Whitening toothpastes effect on nanoparticle resin composite roughness after a brushing challenge: An in vitro study

Can charcoal-based dentifrices change the color stability and roughness of bleached tooth enamel and resin composites?

Background

Given the increasing prevalence of individuals using charcoal-based dentifrices over extended periods without professional oversight, concerns have emerged regarding their potential effects. This study aimed to investigate the influence of different charcoal-based products on color change (ΔE00), gloss stability, and surface roughness of dental enamel (Intact or bleached) and resin composites subjected to 12-month simulated brushing.

Material and Methods

132 bovine crowns were randomly allocated and restored with either SS-single-shade or conventional multi-shade, NH-nanohybrid, NF- nano-filled, or BF- bulk-fill composite. A conventional toothpaste (Control), a charcoal-based toothpaste (DC) , and a charcoal-based toothpowder (PO) were evaluated corresponding to 1-, 2-, 6-, and 12-month simulated tooth brushing, respectively. Color (ΔE00) and surface roughness (Ra) were assessed at baseline and after each brushing (n=11). Gloss (GU) was assessed before and after brushing. The brushing products, as well as the enamel and composite surfaces, were analyzed using scanning electron microscopy. Color change, gloss stability, and surface roughness were analyzed by a three-way repeated-measures analysis of variance followed by Tukey's test (α=0.05).

Results

Significant differences were found for composite color change (ΔE00) based on brushing product (P<0.001), brushing time (P<0.001), and their interaction (P<0.001), with similar changes across charcoal-based and conventional toothpaste. After 12 months of brushing with toothpowder (PO), all composites exceeded the acceptable ΔE00 threshold. Gloss values decreased significantly (P<0.001), with greater losses in NF and NH resins. Roughness (Ra) also increased more with PO than with toothpaste. Both PO and DC significantly reduced enamel gloss, especially on bleached enamel.

Conclusions

Charcoal-based toothpaste alters the morphology, roughness, gloss, and color of enamel and resin composite, similar to regular toothpaste. Toothpowder creates surface irregularities, decreasing the gloss and increasing the color change and roughness, more strongly impacting bleached enamel and composites after 12-month simulated tooth brushing. Key words:Activated charcoal toothpaste, roughness, gloss, color change, tooth abrasion.

Surface properties and susceptibility to staining of a resin composite after brushing with different whitening toothpastes

Objectives

This study investigated the effects of different whitening toothpaste (WT) on the surface properties and staining susceptibility of a resin composite.

Methods

Cylindrical samples were prepared with a micro-hybrid resin composite and were randomized into groups according to the toothpaste (n = 12): distilled water (DW), regular toothpaste (RT), WT with silica + pyrophosphate (WT-S/P), WT with pentaphosphate and pyrophosphate (WT-P/P), WT with hydrogen peroxide and pyrophosphate (WT-HP/P) and WT with charcoal and pyrophosphate (WT-Ch/P). The samples were brushed for 825 cycles in an automatic brushing machine, simulating 30 days of brushing. After that, an immersion in coffee (10 mL/sample) was performed for 30 minutes for 30 days. The analyses of color, surface microhardness (SMH), and surface roughness (Ra) were performed at the initial time, after brushing with toothpaste and after immersion in coffee. The ΔL*, Δa*, Δb*, ΔEab, Δand E00 values were calculated comparing after toothpaste with initial time and after coffee with after toothpaste. Data were analyzed using a mixed linear model for repeated measures (SMH), Kruskal-Wallis, Dunn, Friedman, and Nemenyi tests, with α = 0.05.

Results

For ΔL*, the WT-Ch/P group had the lowest values and differed from the other groups comparing the after toothpaste with the initial time interval (p < 0.001). The WT-Ch/P group had the lowest SMH values in after-toothpaste time (p < 0.001). In after-toothpaste time and after coffee time, the WT-S/P group had the highest Ra values and differed from the groups except the WT-Ch/P group (p < 0.001).

Conclusions

The toothpaste composition affects the surface characteristics and susceptibility to staining of the resin composite. The charcoal-based toothpaste had the worst performance for the color analyses and SMH.

[Surface roughness of two composite resins after immersion in soda drinks: in vitro study]

Objective

Compare the surface roughness of two composite resins after immersion in carbonated beverages.

Materials and methods

160 resin discs (6 x 2 mm) were divided into 8 groups (n=20 per group) according to type of resin (Filtek™ Z350 XT® and Palfique LX5®) and type of immersion in beverages (distilled water, Coca Cola®, Inca Kola® and Kola Escocesa®. The immersions were carried out under a structured cycle: 4 immersions a day for 5 days, intermediate storage in distilled water and overnight incubation for 8 h at 37°C. The measurements with the roughness meter were evaluated in three times: baseline, 7 and 14 days. The three-way Anova test was used at P<0.05.

Results

Roughness showed differences only for the individual factors of time (P<0.000) and resin (P=0.000), and for the interaction time*drink (P=0.000) and resin*drink (P=0.003). Roughness was higher with Filtek Z350 XT® immersed with Inca Kola® (0.85 ± 0.37) than 14 days compared to other times (P=0.035) and with Palfique LX5 immersed in Coca Cola® at 7 days (1.61 ± 0.42) and in Inca Kola® at 14 days (1.66 ± 0.56) compared to distilled water (P<0,05).

Conclusion

Surface roughness was affected by the type of resin, the type of soft drink and the immersion time. The roughness was greater with the Palfique LX5® nanohybrid resin, the Inca Kola® drink and after 14 days of immersion.

Impact of combined at-home bleaching and whitening toothpaste use on the surface and color of a composite resin

Objective

This in vitro study aimed to evaluate the effects of different whitening toothpastes on a composite resin during at-home bleaching with 10% carbamide peroxide.

Materials and Methods

Sixty samples (7 mm × 2 mm) were used for color and roughness analyses, while another 60 samples (3 mm × 2 mm) were utilized to assess microhardness. The factors analyzed included toothpaste, for which 5 options with varying active agents were tested (distilled water; conventional toothpaste; whitening toothpaste with abrasive agents; whitening toothpaste with abrasive and chemical agents; and whitening toothpaste with abrasive, chemical, and bleaching agents). Brushing and application of whitening gel were performed for 14 days. Surface microhardness (SMH), surface roughness (Ra), and color (∆L*, ∆a*, ∆b, ∆E*ab, and ∆E00) were analyzed. The Ra and SMH data were analyzed using mixed generalized linear models for repeated measures, while the color results were assessed using the Kruskal-Wallis and Dunn tests.

Results

Between the initial and final time points, all groups demonstrated significant increases in Ra and reductions in SMH. No significant differences were found between groups for SMH at the final time point, at which all groups differed from the distilled water group. Conventional toothpaste exhibited the lowest Ra, while whitening toothpaste with abrasive agent had the highest value. No significant differences were observed in ∆L*, ∆a*, and ∆b.

Conclusions

While toothpaste composition did not affect the color stability and microhardness of resin composite, combining toothbrushing with whitening toothpaste and at-home bleaching enhanced the change in Ra.

Evaluation of the effects of whitening toothpaste containing nanohydroxyapatite on surface roughness and color change in restorative materials

Background

The effects of whitening toothpastes containing nanohydroxyapatite on the surfaces of restorative materials are not well known. This study evaluated the changes in surface roughness and color of coffee-stained restorative materials after brushing with nanohydroxyapatite and other whitening toothpastes.

Methods

Disc-shaped specimens were formed using microhybrid, nanohybrid, and supra-nano-filled composite (n = 30) and stained with a coffee solution. A brushing simulation was applied with toothpastes containing nanohydroxyapatite (Dentiste Plus White), perlite (Signal White System) and hydrogen peroxide (Colgate Optic White) for 7, 15, and 30 days. Color and surface roughness measurements were taken before and after brushing. Color change (∆E₀₀) was calculated using the CIEDE2000 system.

Results

Supra-nano-filled composite-Dentiste Plus White, supra-nano-filled composite-Colgate Optic White, and nanohybrid composite-Signal White System were the groups with the greatest color change observed on the 7th, 15th, and 30th days, respectively. The smallest color change was seen in the microhybrid composite-Signal White System, microhybrid composite-Dentiste Plus White, and nanohybrid composite-Dentiste Plus White groups on the 7th, 15th, and 30th days, respectively. No significant surface roughness changes were observed in the nanohybrid composite-Dentiste Plus White, supra-nano-filled composite-Colgate Optic White, supra-nano-filled composite-Dentiste Plus White, or supra-nano-filled composite-Signal White System groups.

Conclusions

Whitening toothpaste containing nanohydroxyapatite provided a high degree of color change in the short term and did not create significant surface roughness in nanohybrid or supra-nano-filled composites.

Influences of Toothbrushing and Different Toothpastes on the Surface Roughness and Color Stability of Interim Prosthodontic Materials

The surface properties and color stability of interim crown materials may vary depending on the toothbrushing procedure. This study aimed to investigate the effects of toothbrushing and different toothpastes on the surface roughness (Ra) and color stability of different interim crown materials. Disc-shaped specimens were prepared from four interim crown materials (Tab 2000 (ChPM), Imident (LaPM), Protemp 4 (ChDM), and Telio-CAD (CadPM)). Specimens were divided into four subgroups for the control group (Cnt) and for simulated toothbrushing with distilled water (Dw) or with two different toothpastes (whitening toothpaste (WTp), activated charcoal toothpaste (ACTp)). The specimens’ Ra values were measured before and after 10,000 cycles of toothbrushing. The color parameters were measured and the color differences (ΔE00) were calculated. Data were statistically analyzed by two-way analysis of variance (ANOVA) and Tukey’s HSD tests. A significant increase in the Ra values was observed after toothbrushing, except for the LaPM_Dw, ChDM_Dw, and all the CadPM specimens (p < 0.05). Toothbrushing with toothpastes increased the ΔE00 values of all ChPM and ChDM interim materials (p < 0.05). Before and after all toothbrushing procedures, the CadPM specimens had smoother and ChPM specimens had rougher surfaces than the other interim materials. The two tested toothpastes had similar effects on the Ra of all interim materials. Non-perceivable color changes were seen only with the CadPM_Dw group.

Nanoparticles as Next-Generation Tooth-Whitening Agents: Progress and Perspectives

Whitening agents, such as hydrogen peroxide and carbamide peroxide, are currently used in clinical applications for dental esthetic and dental care. However, the free radicals generated by whitening agents cause pathological damage; therefore, their safety issues remain controversial. Furthermore, whitening agents are known to be unstable and short-lived. Since 2001, nanoparticles (NPs) have been researched for use in tooth whitening. Importantly, nanoparticles not only function as abrasives but also release reactive oxygen species and help remineralization. This review outlines the historical development of several NPs based on their whitening effects and side effects. NPs can be categorized into metals or metal oxides, ceramic particles, graphene oxide, and piezoelectric particles. Moreover, the status quo and future prospects are discussed, and recent progress in the development of NPs and their applications in various fields requiring tooth whitening is examined. This review promotes the research and development of next-generation NPs for use in tooth whitening.

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

Objectives

To 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 methods

Sixty-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.

Results

Changes 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.

Conclusion

The 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.

Glass Fiber Reinforced Composite Orthodontic Retainer: In Vitro Effect of Tooth Brushing on the Surface Wear and Mechanical Properties

Fiber reinforced composites (FRCs) are metal free materials that have many applications in dentistry. In clinical orthodontics, they are used as retainers after active treatment in order to avoid relapse. However, although the modulus of the elasticity of FRCs is low, the rigidity of the material in the form of a relatively thick retainer with a surface cover of a flowable resin composite is known to have higher structural rigidity than stainless steel splints. The aim of the present study is to measure load and bending stress of stainless steel wires, as well as flowable resin composite covered and spot‑bonded FRC retainer materials after tooth brushing. These materials were tested with a three point bending test for three different conditions: no brushing, 26 min of brushing, and 60 min of brushing. SEM images were taken before and after different times of tooth brushing. Results showed that stainless steel was not significantly affected by tooth brushing. On the other hand, a significant reduction of values at maximum load at fracture was reported for both FRC groups, and uncovered FRCs were most affected. Concerning maximum bending stress, no significant reduction by pretreatment conditions was reported for the materials tested. SEM images showed no evident wear for stainless steel. Flowable resin composite covered FRCs showed some signs of composite wear, whereas spot‑bonded FRCs, i.e., without the surface cover of a flowable resin composite, showed signs of wear on the FRC and exposed glass fibers from the FRC's polymer matrix. Because of the significant changes of the reduction of maximum load values and the wear for spot‑bonded FRCs, this technique needs further in vitro and in vivo tests before it can be performed routinely in clinical practice.