Whitening Toothpaste Research Articles

Comparison the effect of charcoal-containing, hydrogen peroxide-containing, and abrasive whitening toothpastes on color stability of a resin composite; an in vitro study

BackgroundThis study aimed to compare the effects of charcoal-containing, hydrogen peroxide-containing, and abrasive whitening toothpastes on color stability of a resin composite.MethodsForty-five specimens were fabricated of spectrum TPH3 composite resin and stored in artificial saliva for 24 h. Baseline color assessment was performed using a spectrophotometer device. Then, the specimens were randomly assigned into 5 experimental groups, namely distilled water (GC), Bencer (GB), colgate optic white (GO), perfect white black (GP) and colgate total whitening (GT) toothpastes. The specimens immersed in coffee solution for 10 min and brushed for 1 min with respective toothpaste and then stored in artificial saliva until the next day. This cycle was repeated for 30 days. After 30 days, the final color assessment was performed using the spectrophotometer. Data were analyzed using one-way ANOVA and Tukey tests.ResultsExperimental groups were not significantly different in terms of Δa and ΔE values. However, ΔL and Δb values showed significant difference among the groups. Regarding Δa, GT and GC groups showed red color shift while the other groups showed green color shift. Regarding Δb, all groups showed blue color shift except GT group which showed yellow color shift.ConclusionNone of the whitening toothpastes could decrease discoloration caused by the coffee solution to the level below the perceptibility threshold except Colgate Optic White which reduced discoloration within the clinically acceptable perceptibility range.

The effect of optical brightening toothpaste on the color stability of esthetic restorative materials

Aim: The aim of this study is to evaluate the effects of whitening toothpaste applications on the color stability of different tooth-colored restorative materials (Fuji IX, GC Fuji II LC, Equia Forte, and Kerr Point 4) 
 Methodology: Standardized fourty disc-shaped specimens were prepared from esthetic restorative materials and polished. The baseline color values of each specimen were then measured using a spectrophotometer, according to the Commission Internationale de l'Eclairage L*, a*, and b* (CIELAB) color scale. Ten specimens from each group were then immersed in two different beverages (cherry juice and coke) for seven days. After immersion, the color value of each specimen was re-measured. Each sample was brushed with whitening toothpaste for 30 seconds using an electric toothbrush. The samples were kept in distilled water at room temperature and brushing continued twice a day for seven days. The color change value, Delta E (ΔE), was calculated. Data were analyzed by two-way ANOVA and post hoc Tukey's test.
 Results: When the results were evaluated, after the colored samples had been brushed with whitening toothpaste, a difference was found between the Delta E values according to the materials used (p<0.001), but no difference was found in relation to the beverages (p>0.001). When the values of the color changes were evaluated after the first brushing with whitening toothpaste and before the specimens were colored with drinks, a difference was observed in the Fuji II cola, Fuji II cherry, and Equia Forte cola groups (p<0.05). When the values of the color changes were evaluated for specimens in which brushing had been done twice a day for seven days with whitening toothpaste and before they were colored with drinks, a significant difference was observed in the Fuji II cherry and Equia Forte cola groups (p<0.05).
 Conclusion: Using Signal White Now whitening toothpaste for 2 min 2 times a day for seven days caused significant changes in the color of the restorative materials. The color change is dependent upon the type of restorative material that is used.
 
 How to cite this article: Kahvecioğlu F, Çoban E, Ülker HE. The effect of optical brightening toothpaste on the color stability of esthetic restorative materials. Int Dent Res 2021;11(Suppl.1):80-4. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.13
 
 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Color Change of Esthetic Restorative Materials for Different Staining and Whitening Dentifrices

Background: As the importance of the esthetic function of teeth increases, the use of esthetic restoration materials and whitening treatment are increasing. The purpose of this study was to investigate the color change of esthetic restoration materials upon using staining and whitening toothpaste. Methods: Light curing (LC) packable composite resin, LC flowable resin, LC glass ionomer (GI), and self-curing GI specimens were colored in coffee or curry for three hours a day for seven days. After that, regular toothpaste, whitening toothpaste containing hydrogen peroxide, and whitening toothpaste containing activated charcoal were applied for three minutes three times a day for two weeks. Luminosity (L), chromaticity a (a), and chromaticity b (b) were measured using a spectrophotometer once a week. Results: In the coffee-colored group, the change in L2*a2*b2 (E2) with time was significant (p=0.004), there was no difference for different toothpaste types (p=0.646), and there was significant difference (p＜0.001) for different esthetic restorative materials. The change of E2 in the curry-colored group was significant only for different esthetic restorative materials (p＜0.001). In the coffee-colored group, the L, a, and b values of the light-curing GI showed greater change than other materials after staining and one week after whitening, turning dark, red, and yellow. In the curry-colored group, L did not differ for different materials and times, and a and b showed the greatest difference in light-curing GI after staining and one and two weeks after whitening. Conclusion: The use of whitening toothpaste for two weeks was not different from the use of general toothpaste in the removal of staining or whitening. Since light-curing GI is the most vulnerable to coloration, it is recommended that coloring by food chromogen should be explained in advance, before using light-curing GI for teeth restoration.

Investigation of surface roughness values of various restorative materials after brushing with blue covarine containing whitening toothpaste by two different methods: AFM and profilometer.

The aim of this study is to evaluate the effect of whitening toothpaste on the surface roughness of resin-based restorative materials by different measurement methods. Twenty four specimens from each of human enamel, a microhybrid composite and two nanohybrid composites discs (8.0 diameter × 4.0 mm thick) were divided into two groups (n=12) according to toothbrushing solutıon and subjected to simulation toothbrushing (30,000 cycles) with both distilled water and whitening toothpaste containing blue covarine. Surface roughness was examined using atomic force microscopy (AFM), profilometer, and scanning electron microscopy (SEM), and the data obtained were subjected to analysis. Ra values of Tescera (TES) were significantly higher than Sonicfill 2 (SF2) when brushing both toothbrushing solutions for initial or 30,000 cycles. Roughness increased for SF2 and TES when brushed for 30,000 cycles and was higher than enamel and Herculite XRV Ultra (HXU). Human enamel was obtained lower surface roughness values brushed with toothpaste compared with distilled water. Evaluation of the surface roughness of control groups using the AFM revealed no statistically significant difference between the groups, but significant differences were found using a profilometer. The use of abrasive whitening toothpaste containing blue covarine and the number of brushing cycles affect the surface properties of human enamel and the restorative material, and also, the clinical success of the restoration. Toothbrushing for 30,000 cycles increased the surface roughness of all materials. The type of toothbrushing solution partially has affected surface roughness.

Colour stability of stained composite resins after brushing with whitening toothpaste.

The aim of this study was to evaluate the effect of brushing with whitening toothpaste on the colour change of composite resins discoloured with coffee. Disc-shaped samples were prepared using one nano-hybrid (Clearfil Majesty Esthetic), one micro-hybrid (GC G-aenial Anterior) and one nano-ceramic composite (Zenit) (n=6). After initial colour measurements, the samples were coloured in the coffee solution for 5days. Colour measurements were made again after the colouring process, and brushing simulation was applied for 7, 15 and 30days with two different whitening toothpastes containing calcium carbonate+perlite (Signal whitening system, SWN) and hydrated silica+hydrogen peroxide (Colgate optic White, COW) and a conventional non-whitening toothpaste containing hydrated silica (Sensodyne pronamel, SPN). Colour change (∆E00 ) after brushing was calculated using the CIEDE2000system. Repeated measures variance analysis was used for the analysis of data. G-aenial anterior and Zenit showed significant coloration compared to Majesty esthetic after coloration with coffee (p<0.05). The colour change in all composite resins was above the clinically acceptable limit (ΔE00 >1.8). Colour change over time after brushing with both whitening toothpastes differed significantly (p<0.05). SWN and COW exhibited a significantly higher whitening effect than SPN (p<0.05). While there was no significant difference in composite groups brushed with the SWS (p>0.05), there was a significant difference between Majesty esthetic, G-aenial anterior and Zenit in groups brushed with COW (p<0.05). Colour change was high in micro-hybrid and nano-ceramic composites which were discoloured in coffee. The whitening toothpastes were effective in reducing the coloration caused by coffee.

Whitening Efficacy of 3% Carbamide Peroxide Gel Activated by Lactoperoxidase.

Objective The aim of this clinical study was to evaluate the effectiveness of a whitening toothpaste containing 3% carbamide peroxide and lactoperoxidase. Materials and methods. Participants were instructed to brush their teeth using an enzymatic-activated dentifrice following a particular procedure for three weeks. Color was recorded before and after treatment using a VITA Easyshade spectrophotometer. Differences in L∗ (tooth color lightness), a∗ (displacement along the red-green axis), and b∗ (displacement along the yellow-blue axis) were measured before and after treatment using the paired t and the Wilcoxon signed-rank tests. Color changes (ΔE) were calculated using the obtained measurements. Results Thirty-four volunteers were included. ΔE was 4.03. For the set of 348 teeth, a greater tendency towards green (lower a∗) and blue (lower b∗) was observed (p < 0.05). There were no significant differences in lightness after treatment. Mandibular central incisors showed a greater tendency towards green (lower a∗) and blue (lower b∗). Bleaching effectiveness was observed in both the upper and lower central incisors and in the lateral mandibular incisors. Conclusion Based on these results, it may be concluded that brushing with an enzymatic-activated dentifrice is effective for whitening teeth.

Efficiency of activated charcoal powder in stain removal and effect on surface roughness compared to whitening toothpaste in resin composite: In vitro study

ObjectivesTo evaluate the efficacy of activated charcoal powder on extrinsic stain removal and its effect on surface roughness in stained resin composite in comparison with whitening toothpaste. Materials and methodsSixty-six disk-shaped composite specimens were fabricated using a custom-made ring mold. The specimens were stained using a coffee solution and stored in distilled water at 37 °C. The specimens were divided randomly into two groups, Group 1: Thirty-Three disks were subjected to brushing using whitening toothpaste (Control), and Group 2: Thirty-Three disks were subjected to brushing using charcoal powder. Specimens were evaluated for surface color and surface roughness at baseline after staining protocol and after the brushing process. ResultsChanges in color and surface roughness were highly significant (p < 0.0001) after brushing with activated charcoal powder and whitening toothpaste. However, no significant differences were found in color (p = 0.90) and surface roughness (p = 0.33) between the two bleaching techniques. ConclusionThe changes in the color and surface roughness of resin composite was significant after brushing with activated charcoal powder and whitening toothpaste. However, there were no significant differences between the two techniques.

Reduction of extrinsic tooth stain by a toothpaste containing 10% high cleaning silica, 0.5% sodium phytate and 0.5% sodium pyrophosphate: an 8-week randomised clinical trial

ObjectiveTo assess the effects for controlling extrinsic tooth stain of a whitening toothpaste containing 10% high cleaning silica, 0.5% sodium phytate and 0.5% sodium pyrophosphate, in comparison with a negative control toothpaste.MethodsA total of 86 adults who met with the inclusion and exclusion criteria were invited to take part in the study. They were distributed into test and control groups randomly. At baseline, 4 weeks and 8 weeks, the same examiner provided the clinical examinations, including evaluations of oral soft and hard tissues and measurements of tooth stain of the anterior teeth using the Lobene Stain Index. Adverse events and any changes in general health conditions of the patients were monitored.ResultsWhen the study was completed, comparisons between patients in test and control groups yielded statistically significant differences in Lobene stain adjusted mean area score [0.83 (0.05) vs. 1.13 (0.05)], Lobene stain adjusted mean intensity score [0.99 (0.06) vs. 1.32 (0.06)] and Lobene stain adjusted mean composite score [1.45 (0.13) vs. 2.50 (0.13)] (All, P < 0.001). Patients in the test group exhibited reductions of 26.55%, 25% and 42%, respectively in Lobene stain area, intensity and composite scores, relative to patients in the control group. Comparisons within groups showed that all three Lobene scores at 8 weeks in both groups were lower than those at baseline (All, P < 0.001).ConclusionThis study demonstrates that 8-week use of a toothpaste containing 10% high cleaning silica, 0.5% sodium phytate and 0.5% sodium pyrophosphate can effectively reduce extrinsic tooth stain.Trial registration NCT04238429 (before enrollment of the first participant). Data register: March 4, 2018.

Calcium Release from Different Toothpastes after the Incorporation of Tricalcium Phosphate and Amorphous Calcium Phosphate

This study aimed to investigate the free calcium released from different brands of toothpaste after incorporation with a beta-tricalcium phosphate (β-TCP)/amorphous calcium phosphate (ACP) mixed powder and with β-TCP powder alone. Four brands of toothpaste were used for the experiment: Nano-Bio Activation Toothpaste, Colgate Total Advanced Whitening Toothpaste, BORONIA Herbal Whitening, and BioMin F. The investigated β-TCP and ACP powders were prepared by a two-step sintering method using raw coral material. Analytical results found that the mean calcium concentration of the β-TCP/ACP (2:1) powder in deionized water was 3.4% when the pH was between 5 and 9. Moreover, statistical results revealed that the toothpaste containing β-TCP powder had significantly higher calcium concentrations than the normal toothpaste. The toothpaste containing mixed β-TCP/ACP powder had a higher calcium concentration than the toothpaste containing only β-TCP powder. Twice as much free calcium could be released from β-TCP/ACP toothpaste than from β-TCP-only toothpaste. Thus, toothpaste containing β-TCP/ACP mixed powder offers greater benefits to facilitate the remineralization of enamel than toothpaste containing only β-TCP.

Examining the effect of in vitro toothbrushing and the effect of different whitening toothpaste usages on the color change of a nanofilled composite

Examining the effect of in vitro toothbrushing and the effect of different whitening toothpaste usages on the color change of a nanofilled composite

Effect of whitening toothpastes containing activated charcoal, abrasive particles, or hydrogen peroxide on the color of aged microhybrid composite

This study aimed to assess the effect of different whitening toothpastes containing activated charcoal, abrasive particles or hydrogen peroxide on the color of aged microhybrid composite. In this in vitro, experimental study, 45 composite discs (2 mm × 7 mm) were fabricated of a microhybrid composite. They underwent accelerated artificial aging for 300 h, corresponding to 1 year of clinical service. The composites were then randomly divided into five groups (n = 9). One group served as the control and underwent tooth brushing with distilled water. The remaining four groups underwent tooth brushing with Colgate Total whitening (Gt), Colgate Optic White (Go), Perfect White Black (Gp) and Bencer (Gb) toothpastes in a brushing machine The International Commission on Illumination values (Lm, am, bm) were determined using a spectrophotometer. Color change (ΔE) calculated based on this formula: ΔEm= ([ΔLm] 2 + [Δam] 2 + [Δbm] 2)½. The differences were defined by ΔE1 (after aging-baseline),ΔE2 (after brushing-after aging) and ΔE3 (after brushing-base line). ΔE1 were evaluated to ensure that color mismatch had occurred (ΔE1 > 5.5). Difference in (L, a, b) parameters after aging and after tooth brushing in each group, color parameter changes (ΔL2, Δa2, Δb2, ΔL3, Δa3, Δb3) and ΔE2 and ΔE3 were analyzed and compared using Wilcoxon test and independent sample median test at P = 0.05 level of significance. The color parameter changes, ΔE3 and Δ E2 were not significantly different among the five groups (P > 0.05). In Gp and Gb charcoal a*, b*, and L* after tooth brushing (P < 0.05). In Colgate Optic group, the a* parameter significantly decreased while the L* parameter significantly increased (P < 0.05). The results showed that there is no significant difference in the color change of Spectrum composite following tooth brushing with different whitening toothpastes for two weeks. It should be noted that Δ E3 reached to <3.3 only in charcoal whitening toothpastes.

Effect of over-the-counter whitening strips and toothpaste on shear bond strength of orthodontic brackets.

BackgroundTo investigate: 1) the effects of over-the-counter white strip enamel bleaching and 2-Step whitening toothpaste application on the shear bond strength of orthodontic brackets at 24-hours and 7-days post-bleaching latent period; and 2) the correlation between amount of bleaching and shear bond strength. Material and MethodsSixty human premolar teeth were randomly assigned into two bleaching groups, white strip group treated with Crest® 3D WHITE™ LUXE Professional Effects Whitestrips (Proctor & Gamble, Greensboro, NC), and whitening toothpaste group, treated with Crest® 3D WHITE™ BRILLIANCE 2-Step Toothpaste (Proctor & Gamble, Greensboro, NC). The groups were further divided into 4 subgroups A, B, C, D (n=15 per group). Subgroups A and C were bonded 7 days after bleaching while subgoups B and D were bonded 24 hours after bleaching. Differences in shear bond strength between the subgroups and an unbleached control group (n=15) were compared using the Kruskal-Wallis test. Spectrophotometric color changes were recorded pre- and post-bleaching. ResultsThe mean shear bond strength for the white strip groups were 10.35±3.6 MPa and 11.69±4.33 MPa for the 7-day and 24-hour delayed bonding periods, respectively. Means for the whitening toothpaste groups were 11.01±4.31 MPa and 10.83±3.79 MPa for the 7-day and 24-hour delayed bonding periods. The mean for the control group was 9.59±3.32 MPa. There were no significant differences in shear bond strength between the groups at 7-days and 24-hour (P=0.650). There was a significant difference between teeth bleached with white strips as compared to those bleached with toothpaste and controls. The correlations between color change and shear bond strength were not significant (P=0.448). ConclusionsThere is a significant difference in the amount of whitening achieved by over-the-counter white strips compared to toothpaste; however, no significant effects on shear bond strength occurred after bleaching with white strips and toothpaste at 24-hours and 7-days. Key words:Bleaching, shear bond strength, orthodontics, over-the-counter.

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.

Abrasiveness and whitening effect of charcoal-containing whitening toothpastes in permanent teeth.

Charcoal toothpastes can whiten teeth through abrasion. The purpose of this study was to determine the level of whitening and abrasiveness of charcoal toothpastes in permanent teeth. In this in vitro study, 30 premolars were polished, sectioned, mounted, and stored for 5 days in a coffee solution at 37°C. The color and surface profile of the teeth were measured by spectrophotometry and a profilometric device, respectively. The specimens were divided into 3 groups of 10 and were brushed 2000 times (equivalent to 3 times a day for 1.5 months) in a brushing machine using 20 g of each toothpaste (Bencer, Beverly, and Colgate) mixed with 40 ml of distilled water. The color and surface profile were remeasured. Bonferroni test and repeated measures analysis of variance (ANOVA) were used to examine the abrasion. One-way ANOVA was used to assess the whitening. The three toothpastes caused changes in the surface profile (P = 0.0001). ΔE was equal to 3.3 (within the acceptable range) in all groups (95% confidence interval). There was no significant difference in abrasion (P > 0.05) and color change (P = 0.884) among toothpastes. The results of this study showed that all the three used toothpastes have the abrasive and whitening effect on the samples significantly. The differences between the toothpastes were not significant.

What to expect from whitening toothpaste?

To assess the whitening effect of whitening toothpastes, their ingredients were studied. These toothpastes turned out to have an influence articularly on the extrinsic discoloration of teeth caused by staining. To a large extent, the effectiveness of the whitening toothpastes relies on removing these extrinsic stains, preventing new stains from developing and on certain optical effects. The intrinsic colour of the teeth themselves is not, however, effected.

The composition of popular whitening toothpastes through the eyes of a chemist

The article presents the results of analysis of the composition of popular toothpastes for home teeth whitening. Chemical aspects of dentistry procedure of whitening teeth are considered, original authors schemes of ion-changes and oxidative process are given, which happen with it.

Effect of Actilux - Activated Whitening Toothpaste and Marine Salts on Color Change and Microhardness of Bovine Enamel

Purpose: To evaluate the effect of Actilux-activated whitening toothpaste and Marine salts powder on color change and microhardness of bovine enamel. Methods: Thirty intact bovine incisors were used in this study to produce enamel specimens. The specimens were randomly distributed into three groups (n= 10) according to the tested whitening agents as follows: Group I: BW; BlanX LED White Shock (Actilux-activated), Group II: MS; Marine salts whitening powder and Group III: CR; Crest regular fluoridated toothpaste. The specimens were stained using black tea solution for 5 days. Each specimen was brushed twice daily for 8 then 15 days. The color was assessed according to CIE (Lab) color system using a VITA Easyshade spectrophotometer. The microhardness was assessed using Digital Display Vickers Microhardness Tester at baseline, after staining, after 8 days, and 15 days brushing. Data were tabulated and statistically analyzed. Results: After 8 days brushing, BW showed the highest mean (ΔE) while MS and CR both showed lower mean (ΔE). BW and MS showed the highest mean (ΔE) after 15 days brushing with no statistically significant difference between them. After 15 days; BW showed the highest mean microhardness followed by MS while CR showed the lowest mean microhardness. Conclusion: Both Actilux-activated toothpaste combined with LED device and Marine salts powder were effective in tooth whitening as well as increasing enamel microhardness. The whitening efficacy and microhardness is time dependent.

Effect of Whitening Toothpastes and Brushing on Microhardness of Esthetic Restorative Materials.

Whitening toothpastes are widely used. Hence, it is important to understand their effect on the surface properties of restorative materials. To evaluate the effect of three over-the-counter whitening toothpastes and toothbrushing simulation on microhardness of three restorative materials. Forty cylindrical (10×2mm) specimens were prepared from each restorative material and randomly assigned into four groups/10 each according to the whitening toothpastes used and distilled water (control). All specimens were measured for microhardness (Baseline-T1). The specimens were brushed with a soft brush using an in vitro tooth-brushing simulator with the assigned whitening toothpaste using the same setting for brushing cycles/load for all groups. Specimens were then measured for microhardness (T2) similar to baseline. The highest (mean±SD) microhardness after application of the whitening toothpastes and brushing was recorded for Intense White and Filtek Z250 XT (127.6±1.8), followed by Optic White and Fuji ll LC (73.9±0.9) and Optic White and Photac Fill (72.7±1.3). There was statistically significant difference for microhardness between pre- and post-application of the whitening toothpastes and brushing for all tested restorative materials (P=0.0001). The microhardness of Filtek Z250XT with 3D White post-application of the whitening toothpastes and brushing was lowest compared to other toothpastes and control (P=0.0001). Microhardness increased after application of the whitening toothpastes and toothbrushing simulation for all combination of tested restorative materials and whitening toothpastes. The microhardness of FIiltek Z250XT with 3D White post-application of the whitening toothpastes and brushing was lowest compared to other toothpastes and control.

Effects of activated charcoal powder combined with toothpastes on enamel color change and surface properties.

To evaluate the effects of activated charcoal powder (COAL) combined with regular (RT) or whitening (WT) toothpastes on enamel color and surface in comparison to carbamide peroxide (CP). Dental blocks (n = 10/group) were randomly divided into COAL, COAL/RT, COAL/WT, CP, CP/RT, CP/WT, RT, WT, and CONT (without treatment). Simulated toothbrushing and whitening treatments were followed by colorimetric (ΔE00 , L*, a*, b*), surface roughness (Ra), and enamel topography assays. ΔE00 was submitted to two-way ANOVA and Tukey test. Color coordinates and Ra were tested with three-way repeated measures ANOVA (α = 5%). COAL exhibited greater ΔE00 than CONT (P = .048), but it did not enhance ΔE00 promoted by RT or WT (P > .05). COAL alone increased Ra (P < .001) and altered enamel topography. COAL did not increase Ra caused by RT and WT (P > .05). CP exhibited the highest ΔE00 (P < .05), but it raised Ra and changed enamel topography to a less extent than COAL. Even though charcoal powder did not increase enamel Ra when combined with toothpastes, the topography was negatively impacted by COAL. Also, COAL was unable to enhance the color change of RT and WT, or reach the effectiveness of CP. The use of activated charcoal-based product, claimed as a natural whitener, before brushing with toothpastes is not only ineffective to change the color of teeth, but also it might result in alterations on the enamel surface. Whitening with CP, instead, was effective during the same period of treatment, which still represents a more appropriate technique to whiten teeth.

Efficacy of whitening toothpaste containing blue covarine: A double‐blind controlled randomized clinical trial

This randomized clinical trial evaluated the efficacy and safety of a blue-covarine whitening toothpaste on tooth bleaching. Seventy-five subjects with shade mean C1 or darker were randomized into three groups (n = 25): CT-conventional toothpaste, WT-whitening toothpaste, and CP10-10% carbamide peroxide. Subjects from CT and WT brushed their teeth twice/day for 2 weeks. CP10 used bleaching gel for 4 hours/night for 2 weeks. Tooth shade and CIELab parameters were measured at baseline, after the first application, 2- and 4-week. ΔE*ab and ΔE00 were calculated. Subjects' perception about tooth color appearance, tooth sensitivity (TS), and gingival irritation (GI) were also assessed. At all evaluation periods, it was not observed differences between WT and CT considering tooth shade (P > 0.7) or CIELab parameters (P > 0.3). At 2- and 4-week, ΔE*ab and ΔE00 were higher for CP10 than WT or CT (P = 0.001). WT and CT reported major dissatisfaction with tooth color appearance than CP10 (P = 0.001). At 1- and 2-week, WT experienced GI and TS similar to CT, both lower than CP10 (P < 0.01). There were no significant differences in the whitening efficacy between whitening and conventional toothpastes. Neither of the dentifrices was as effective as at-home bleaching. The silica-based toothpaste containing blue covarine evaluated in this study did not give significant tooth whitening benefits over 2 weeks of use.