Which whitening toothpaste with different contents is more effective on color and bond strength of enamel?

Whitening Efficacy of Toothpastes on Coffee-Stained Teeth: An Enamel Surface Analysis

AIM

This study aimed to identify the optimal toothpaste for removing coffee-induced stains while also evaluating its impact on tooth enamel through roughness and abraded depth parameters, providing a comprehensive understanding of their effects.

MATERIALS AND METHODS

Three whitening toothpastes and 2 conventional toothpastes were prepared for a simulated brushing procedure on coffee-stained bovine enamel tooth specimens. Using a toothbrushing machine, up to 10,000 brushstrokes were completed, while spectrophotometric readings were taken at designated intervals. A mixed-effects model for statistical analysis determined the effects of toothpaste and brushing on colour change, roughness, and abraded depth.

RESULTS

Whitening toothpastes significantly deviated from the control (P < .001, P < .001, and P < .003, respectively), whereas the conventional toothpaste did not exhibit a significant contrast (P < .081). Regarding colour restoration following coffee staining, whitening toothpastes showed higher restoration than conventional toothpastes. Surface roughness and abraded depth parameters increased with accumulated brushing.

CONCLUSIONS

Sodium hexametaphosphate-containing toothpaste demonstrated the highest efficacy in removing coffee-induced stains and restoring tooth colour. Nevertheless, this stronger whitening effect was associated with increased abrasion. While conventional toothpastes exhibited some whitening effects, the most substantial improvement in lightness was consistently observed with whitening toothpastes.

CLINICAL RELEVANCE

Understanding how whitening toothpaste affects enamel integrity is crucial for refining formulations and advancing dental care. This knowledge lays the groundwork for more effective oral care products and improved whitening procedures, ultimately enhancing the overall quality of dental treatments.

Effect of whitening toothpastes on the surface roughness and microhardness of human teeth-an in vitro study

OBJECTIVE

To determine the effect of whitening toothpastes on the surface roughness and microhardness of human teeth.

METHODOLOGY

Surface roughness was estimated using the Talysurf instrument, and microhardness was estimated using the Vickers hardness tester before and after the application of whitening toothpastes on mounted extracted human teeth.

RESULTS

In the activated charcoal group, there was a reduction in the surface roughness from 1.21 at baseline to 1.09 at 1 month and a further reduction to 1.02 at 3 months, which was found to be statistically significant. However, no statistically significant difference in surface roughness was found in the other toothpaste groups. With respect to microhardness, all 4 whitening toothpastes showed a statistically significant reduction in microhardness after 3 months of brushing. However, the reduction was significantly higher in group 2 and in group 4 compared to the others.

CONCLUSION

This study showed that whitening toothpaste containing activated charcoal significantly reduced the surface roughness, whereas toothpastes with blue covarine and toothpastes containing activated charcoal significantly reduced the microhardness of the tooth.

CLINICAL RELEVANCE

This study emphasizes the need for healthcare professionals to be aware of the potential disadvantages of whitening toothpastes and make evidence-based decisions when recommending the product to patients.

Effects of a commercial whitening toothpaste containing hydrogen peroxide and citric acid on dentin abrasion and erosion

BACKGROUND

Hydrogen peroxide (HP) and citric acid (CA), key contributors to toothpaste acidity, can lead to dental loss. This study aimed to compare the amount of abrasion or loss of dentin based on pH, buffering, and concentration of HP and CA in commercial and experimental toothpastes after toothbrushing or immersion.

METHODS

Bovine dentin specimens were randomly assigned to nine solutions. The prepared solutions included two commercial toothpastes (whitening toothpaste [WT] with HP and CA; conventional toothpaste [CT] without HP and CA), reference slurry (RS), two CA solutions (1.92%, CAS1; 0.001%, CAS2), basic solution (7.16% sodium phosphate dibasic [SPDS]), CA phosphate buffer solution (3.58% SPDS and 0.96% CA [CAPB]), HP solution (4%, HPS), and distilled water (DW). Dentin specimens were performed in two treatments: one with only abrasion (10,000 brushings) and one with only immersion (1 h). After treatments, the amount of dentin loss and surface images were measured and observed using noncontact profilometry. Data were analyzed using an one-way analysis of variance and the Tukey test as a post hoc analysis (p < 0.05).

RESULTS

WT with pH 5.0 had lower dentin abrasion than CT and RS after brushing but had higher dentin loss than both after immersion. The dentin surfaces of CAS1, CAPB, and WT were damaged after immersion, whereas HPS, CAS2, CT, SPDS, RS, and DW remained intact after soaking. CAS2 and HPS, which had a pH of 5.0 like WT, did not significantly differ from those of DW after brushing.

CONCLUSIONS

WT containing HP and CA did not cause significant dentin abrasion but may cause additional dentin loss even without brushing. After brushing or immersion, the CA concentration may affect the dentin surface more than the HP concentration included in WT. The amount of abrasion or loss of dentin after brushing or soaking can vary based on the composition, concentration, and buffer in the solution, even if the pH of the solution is similar to pH 5.0.

Evaluation of the Efficacy of Low-Particle-Size Toothpastes against Extrinsic Pigmentations: A Randomized Controlled Clinical Trial

Stain-removing domiciliary protocols are focused on the elimination of dental extrinsic pigmentations by the application of abrasive toothpastes, extensively available in commerce. The goal of the present study is to evaluate the efficacy of two different stain removal molecule-formulated toothpastes by the reduction of clinical parameters: the micro-cleaning crystals and activated charcoal. A total of 40 participants with extrinsic dental pigmentations were enrolled and divided into two groups: a Control group, assigned to a toothpaste with micro-cleaning crystals (Colgate Sensation White); and a Trial group, with microparticle-activated charcoal toothpaste (Coswell Blanx Black). At T0 (baseline), T1 (10 days), T2 (1 month), and T3 (3 months), clinical parameters, including Lobene stain index calculated for intensity and extension, plaque control record, and bleeding on probing, were measured. Statistically significant differences were found in both groups (p < 0.05): a reduction of extrinsic pigmentation, both in intensity and extension, was obtained in the Control group, but their total elimination could be achieved only in the Trial group with the activated charcoal molecule, though without significant difference between the groups (p > 0.05). No intergroup differences were found for each timeframe for PCR, BoP, LSI-I, and LSI-E. Both tested toothpastes can be recommended for domiciliary oral hygiene of patients with extrinsic pigmentations.

Characterization of whitening toothpastes and their effect on the physical properties of bulk-fill composites

To characterize activated charcoal and 2% hydrogen peroxide-based toothpastes and investigate their effects on roughness, color change, and gloss of bulk-fill composite resin. Composite resin specimens (Aura Bulk Fill, SDI) were subjected to 5,000 brushing cycles with regular toothpaste (Colgate Total 12, [RT]), activated charcoal toothpaste (Bianco Dental Carbon, [AC]), or hydrogen peroxide-containing toothpaste (Colgate Luminous White Advanced, [HP]), with or without coffee exposure. The pH, particle characterization by scanning electron microscopy (SEM), and weight% of solid particles in the toothpaste were assessed. Roughness (Ra) was evaluated using a surface profile-measuring device, color change (∆Eab/∆E00) by reflectance spectrophotometer, and gloss unit (GU) by glossmeter. Kruskal-Wallis, Dunn, Friedman, and Nemenyi tests were used, and the correlation coefficient test was performed between Ra and GU (α=0.05). RT presented a higher Ra after brushing and did not change after staining with coffee; moreover, the ∆Eab/∆E00 values were higher for RT than HP. Regarding gloss, AC and HP obtained higher values compared to RT. A significant negative correlation between gloss and Ra was found for RT exposed to coffee. All toothpastes had a neutral pH; however, RT had the largest percentage of solids by weight. SEM images showed particles of many sizes: irregular shape (RT), more regular particles (AC), and spherical clusters (HP). Although surface roughness, color change, and gloss may compromise the longevity of restorations, the whitening toothpastes tested did not promote more morphology changes than regular toothpastes.