Whitening Dentifrice Research Articles

Effectiveness of Papain-Based Organic Dentifrices Versus Commercial Whitening Dentifrice on Tea-Induced Tooth Stains: An In Vitro Study.

Tooth discoloration is a common issue for oral health practitioners. Whitening treatments remove surface and deep stainsusing either chemicals or over-the-counter products. Due to harmful chemical effects, organic whitening products are increasingly preferred. This study compared the effectiveness of organic papain-based dentifrices (Perfora Magic Teeth Whitening Serum, Gurugram, India) on tea stains to commercially available Colgate whitening dentifrices (Colgate-Palmolive, New York, NY). Sixty maxillary central incisors for periodontal reasons were used and divided into two groups. Each sample was soaked in freshly brewed tea for 10 minutes daily and stored in artificial saliva (Nanochemazone, Kurukshetra, India) for 24 hours. After four weeks, group 1 was treated with papain-based dentifrices, and group 2 with Colgate Visible White teeth whitening paste(CVWP) daily for four weeks. Spectrophotometric analysis (VITA Easyshade V, VITA Zahnfabrik, Bad Säckingen, Germany) was performed pre-treatment and at four weeks post-treatment. Data were compiled and statistically analyzed. Compared with group 1, group 2 exhibited an optimal color change (ΔE). Statistically significant differences were observed between the mean ΔL (lightness) and Δb (blueness -b or yellowness +b) values. CVWP showed better color achievement and stain reduction due to abrasive and peroxide components. Although Perfora Teeth Whitening Serum has low efficacy in upgrading the color of the enamel surface, it is safe for long-term use.

Does the whitening dentifrice containing activated charcoal interfere with the properties of dental enamel? Microhardness, surface roughness and colorimetry analyzes.

The study evaluated the influence of whitening dentifrice containing activated charcoal on microhardness (MH), surface roughness (Ra) and colorimetry of tooth enamel. A total of 60 healthy bovine incisor teeth were used and divided into: G1 (regular non-whitening toothpaste), G2 (conventional whitening toothpaste), G3 (activated charcoal based whitening toothpaste) and G4 (10% carbamide peroxide gel - PC10). Groups G1, G2 and G3 underwent simulated toothbrushing for 14 days, while G4 received bleaching treatment for the same time. The readings of MH, Ra and colorimetry were performed before any intervention (T0 - baseline) and at the end of 14 days of the proposed treatments (T1). After confirming the normality of the data, the results of MH, Ra and colorimetry were subjected to 2-factor ANOVA for repeated measures (α = 5%). For MH, there were no statistical differences in G1, G2 and G3, only in G4. Considering Ra, a significant increase was observed in G2 and G3, with no statistical differences found in the other groups. Regarding colorimetry, the average color difference (ΔE) was greater in the G4 group (11.30 ± 4.31), even compared to the groups submitted to the whitening dentifrices: G2 (5.13 ± 2.75) and G3 (5.86 ± 3.66). It was concluded that the use of a whitening toothpaste containing activated charcoal caused deleterious effects on the enamel Ra, but did not affect the microhardness of the substrate, besides promoting a color change inferior to the regular non-bleaching toothpaste or PC10 gel. Key words:Whitening dentifrice, charcoal, roughness, microhardness.

Evaluation of Color Stability of Different Esthetic Restorative Materials with Whitening Dentifrices

Introduction: Color stability and surface roughness are important factors affecting the longevity of any restorative material, as a rough surface structure can lead to staining and discoloration. Aim: The aim of this study was to evaluate the effects of application of two over-the-counter whitening toothpastes (Colgate Optic White and Close-up) on the color stability of different esthetic restorative materials (resin composite and conventional glass-ionomer). Materials and Methods: Using Mylar strips, 120 specimens were created from each restorative material (resin composite and conventional glass-ionomer). Baseline color measurement was done. This was followed by brushing the specimens according to the groups were brushed with the different whitening toothpastes. Before measuring color, the samples were washed. Results: A significant color change was observed between the two restorative materials. The color change was significantly higher with Colgate Optic White than Close-up toothpaste. Furthermore, composite material showed higher color stability than glass-ionomer cement (GIC). Conclusion: When used for 2 min twice day for 15 days, the whitening toothpastes Colgate Optic White and Close UP do create noticeable changes in the color. Furthermore, composites showed higher favorability for color stability than GIC.

Evaluation of Color and Translucency of Stained and Glazed Monolithic Lithium Disilicates and Zirconia After Toothbrushing with Different Dentifrices and Thermocycling.

To evaluate changes in color and translucency of stained and glazed monolithic lithium disilicates and zirconia after toothbrushing with conventional or whitening dentifrices followed by thermocycling. Samples (n &#61; 20/material) from CAD/CAM (IPS e.max CAD [EC]) and pressable (IPS e.max Press [EP]) lithium disilicates and 5Y-PSZ zirconia (Prettau 4 Anterior [PA]) were prepared and received staining and glazing procedures. Aging was performed by toothbrushing with conventional (n &#61; 10) or whitening (n &#61; 10) dentifrices, followed by thermocycling simulating 5, 10, and 15 years. Color coordinates L*, a*, b*, , and C* and h° values were assessed with a spectrophotometer at baseline and after each aging period to calculate color changes (ΔE00), lightness (ΔL*), and translucency parameter (TP). Data were analyzed using three-way repeated measures ANOVA's followed by Sidak post-hoc test (α &#61; .05). When comparing the dentifrices, EC and EP produced the greatest ΔE00 after 15 years with the whitening dentifrice (P < .05). Regardless of the dentifrice, PA showed greater ΔE00 than EC after 10 years (P < .05). When comparing the aging periods, EC and PA did not show differences in ΔE00 for both dentifrices (P ≥ .05). EC and EP produced an increased ΔL* after 15 years in the whitening group (P < .05). In the whitening groups, the ΔL* values of PA differ (P < .005) from those of lithium disilicates. Regardless of the experimental group, the TP values followed the inequality: PA < EC < EP (P < .05). Overall, the color of stained and glazed monolithic lithium disilicates and zirconia changed under aging with greater effects for whitening dentifrice. Aging did not influence translucency.

Does the application of whitening dentifrices during at-home bleaching affect the bond strength of resin composite to dentin?

AimThis study aimed to evaluate the effect of using whitening dentifrices during at-home bleaching on the shear bond strength (SBS) of resin composite to dentin, and investigate whether the increased polymerization time would improve SBS.MethodsNinety-six bovine incisors were divided into 4 groups of 24, according to the whitening treatment applied as follows: group 1, at-home bleaching + brushing with a regular dentifrice; group 2, at-home bleaching + brushing with a whitening dentifrice containing ozone; group 3, at-home bleaching + brushing with a commercial whitening dentifrice; and group 4 (control), no whitening/brushing treatment. Each group was divided into two subgroups (n = 12) to assess the effect of curing time (20 versus 80 s) on SBS. A self-etch adhesive was bonded to dentin, and after 2-day water storage, SBS was determined.ResultsSBS was significantly affected by the whitening treatment (P = 0.03), but increasing the curing time had no significant effect on SBS (P = 0.137). Bond strength in group 1 was comparable to the control group (P > 0.05). The specimens in group 3 displayed significantly lower SBS than either group 4 or group 1 (P > 0.05). No significant difference was observed between the SBS of group 2 compared to any other group (P > 0.05). There was no significant association between the treatment group and failure type (P > 0.05).ConclusionThe bonding interface was not negatively influenced by the at-home bleaching procedure. However, using a commercial whitening dentifrice during at-home bleaching produced a significant detrimental effect on SBS. Extending the curing time would have no beneficial effect on adhesion to a whitened dental substrate.

Effect of Brushing Time with a Whitening Dentifrice on Surface Roughness of Anterior Composite ResinsRoughness of Anterior Composite Resi

Objectives: This study aimed to compare the surface roughness of three anterior composite resins with different filler size, rate, and shape after brushing for 5000, 10000, and 20000 cycles with a whitening dentifrice. Methods: 44 disk-shaped specimens of each material (5mm diameter, 2mm depth) G-aenial Anterior, Harmonize, Asteria were prepared and divided into four groups according to the brushing cycles (Initial, 5000, 10000, and 20000 cycles). Initial surface roughness values (Ra-values) were assessed using a profilometer and measurements were repeated after each brushing cycle. 4 specimens from each composite resin were observed by scanning electron microscopy before and after brushing. The data were analyzed by Shapiro Wilk., ANOVA, Tukey, Friedman, and Wilcoxon tests (p&lt;0.05). Results: The Ra-values of all groups increased in proportion to the number of brushing cycles (p&lt;.05). The Ra-values of both Asteria and Harmonize were significantly lower than the G-aenial after all brushing cycles (p&lt;0.05). Conclusion: All of the materials demonstrated surface irregularities after 20.000 brushing cycles corresponding to 24 months. The degree of surface alteration increased with brushing time and depends on the composite’s filler rate, size, and shape.

In vitro efficacy of commercial and experimental proteolytic enzyme-based whitening dentifrices on enamel whitening and superficial roughness.

To evaluate the whiteness index (WID ) and surface roughness (Ra) of bovine enamel after simulated tooth brushing with different commercial and experimental whitening dentifrices. Cylindrical enamel bovine specimens were acid etched, stained, and divided in nine groups (n= 8): Colgate® Optic White®, Crest® Baking Soda and Peroxide, Arm and Hammer® Advanced White™ Extreme Whitening, Rembrandt® Deeply White® + Peroxide, Close up® White Attraction Natural Glow, Hinode Prowhite, and experimental dentifrice containing papain (PP), bromelain (PB), or papain and bromelain (PPB). Ra and WID were obtained initially and after 600, 1200, and 3,600 cycles of simulated tooth brushing. Data were analyzed using two-way analysis of variance test (α= 0.05). Ra was significantly influenced by both dentifrice (p= 0.043) and period of tooth-brushing simulation (p< 0.001). Except for PP and PPB, all groups showed a statistically significant increase in Ra after simulated tooth brushing. After staining and brushing, none of the materials tested increased the initial WID . The effect of commercial whitening dentifrices may be related to their high abrasiveness. Experimental formulations tested provided a similar effect without undesired wear of enamel. Whitening dentifrices only act through an abrasive effect rather than bleaching the tooth structures. When used, special care must be taken for avoid undesired wear of enamel. Experimental dentifrices provided similar removal of extrinsic stains without undesired abrasiveness; however, this effect may be due to the use of less aggressive abrasives in their formulations.

Effect of Abrasive Containing Whitening Dentifrices on Surface Characteristics and Color Stability of Two Aesthetic Restorative Materials

surface characteristics and color Stability of two aesthetic restorative materials. Materials and Methods: A total of 180 specimen were prepared from two tested materials (Filtek Z350 resin composite and Equia forte glass ionomer with nano filled coat).The specimen were divided into three groups (n=60). Group 1: hydrated silica containing tooth paste Group 2: calcium carbonate containing tooth paste, Group 3: trisodium phosphate containing tooth paste, each group was subdivided into two subgroups according to number of brushing duration (1120, 2240) cycles (n=15).Each subgroup was further subdivided into three divisions according to the type of test performed (micro hardness, surface roughness, color stability) (n=5). All tests were done before and after brushing then the data were statistically analysed. Results: Baseline results revealed that resin composite has higher micro hardness, lower surface roughness and more color stability compared to glass ionomer. Regarding the effect of tooth paste; trisodium phosphate containing tooth paste recorded the higher micro hardness, lower surface roughness and more color stability among all tested groups. On other hand, brushing for eight weeks (2240cycles) showed significant decrease in micro hardness, increase in both surfaces roughness and color instability. Conclusion: Abrasive containing whitening dentifrices and number of brushing cycles have an influential effect on surface characteristics and color stability of composite and glass ionomer.

Role of desensitizing/whitening dentifrices in enamel wear

ObjectivesTo analyze the impact of desensitizing (D) and/or whitening (W) dentifrices on erosion and erosion-abrasion. MethodsEnamel specimens were allocated into 10 groups (n = 20): 1. Artificial saliva (control); 2. Sensodyne Repair&Protect (SRP–D); 3. Sensodyne Repair&Protect Whitening (SRP–W); 4. Colgate Sensitive Pro-Relief (CSPR–D); 5. Colgate Sensitive Pro-Relief Real White (CSPRR–W); 6. Colgate Total 12 (CT); 7. Colgate Total 12 Professional Whitening (CTP–W); 8. Sensodyne True White (ST–W); 9. Curaprox Black is White (CB–W); 10. Oral-B 3D White Perfection (OB3D-W). For abrasion (n = 10), 30,000 brushing strokes were performed and surface roughness (SR) was evaluated. Erosion-abrasion (n = 10) consisted of 1 % citric acid (2 min), artificial saliva (60 min); 6×/day; 5 days. Toothbrushing was carried out 2×/day (45 strokes). Surface loss (SL) was determined with an optical profilometer. Data were statistically analyzed (α = 0.05). ResultsRelative to SR, only OB3D-W had a significantly rougher surface than the control (p = 0.014). SRP-D, CSPR-D and ST-W showed no difference from the baseline. High SL was observed for ST-W, OB3D-W and CTP-W, without significant differences from the control. CT showed the lowest SL, not differing from SRP–D and SRP–W. There was a weak negative correlation between SL and concentration of free fluoride in the slurries, SL and SR, and SL and pH, all p > 0.05. ConclusionsOnly one dentifrice increased surface roughness of enamel to a higher degree than brushing with saliva. Brushing with the test dentifrices did not cause higher enamel erosive wear than brushing with saliva. Clinical significanceThis study enhances our knowledge on the effect of desensitizing and whitening dentifrices, indicating that they do not worsen enamel loss due to abrasion and they might be a safe option for individuals with erosive tooth wear.

Efficacy and Adverse Effects of Whitening Dentifrices Compared With Other Products: A Systematic Review and Meta-analysis.

Whitening dentifrices (WDs) are widespread and accessible worldwide, claiming to whiten teeth. Therefore, this systematic review aimed to assess the extrinsic stain removal (ESR), the whitening potential, and the adverse effects of WDs. Randomized controlled trials comparing WDs with regular dentifrices (RDs) and other home-based whitening products were searched at NCBI-PubMed, Cochrane-CENTRAL, EBSCO-Host, and clinicaltrials.gov. The studies were screened and had data extracted by two independent researchers. Eligible studies presented outcomes of ESR, color change, and adverse effects, with no restriction of publication date. Data were meta-analyzed using RevMan 5.3, and the level of evidence was rated according to GRADE criteria. Eleven studies (n=1962) assessed reduction of stain area and intensity through Lobene Stain index, with a mean difference (MD) of -0.33 ([-0.41;-0.25]; p=0.00001) and -0.34 ([-0.44;-0.25]; p=0.00001), respectively. When the modified Lobene Stain index was used (six studies; n=2576), MD was -0.42 ([-0.58;-0.25]; p=0.00001) and -0.30 ([-0.39;-0.21]; p=0.00001), respectively. Mean color change through shade guide tabs (three studies; n=1322) was -1.80 ([-2.33;-1.26]; p=0.00001). All differences were in favor of the WDs, which also produced a risk of adverse effects (RR=1.74; [1.20, 2.52]; p=0.003; four studies; n=1322). The comparison of WDs with paint-on gel (two studies; n=58) yielded similar efficacy and adverse effects (p>0.05), whereas the comparison of WDs with white strips (two studies; n=87) yielded higher efficacy of the latter (p=0.00001) and similar adverse effects (p=0.52). The quality of evidence varied from low to moderate. WDs are more effective in reducing extrinsic stain and producing a whitening-like effect in teeth than RDs, although they also produce more adverse effects. Whitening efficacy of WDs is similar to paint-on gel and lower than white strips. Higher-quality evidence demands larger, well-conducted, independent studies.

Optical and Surface Properties of Monolithic Zirconia after Simulated Toothbrushing.

This in vitro study investigated the impact of various dentifrices on the shade, translucency, gloss, and surface characteristics of polishing- or glazing-finished monolithic zirconia surfaces after simulated toothbrushing. Eighty square-shaped monolithic zirconia specimens were divided into two major groups based on the finishing methods—polished (P) and glazed (G). Next, specimens from the two major groups were categorized into four subgroups: stored in distilled water (DW, control); brushed with a fluoride-free conventional dentifrice (C); brushed with a fluoride dentifrice (F); and brushed with a whitening dentifrice (W). Overall, eight groups were created—PDW, PC, PF, PW, GDW, GC, GF, and GW (n = 10 each). Shade, translucency, surface gloss, surface roughness, crystalline phase, and superficial topography data were obtained. Repeated-measures ANOVA and two-way ANOVA were used for intergroup comparison (all α = 0.05). The color differences (ΔE00) between pre- and posttreatment were 0.3158 (PDW), 0.7164 (PC), 0.7498 (PF), 0.8106 (PW), 0.1953 (GDW), 0.301 (GC), 0.3051 (GF), and 0.4846 (GW). A statistically significant difference was observed among the ΔE00, surface gloss, and surface roughness of monolithic zirconia. Thus, brushing with several dentifrices markedly affects the optical properties and surface characteristics of monolithic zirconia finished with polishing or glazing methods.

Efficacy of Dental Bleaching with Whitening Dentifrices: A Systematic Review.

A systematic review was performed to evaluate whether whitening toothpastes promote tooth whitening when compared to the use of conventional (nonbleaching) dentifrices. This review was registered at PROSPERO (CRD42017065132) and is based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Electronic systematic searches of PubMed/MEDLINE, Scopus, and the Cochrane Library were conducted for published articles. Only randomized clinical trials in adults that compared the use of so-called whitening dentifrices to the use of nonwhitening dentifrices were selected. The outcome was tooth color change. Twenty-two articles from 703 data sources met the eligibility criteria. After title and abstract screening, 16 studies remained, after which a further five studies were excluded. In total, nine studies were qualitatively analyzed. Significant differences in tooth color change were found between the groups using whitening dentifrices and those using nonwhitening dentifrices. Within the limitations of this study, the evidence from this systematic review suggests that bleaching dentifrices have potential in tooth whitening. However, although many whitening dentifrices have been introduced into the dental market for bleaching treatments, it is important to analyze tooth surface and color changes when performing home bleaching.

Comparison of Whitening Dentifrices on the Effectiveness of In-office Tooth Bleaching: A Double-blind Randomized Controlled Clinical Trial.

To investigate the effect of whitening dentifrices on the effectiveness of in-office tooth bleaching. A double-blind randomized controlled clinical trial was performed. The participants were randomly allocated into three groups according to the different dentifrices used during this clinical trial: regular dentifrice (group C), conventional whitening dentifrice (group CW), and whitening dentifrice containing blue covarine (group CU). All participants received in-office tooth bleaching for the maxillary anterior teeth (two sessions conducted at a one-week interval). Tooth color was measured with a spectrophotometer at baseline (T1), after the first bleaching session (T2), after the second bleaching session (T3); one week after the completion of in-office bleaching (T4); and three weeks after the completion of in-office bleaching (T5). The data were statistically analyzed through repeated analysis of variance and the Tukey test (α=0.05). Sixty participants completed the study (n=20 per group). At T3, group CU exhibited the lowest ΔE values ( p=0.008). The ΔE values increased from T4 to T5 in the CW and CU groups, whereas a decrease in ΔE values was observed for group C. The use of a whitening dentifrice containing blue covarine during in-office bleaching reduced color changes. After tooth bleaching, brighter tooth colors were observed in the participants who brushed with whitening dentifrices compared to those who brushed with a regular dentifrice.

Influence of whitening dentifrices and mechanical brushing on color change and surface roughness of bulk fill resins

Abstract: The use of whitening dentifrices during oral hygiene may cause surface modifications such as color change (ΔE) and increase surface roughness (Ra) of composite resin. Aim: This study aimed to evaluate the effect of whitening dentifrices and mechanical brushing on color change and surface roughness of Bulk Fill (Filtek Bulk Fill - F) and (Aura Bulk Fill - A) composite resins. Materials and methods: Sixty cylindrical specimens were fabricated of each composite resin. After initial color evaluations (Konica Minolta CM-700d), with D65 standard illuminant, and the surface roughness (Surfcorder SE 1700, Kosalab), the specimens were assigned (n=10) according to the whitening dentifrice used: True White (T), Colgate Total 12 Professional Whitening (D), Luminous White Advanced (L). Specimens were submitted to mechanical brushing (10,000 cycles); new color and surface roughness evaluations were taken. Data were analyzed by ANOVA, Duncan test and Dunnet test were used to identify differences between groups (α=5%). Results: The results showed that the tooth brushing time promoted a significant increase in ΔE of the FT group. The FD group exhibited intermediate values of ΔE and was similar to all groups tested. There was a significant increase in the surface roughness of the AD and AT groups after the mechanical tooth brushing. Conclusion: The results showed no significant changes were observed in surface roughness for F groups after toothbrushing. It be concluded that the color change and surface roughness of the composite resins after toothbrushing are dependent on the interaction between the composition of the composite resin and the characteristics of the dentifrice.

Resinas compostas suprananométricas policromáticas proporcionando estética e função em dentes posteriores

The objective of this six-week, examiner-blind clinical study was to assess the tooth whitening and extrinsic tooth stain removal efficacy of a new dentifrice delivering 1.0% hydrogen peroxide, 0.243% sodium fluoride, and sodium tripolyphosphate in a high-cleaning silica base (Test Dentifrice), relative to that of commercially available hexametaphosphate-containing whitening dentifrice (Positive Control Dentifrice). Following a baseline oral soft tissue examination and scoring of extrinsic tooth stain and tooth shade, qualifying adult male and female subjects from the Harrisburg, Pennsylvania area were randomized into either the Test or Positive Control Dentifrice group. The two groups were balanced for gender, extrinsic tooth stain, and tooth shade scores. All subjects were provided their assigned dentifrice and a soft-bristled adult toothbrush for home use. Subjects were instructed to brush their teeth for two minutes twice daily (morning and evening) using only the dentifrice provided, and to refrain from using any other oral hygiene products for the entire six weeks of the study. There were no restrictions regarding diet or smoking habits during the course of the study. Oral soft tissue, extrinsic tooth stain, and tooth shade assessments for each subject were repeated after two and six weeks of product use. All statistical tests were two sided and employed a level of significance of alpha = 0.05. Fifty-six (56) subjects complied with the protocol and completed the entire study. Compared to baseline at both the two- and six-week examinations, the Test Dentifrice group had statistically significant reductions in extrinsic tooth stain area and intensity, and statistically significant mean shade rank reductions, with a six-week reduction of 4.81. In contrast, at six weeks, the Positive Control dentifrice had a statistically significant increase in tooth stain area, a non-significant increase in tooth stain intensity, and a statistically significant mean 1.40 shade rank score reduction. At both the two- and six-week examinations, the Test Dentifrice group had statistically significantly lighter tooth shades and statistically significantly lower levels of extrinsic tooth stain area and intensity than the Positive Control Dentifrice group. A new whitening dentifrice delivering 1.0% hydrogen peroxide, 0.243% sodium fluoride, and sodium tripolyphosphate in a high-cleaning silica base has significant efficacy in tooth whitening and extrinsic stain removal, and provides a statistically significantly greater level of efficacy for both tooth whitening and extrinsic tooth stain removal than the commercially available Positive Control Dentifrice.

Whitening dentifrice and tooth surface discoloration-a systematic review and meta-analysis.

The aim of this systematic review was to assess the effect of a whitening dentifrice (WDF) relative to a regular dentifrice (RDF) on the reduction of natural extrinsic tooth surface discoloration (ETD). The MEDLINE-PubMed, Cochrane-CENTRAL and EBSCO-Dentistry and Oral Sciences databases were searched, up to April 2017. The inclusion criteria were as follows:(randomized)controlled clinical trials, healthy subjects ≥18years of age, studies comparing WDF with RDF, a follow-up period of at least 6weeks and studies scoring ETD as the stain area/extent, stain intensity or a composite score. Studies using an induced staining model were excluded. Independent screening of 851 unique papers resulted in 21 eligible publications, which included 32 comparisons. The descriptive analysis illustrated that the majority of comparisons showed a significant effect on ETD, in favour of WDF over RDF. The meta-analysis substantiated this observation and revealed that the difference of means (diffM) comparing WDF and RDF was a reduction for stain area of -0.44 [(95% CI: -0.55; -0.339) (P<.00001)] according to the original Lobene Stain Index; this result is in favour of the WDF. For the modified Lobene Stain Index, the diffM was -0.41 [(95% CI: -0.71; -0.10) (P=.009)]. For overall stain intensity, the diffM was -0.35 [(95% CI: -0.44; -0.25) (P<.00001)], and the composite score was -0.39 [(95% CI: -0.57; -0.21) (P<.0001)] and -0.54 [(95% CI: -0.66; -0.43) (P<.00001)]. Subgroup analysis differentiating between products that contained added chemical antidiscoloration agents showed a similar pattern. In this review, nearly all dentifrices that are specifically formulated for tooth whitening were shown to have a beneficial effect in reducing ETD, irrespective of whether or not a chemical discoloration agent was added.

A randomised clinical in situ study to evaluate the effects of novel low abrasivity anti-sensitivity dentifrices on dentine wear

ObjectivesTo compare the abrasive wear on human dentine in an in situ model associated with use of an experimental low abrasivity anti-sensitivity dentifrice containing 1% alumina and 5% sodium tripolyphosphate (STP) with an experimental ultra-low abrasivity non-alumina 5% STP dentifrice, a higher abrasivity daily-use whitening dentifrice, and water as controls. MethodsThis was a single-centre, single-blind, randomised, split-mouth, four-treatment, two-period, crossover in situ study in 29 healthy subjects. Subjects wore bilateral lower buccal appliances, each fitted with four dentine specimens. Study treatments were applied ex vivo (three times daily). Dentine loss was measured by non-contact profilometry after 5, 10 and 15days’ treatment. ResultsAll 29 subjects were included in the efficacy analysis. Significantly less dentine loss was associated with brushing with the low and ultra-low abrasivity dentifrices than with the higher abrasivity dentifrice at all timepoints (p<0.01). Brushing with ultra-low abrasivity dentifrice or water resulted in statistically significantly less dentine loss compared with brushing with the low abrasivity dentifrice at all timepoints (p<0.05). Dentine loss after brushing with ultra-low abrasivity dentifrice was not significantly different from brushing with water. ConclusionsThe degree of dentine loss observed in this in situ model reflected the abrasivity of the study dentifrices. Brushing with low or ultra-low abrasivity STP-containing anti-sensitivity dentifrices resulted in significantly less dentine loss (equating to dentine wear) than with a higher abrasivity daily-use whitening dentifrice.

Effects of whitening dentifrice on yttria-stabilized tetragonal zirconia polycrystal surfaces after simulating brushing

Statement of problemThe changes that occur after brushing yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) are unknown. These changes may favor the retention of microorganisms and chemisorption of water, impairing its longevity. ObjectiveThe purpose of this in vitro study was to evaluate the effects of a whitening dentifrice on Y-TZP surfaces after simulating 10 years of brushing. Material and methodsSeventy-two bar-shaped specimens (20×4×1.2 mm) were divided into 4 groups: storage in distilled water (SW, control), brushing with distilled water (BW), brushing with dentifrice (BD), and brushing with whitening dentifrice (BWD). Brushing was conducted using a linear brushing machine (878400 cycles, 0.98 N, soft toothbrush). The mean roughness (Ra) was analyzed with a profilometer and the superficial topography with scanning electron microscopy (SEM) at baseline and after treatment. Crystalline phases were characterized using x-ray diffraction. Baseline and posttreatment Ra were analyzed using the 1-way ANOVA and Tukey HSD multiple comparison test; the paired t test was used for intragroup comparison (all α=.05). ResultsThe Ra (μm) means (before/after treatment) were SW 0.28/0.28; BW 0.32/0.31; BD 0.28/0.36; BWD 0.30/0.20. No statistically significant difference was found for Ra at baseline (P=.108) than for posttreatment results (P<.001); the BD group had higher Ra values when compared with baseline (P=.019); the BWD group had the lowest values (P<.001). The BD surfaces showed pronounced scratches and detachment of the surface, while BWD showed smoother surfaces; similar crystallographic results among groups were observed. ConclusionsBrushing Y-TZP with conventional dentifrice increased roughness, while brushing with whitening dentifrice reduced roughness. Neither dentifrice changed the crystallographic phases after brushing.

Effects of Bleaching Agents Combined with Regular and Whitening Toothpastes on Surface Roughness and Mineral Content of Enamel.

The purpose of this study was to evaluate surface roughness and changes in the composition of enamel submitted to different bleaching protocols and toothbrushing with regular and whitening toothpastes. Bleaching treatment could promote morphological and chemical changes in enamel surface. Enamel blocks were randomized into nine groups (n=10) according to the bleaching treatment (no bleaching, control group; 6% hydrogen peroxide, HP; or 10% carbamide peroxide, CP) and toothpaste used (placebo, PL; regular, R; or whitening dentifrice, W). Bleaching was performed according to manufacturers' instructions and all groups were submitted to 30,000 cycles of simulated toothbrushing with toothpaste (PL, R, or W). Mineral content evaluation and enamel roughness were evaluated initially (T1), after bleaching (T2), and after toothbrushing (T3), using an energy-dispersive micro X-ray fluorescence spectrometer and profilometry, respectively. Data were statistically analyzed with two way ANOVA, Tukey, and Dunnett tests (5%). Enamel surface roughness was influenced by bleaching and toothbrushing. Surface roughness increased for the groups that brushed with the placebo dentifrice (CP+PL, HP+PL, C+PL) and for the control group that brushed with whitening dentifrice (C+W). Enamel Ca/P ratio decreased after bleaching, but toothbrushing, regardless of the dentifrice used, did not reduce the enamel mineral content. The bleaching treatment resulted in a decrease of enamel mineral content, but the studied dentifrices did not contribute to surface mineral loss.

Influence of whitening and regular dentifrices on orthodontic clear ligature color stability.

This study evaluated the effect of brushing orthodontic clear ligatures with a whitening dentifrice containing a blue pigment (Close Up White Now, Unilever, London, UK) on their color stability, when exposed to a staining agent. Ligatures from 3M Unitek (Monrovia, CA, USA) and Morelli (Sorocaba, SP, Brazil) were tested. Baseline color measurements were performed and nonstained groups (control) were stored in distilled water whereas test groups were exposed for 1 hour daily to red wine. Specimens were brushed daily using regular or whitening dentifrice. Color measurements were repeated after 7, 14, 21, and 28 days using a spectrophotometer based on the CIE L*a*b* system. Decreased luminosity (CIE L*), increased red discoloration (CIE a* axis), and increased yellow discoloration (CIE b* axis) were generally observed for ligatures exposed to the staining agent. Color variation was generally lower in specimens brushed with regular dentifrice, but ligatures brushed with whitening dentifrice were generally less red and less yellow than regular dentifrice. The whitening dentifrice led to blue discoloration trend, with visually detectable differences particularly apparent according to storage condition and ligature brand. The whitening dentifrice containing blue pigment did not improve the ligature color stability, but it decreased yellow discoloration and increased a blue coloration. The use of a whitening dentifrice containing blue pigment during orthodontic treatment might decrease the yellow discoloration of elastic ligatures.