97.1% (n=34) of the patients showed a decrease in dental sensitivity according to the Schiff test and 100% (35) according to the WongBecker scale.&#x0D; CONCLUSION: The presented toothpaste helps reduce hyperesthesia of hard dental tissues in 100% of cases within a month of its use.

Effect of Toothpaste on the Surface Roughness of the Resin-Contained CAD/CAM Dental Materials: A Systematic Review.

Background: The purpose of this review is to describe the possible effect of toothbrushing on surface roughness of resin-contained CAD/CAM materials. Methods: Systematic literature search for articles published in peer-reviewed journals between January 2000 and February 2020 has been conducted, which evaluated the effect of brushing on surface roughness of resin-contained CAD/CAM dental materials. The research was conducted in Scopus, PubMed/Medline, Web of Science, Embase, and Science Direct using a combination of the following MeSH/Emtree terms: “brushing”, “resin-based”, “dental”, “CAD/CAM”, and “surface roughness”. Results: A total of 249 articles were found in the search during initial screening. Fifty-five articles were selected for the full-text evaluation after the steps of reading of abstract/title and remotion of duplicate. Only six articles fulfilled the inclusion criteria. The Cohen’s Kappa agreement test showed an index of 0.91 for full-text. Discussion: Four of five selected articles identified an increase of surface roughness on resin-contained CAD/CAM materials after toothbrushing. Although all the articles examined used different toothpastes with no homogeneous relative dentine abrasivity (RDA) and cycles of brushing, the findings are about the same. The possible reason is attributable to the compositions of the resin-contained CAD/CAM materials. Conclusions: The surface roughness of most resin-contained CAD/CAM materials was affected by artificial toothbrushing. Correct knowledge of the composition of the dental material and toothpastes is fundamental to avoid an increase of surface roughness on prosthetic rehabilitation.

Effect of Enamel Pretreatment with Pastes Presenting Different Relative Dentin Abrasivity (RDA) Values on Orthodontic Bracket Bonding Efficacy of Microfilled Composite Resin: In Vitro Investigation and Randomized Clinical Trial.

Bonding failure is a clinical issue frequently encountered in orthodontic practice. The aim of this study was to evaluate enamel pretreatment both in vitro and clinically using agents with different RDA values before brackets’ bonding, to assess if RDA can affect the Shear Bond Strength (SBS), Adhesive Remnant Index (ARI) and clinical failure rate of orthodontic brackets. For the in vitro study, 220 bovine teeth were pretreated with agents with different RDA values. Subsequently, brackets were bonded. For the clinical study, 20 patients underwent bonding of 20 brackets each with a split-mouth design. Low and high RDA toothpastes were used for enamel pretreatment. SBS, ARI and failures were recorded. Higher SBS values were found for teeth pretreated with lower RDA agents; conversely, lower SBS values were found for teeth pretreated with higher RDA agents (p < 0.05). For high ARI values, RDA increased too (p > 0.05). In the clinical study, a significantly lower failure rate was reported for teeth pretreated with low RDA toothpaste (2.5% in low RDA group, 7.0% in high RDA group; p < 0.05). No significant differences were assessed comparing the two dental arches and anterior and posterior sites. Enamel pretreatment with low RDA toothpastes could increase brackets’ survival rate. Further in vitro and clinical studies would be welcomed to confirm these findings.

Impact of Brushing Protocols on Dentin Abrasion Caused by Different Abrasive Slurries.

To determine the impact of the brushing protocol on dentin wear by comparing continuous to intermittent brushing, with the same total time of brushing. Dentin specimens (n = 120) were evently distributed into six groups (A-F). The samples were brushed with slurries of different relative dentin abrasivity (RDA): Groups A+B (Sident 2480-1; RDA 85), groups C+D (Zeodent 113; RDA 67), and groups E+F (Zeodent 103; RDA 174). Groups A+C+E were brushed continuously (25 min) with one slurry preparation, while groups B+D+F were brushed intermittently (25 x 1 min) with a renewal of the slurry after each sequence. Dentin wear was determined using surface profilometry and statistically analysed with ANOVA and post-hoc tests. Neither the mode of brushing (p = 0.72) nor the interaction (p = 0.18) of the brushing mode with the type of abrasive particles had a significant influence on the abrasive dentin wear. Only the type of abrasive particles had a statistically significant influence on abrasive dentin wear (p < 0.001). The mode of brushing (continuously or intermittently) has no influence on abrasive dentin wear.

In situ evaluation of desensitizing toothpastes for protecting against erosive tooth wear and its characterization

This five-phase, single-blind, crossover in situ trial evaluated the effects of desensitizing or anti-erosive toothpastes on dentin erosive wear and tubule occlusion. Some characteristics such as relative dentin abrasivity (RDA), viscosity (V), cytotoxicity, and fluoride and calcium (Ca) availability of the toothpastes were also tested. Samples were positioned on removable intraoral appliances from 15 volunteers (n=4), according to the groups, C-control (0 ppm fluoride), F-sodium monofluorophosphate (MFP), A-MFP and arginine+calcium carbonate, CSP-calcium sodium phosphosilicate, and CS-MFP and calcium silicate+sodium phosphate. Erosion-abrasion cycling was performed (1% citric acid, 2min, 6×/day; toothbrushing, 5s, 2×/day). Surface loss (SL) was evaluated by optical profilometry. Environmental scanning electron microscopy images (ESEM) counted the number of open dentin tubules (ODTs). Data were statistically analyzed (α=0.05). There were no significant differences in SL among groups (p=0.468). The ODT for CSP, CS, and A groups were significantly lower than the control. CSP and CS presented significantly less ODT than F, but they did not significantly differ from A. F and CS were more abrasive than all the other toothpastes; CSP was more abrasive than A, and C was the least abrasive. CSP presented higher V (p<0.05). All toothpastes presented lower cell viability than the control without toothpaste exposure. F and A presented significantly higher values of F- (p<0.05). All fluoride toothpastes had similar amount of Ca, differing from the control (p<0.05). Although the toothpastes caused similar degree of erosive wear, CSP and CS were able to occlude the dentin tubules. Desensitizing toothpastes containing calcium, sodium, phosphate, and silicate could be a suitable option for treating dentin hypersensitivity.

Comparison of the abrasive effects of children's toothpaste on glass ionomer cement

To evaluate the effect of two different children's toothpaste on the surface properties of conventional glass ionomer cement (GIC), which is used in Atraumatic Restorative Treatment (ART) method. There were 3 groups and 10 glass ionomer cements in each group. The distribution was as follows: Group 1, Splat; Group 2, R.O.C.S.; Group 3, Control. A test aparatus made of steel with a screw design that allows the replacement of electric toothbrushes was designed to provide 2 N force. Brushing was carried out for each samples for duration of 2 min, twice a day, for seven days. One-way ANOVA for intergroup comparison and paired sample T tests for intragroup comparisons were used in statistical analysis, the significance level was p < 0.05. According to the results, no statistically significant difference was found between the baseline and 7th day roughness values within and between groups (p > 0.05). Although not statistically significant, as a percental increase in roughness was found in each group compared to the initial values. This amount of increase was found in Group 2, Group 1 and Group 3 as a descending order. The results were supported by scanning electron microscopy analysis. As a result of this study, child pastes that do not cause a statistically significant increase in roughness were found to be safe for daily use. When considering long-lasting restorations, low relative dentin abrasivity (RDA) value child pastes can be recommended as they will encourage brushing with both taste and smell compared to brushing with water.

A Qualitative and Quantitative Study on the Abrasivity of five Philippine-brand Toothpastes

Background. Relative Dentin Abrasivity (RDA), as set by ISO 11609, is a standardized measurement on the abrasiveness of toothpaste. There are no published RDA values for Philippine-brand toothpastes. This study evaluated the degree of abrasion of five Philippine-brand toothpastes. Objective. To compare qualitatively and quantitatively the abrasivity of five Philippine-brand toothpastes (Brands X, U, H, HN, G) to two foreign-brand toothpastes Brand C (RDA 68) and Brand P (RDA 150). Methods. Twenty-four bovine dentin samples were brushed with a slurry of each of the toothpaste using a toothbrushing machine. A profilometer, scanning electron microscope and a visual measuring scope were used to determine abrasivity through the before-and-after-brushing surface roughness. Results. Ranked based on the difference of the means for surface roughness, before-and-after brushing, in decreasing order of abrasivity are: Brands P, X, U, H, C, HN, and G. Using Dunn’s test-post hoc test for Kruskal-Wallis test at p ≤ 0.05, we showed that the abrasivity of Brands G, H, and HN were not significantly different from Brand C, and Brand X was not significantly different from Brand P. Brand U was significantly less abrasive than Brand P and significantly more abrasive than Brand C. Conclusion. Brands G, H, and HN can be considered as low-abrasive toothpastes, Brand X a high abrasive toothpaste, and with Brand U was unclear as to category. Findings from qualitative data support the quantitative data.

Comparative Evaluation of Surface Roughness of Resin- Modified Glass Ionomer and Glass Hybrid Restorative Materials Simulated by Tooth Brushing: An in-Vitro Study

Objective: To compare the effect of tooth brushing on surface roughness of Resin-Modified Glass Ionomer Cement (RMGIC; GC Gold label 2LC Light Cured Universal Restorative) and Glass Hybrid (GH; GC EQUIA SYSTEM- EQUIA Forte™ Fil and EQUIA Forte™ Coat) restorative material at 1- and 3-months interval simulated by tooth brushing . Material and Methods: RMGIC and GH material specimens (20 each) were prepared according to manufacturer instructions in 10 mm × 2 mm dimensions using a mylar strip. A specially designed toothbrush simulator was used along with Oral B Pro 2 2000N powered toothbrush and Colgate Total dentifrice (Colgate-Palmolive India limited; Relative dentin abrasivity - RDA: 70 - Low abrasive) to perform brushing strokes. Specimens were subjected to surface roughness analysis before and after simulated tooth brushing at baseline, 1, and 3 months. Results: The intragroup comparison was done using repeated-measures ANOVA. Intergroup comparisons were done using an independent sample t-test and General Linear Model (ANCOVA). Surface roughness increased from baseline through 3 months in both RMGIC and GH groups. The mean surface roughness in RMGIC group was significantly higher than GH group at baseline 1 and 3-months, respectively (p<0.001, <0.001, and <0.001). Interaction between group and baseline surface roughness was not significant (p=0.466). The estimated marginal means were significantly higher in RMGIC than GH group (p=0.008) . Conclusion: The surface roughness of both RMGIC and GH restorative increased from baseline to 1 month and 3 months after the simulated toothbrushing protocol. GH exhibited significantly lower surface roughness than RMGIC at all the tested intervals.

The Effects of a coffee beverage and whitening systems on surface roughness and gloss of CAD/CAM lithium disilicate glass ceramics.

To investigate the effects of a coffee beverage and two whitening systems on the surface roughness and gloss of glazed Lithium Disilicate Glass-Ceramics (LDGC) for computer-aided design/computer-aided manufacturing (CAD/CAM) systems. Sixty-eight LDGC disks (12 × 10 × 2 mm) were prepared from blocks of CAD/CAM systems (IPS e.max CAD ceramic). Baseline measurements for surface roughness (Ra) and gloss (GU) were taken using a 3-D optical profilometer and a glossmeter, respectively; then specimens were randomized into four groups (n = 17). All specimens were immersed in a coffee solution (24 h × 12 days) then subjected to two whitening systems. G1-negative control (kept moist × 7 days); G2-positive control (brushed with distilled water, 200 g/load, 2 min twice daily × 7 days); G3-whitening toothpaste (Colgate optic white; relative dentin abrasivity (RDA) = 100, 200 g/load, 2 min twice daily × 7 days); and G4-simulated at-home bleaching protocol (Opalescence,15% carbamide peroxide (CP), 6 h/day × 7 days). The study outcomes were measured at baseline and after the treatments. Data were analyzed using paired T-test and one-way ANOVA (α = 0.05). The mean surface roughness significantly increased (p ⩽ 0.002) for all groups after the designated treatment protocols. Among groups, the mean surface roughness of G2 and G3 were significantly higher (p ⩽ 0.001) (Ra: 0.51 and 0.57 μm, respectively) compared to the control group (Ra: 0.23 μm), and were not significantly different from G4 (Ra: 0.46 μm). Surface gloss decreased with no significant change within or among groups after treatment. All glazed LDGC had a significant increase in surface roughness after being subjected to simulated 1 year of coffee drinking and whitening systems (15% CP and whitening toothpaste), and the greatest change was associated with brushing (simulating 8 months). However, coffee beverages and whitening systems had no significant effect on the surface gloss.

Buffer Solution Reduces Acidic Toothpaste Abrasivity Measured in Standardized Tests

It has been speculated that the diluent used to test toothpaste abrasivity in standard tests may have an impact on their results, especially in the context of acidic toothpastes. This study tested whether an acidic toothpaste is indeed more abrasive than a neutral counterpart of otherwise identical composition, and whether this increased abrasivity is prevented by a buffered solution simulating saliva. Two experimental toothpastes of identical composition yet different pH (7.0 vs. 5.0) were prepared using standard ingredients. Subsequently, they were tested in standard absolute dentin abrasion and relative dentin abrasivity (RDA) experiments. To prepare slurries for these tests, deionized water as recommended by the International Organization for Standardization (ISO 11609:2017) was used, or a buffer solution containing bicarbonate and phosphate. The pH in these slurries was assessed and compared to the pH obtained in oral slurries of healthy individuals. Results showed that a significant (one-way ANOVA, p &amp;lt; 0.05) increase in mean absolute dentin abrasion and RDA values by 35 and 14%, respectively, was obtained when water was used as the diluent in conjunction with the acidic toothpaste as compared to the buffer solution. This was not the case with the neutral toothpaste. This result was explained by the finding that the buffer solution neutralized the pH in experimental slurries of the acidic toothpaste, while deionized water was unable to elevate the pH of the acidic toothpaste. That toothpaste was also neutralized in oral slurries. It was concluded that indeed the current ISO standard may result in a systematic overestimation of acidic toothpaste abrasivity.

RDA and REA Values of Commercially Available Toothpastes Utilising Diamond Powder and Traditional Abrasives.

To investigate whether toothpastes with diamond powder vs those with traditional abrasives abrade dentin and enamel differently and to determine the relative dentin abrasivity (RDA) and relative enamel abrasivity (REA) values of those toothpastes. Dentin and enamel samples of bovine permanent incisors were randomly allocated into groups of eight, brushed with 20 different toothpastes (three of which contained diamond powder) and analysed for their RDA and REA values. Toothpastes with diamond powder exhibit low RDA values but high REA values. Some RDA values exceeded the ones declared by the manufacturer. Diamond powder as an abrasive might have a mild action on dentin, but it is highly abrasive on enamel.

Effectiveness of Thymoquinone and Fluoridated Bioactive Glass/Nano-Oxide Contained Dentifrices on Abrasion and Dentine Tubules Occlusion: An Ex Vivo Study.

Objectives Dentin hypersensitivity (DH) is mainly due to the loss and replenishment of minerals from tooth structure, where the lost minerals can be rehabilitated with a biomimetic approach. The objectives were to determine the relative dentin abrasivity (RDA) of experimental (EXT) dentifrices and to determine the efficacy to occlude dentinal tubules. Materials and Methods Experimental dentifrices contained nano-fluoridated bioactive glass (n-FBG: 1.5 wt.% [EXT-A], 2.5 wt.% [EXT-B], and 3.5 wt.% [EXT-C]), nano-zinc oxide (n-ZnO), and thymoquinone as active agents. Bovine dentin blocks were subjected to brushing treatments as per groups, that is, distilled water; commercial dentifrice (control, CT); EXT toothpastes; and EXT-D without active agents. Samples were tested for three-dimensional (3D) abrasion analysis according to ISO-11609:2010 (International Organization for Standardization [ISO]). The roughness average (Ra), RDA, surface topography, and elemental compositions were investigated. Statistical Analysis One-way analysis of variance (ANOVA) with post-hoc Tukey’s and Tamhane’s test was performed for characterizations using Statistical Package for the Social Sciences (SPSS) version 21. The result was considered significant with p -value ≤ 0.05. Results Comparisons of Ra differed significantly between all groups with p < 0.05 except CT and EXT-A. The RDA values of EXT-A, EXT-B, and EXT-C were calculated as 74.04, 84.26, and 116.24, respectively, which were well within the acceptable limit set by international standards. All n-FBG containing dentifrices demonstrated uniform occlusion of dentinal tubules; however, highly concentrated EXT dentifrices showed more occlusion. Conclusions Acceptable range of RDA and superior occlusion of tubules by novel dentifrices suggest that it may be recommended for treating DH.

In vitro abrasivity and chemical properties of charcoal-containing dentifrices

Objective Charcoal-containing dentifrices are gaining popularity, but scientific information on their effect on oral health is scarce. This study investigated properties of dentifrices that may affect dentine abrasivity, as well as their ability to adsorb fluoride, their pH and the presence of harmful substances. Materials and methods The dentifrices NAO and COCO were subjected to the following analyses: abrasivity, expressed as mean abraded depth and relative dentin abrasivity (RDA), and surface roughness of extracted human molars (n = 30) after simulated brushing; fluoride adsorption measured as concentration change; pH measurements; detection of polycyclic aromatic hydrocarbons by gas chromatography–mass spectrometry. The products were compared to a reference dentifrice (Colgate® MaxWhite), positive controls (ISO dentifrice slurry, activated charcoal for laboratory use) and a negative control (distilled water). Results The mean abraded depths of NAO and COCO were not different (p > .05), but higher than the reference dentifrice and the negative control (p < .05). The RDA values of NAO, COCO and the ISO dentifrice slurry were higher than the reference dentifrice value (p < .05) by up to 10 times. The dentine surface roughness was higher after brushing with NAO, COCO and ISO dentifrice slurry compared to distilled water (p < .05). No change in mean adsorbed fluoride concentration was observed after 24 h (p > .05). Both NAO and COCO were alkaline (pH > 7). Analysis of NAO revealed the presence of naphthalene (112.8 ± 2.0 ng/mL). Conclusion The charcoal-containing dentifrices were abrasive within acceptable limits set by ISO and did not adsorb fluoride. The presence of naphthalene in one product is a cause for concern.