Influence of using different toothpaste during bleaching with violet LED light (405 nm) on the colour and roughness of dental enamel: an in vitro study.

This in vitro study aimed to investigate potential changes in the color and roughness of dental enamel resulting from the use of different toothpaste formulations during bleaching with violet LED light (405 nm). Sixty specimens of bovine incisors, each measuring 6 × 6 × 3 mm, were segregated into six distinct experimental groups based on their respective treatments (n = 10): C + VL: Brushing with Colgate® Total 12 + bleaching with violet LED; LB + VL: Brushing with Colgate® Luminous White Brilliant + bleaching with violet LED; LI + VL: Brushing with Colgate® Luminous White Instant + violet LED bleaching; C: Brushing with Colgate® Total 12; LB: Brushing with Colgate® Luminous White Brilliant; LI: Brushing with Colgate® Luminous White Instant. The examined variables included alterations in color (∆L*, ∆a*, ∆b*, ∆Eab, and ∆E00), surface roughness (Ra), and scanning electron microscopy observations. No statistically significant distinctions emerged in total color variations (∆E00 and ∆E) among the groups under scrutiny. Notably, the groups that employed Colgate® Luminous White Instant displayed elevated roughness values, irrespective of their association with violet LED, as corroborated by scanning electron microscopy examinations. It can be concluded that whitening toothpastes associated to violet LED do not influence the color change of dental enamel in fifteen days of treatment. Toothpastes with a higher number of abrasive particles showed greater changes in enamel roughness, regardless of the use of violet LED.

Evaluation of Relative Dentin Abrasivity in Whitening Toothpastes Containing Acids.

INTRODUCTION AND AIMS: This study aimed to evaluate the relative dentin abrasivity of whitening toothpastes containing acids using the Radioactive Dentin Abrasivity - Profilometry Equivalent (RDA-PE). METHODS: A total of 100 bovine dentin specimens were prepared and assigned to the following groups (n = 10): 5 hydrogen peroxide (HP) whitening toothpastes (WTH1-WTH5) with or without acid (citric acid, ethylenedinitrilotetraacetic acid disodium, and phosphoric acid), 2 whitening toothpastes with silica and containing citric or phosphoric acid (WTS1 and WTS2), one conventional toothpaste (CT), and 2 reference slurries (RS). All specimens were brushed for 4,000 or 10,000 strokes using toothbrush and toothbrushing machine. The average dentin depth was measured using a noncontact profilometery, and the RDA-PE value was calculated based on the RS. The pH of the solution, average particle size, particle content, and particle hardness were measured. The RDA-PE data were analysed using one-way analysis of variance and Tukey's test, and the effects of the 4 measured factors on RDA-PE were investigated via multiple regression analysis. RESULTS: The RDA-PE values of the HP whitening toothpastes (mean value: 19-46) were significantly lower, whereas those of the silica whitening toothpastes (80 or 111) were similar to those of the RS after 4,000 strokes (100). The RDA-PE values of all whitening toothpastes were significantly lower than the RS values after 10,000 strokes (242). The HP whitening toothpastes were slightly acidic (pH ≤6) compared to the other solutions. The HP (2.9%-3.7%) and silica (8.9% or 9.9%) whitening toothpastes had significantly lower particle content than RS (16.6%). The particle content significantly influenced the RDA-PE values by multiple regression results. CONCLUSIONS: The RDA-PE values of whitening toothpastes varied. The particle content in the solution was a key factor affecting the RDA-PE value. CLINICAL RELEVANCE: Whitening toothpastes containing acids did not cause significant dentin abrasion.

Over-the-counter products in tooth bleaching: A scoping review.

OBJECTIVE: To map and summarize the current scientific evidence concerning the active ingredients, effectiveness, and adverse effects of over-the-counter (OTC) bleaching products. DATA AND SOURCE: This study was conducted according to the PRISMA-ScR guidelines for scoping reviews and registered on the Open Science Framework platform. STUDY SELECTION: Database searches were conducted in PubMed/MEDLINE, Embase, and Scopus up to January 2024. All in vitro, in situ, and clinical studies evaluating the effectiveness and adverse effects of OTC bleaching products were included. A descriptive analysis of the included studies was performed. RESULTS: A total of 88 studies were included. Most of them were in vitro studies (n = 49), followed by randomized clinical trials (n = 28). The main OTC bleaching products identified were whitening or stain-removing toothpastes (n = 42), followed by whitening strips (n = 39). Most clinical studies indicate that whitening strips are effective in improving tooth color and providing whitening benefits. In contrast, the bleaching effectiveness of toothpastes, mouth rinses and whitening trays was mainly supported by in vitro studies. The main adverse effects associated with OTC bleaching agents were tooth sensitivity and gingival irritation. CONCLUSION: A wide variety of OTC bleaching products is available for consumer self-administered use. Clinical studies have mainly confirmed the bleaching effectiveness of whitening strips, while the validation for toothpastes, mouth rinses and whitening trays has mainly relied on in vitro studies. Nevertheless, the use of OTC bleaching products may result in adverse effects, including tooth sensitivity, gingival irritation, and enamel surface changes. CLINICAL SIGNIFICANCE: Some over-the-counter bleaching products may have whitening properties supported by clinical studies, particularly those containing hydrogen or carbamide peroxide. Nonetheless, clinicians must be aware of the potential risks associated with excessive self-administration of these products, which may result in adverse effects.

In-office dental bleaching in adolescents using 6% hydrogen peroxide with and without gingival barrier: a randomized double-blind clinical trial.

BACKGROUND: At low concentrations used for in-office bleaching gels, such as 6% HP, gingival barrier continues to be performed. If we take into account that, in the at-home bleaching technique, no barrier is indicated, it seems that the use of a gingival barrier fails to make much sense when bleaching gel in low concentration is used for in-office bleaching. OBJECTIVE: This double-blind, split-mouth, randomized clinical trial evaluated the gingival irritation (GI) of in-office bleaching using 6% hydrogen peroxide (HP) with and without a gingival barrier in adolescents, as well as color change and the impact of oral condition on quality of life. METHODOLOGY: Overall, 60 participants were randomized into which side would or would not receive the gingival barrier. In-office bleaching was performed for 50 minutes with 6% HP in three sessions. The absolute risk and intensity of GI were assessed with a visual analogue scale. Color change was assessed using a digital spectrophotometer and color guides. The impact of oral condition on quality of life was assessed using the Brazilian version of the Oral Health Impact Profile (α=0.05). RESULTS: The proportion of patients who presented GI for the "with barrier" group was 31.6% and for the "without barrier" group, 30% (p=1.0). There is an equivalence for the evaluated groups regarding GI intensity (p<0.01). Color change was detected with no statistical differences (p>0.29). There was a significant impact of oral condition on quality of life after bleaching (p<0.001). CONCLUSIONS: The use or not of the gingival barrier for in-office bleaching with 6% HP was equivalent for GI, as well as for bleaching efficacy, with improvement in the impact of oral condition on quality of life.

Assessment of color changes and adverse effects of over-the-counter bleaching protocols: a systematic review and network meta-analysis.

OBJECTIVES: To assess color change efficacy and the adverse effects of varied over-the-counter (OTC) bleaching protocols. METHODOLOGY: The study included randomized clinical trials evaluating color changes from OTC bleaching agents. Nine databases were searched, including the partial capture of the grey literature. The RoB2 tool analyzed the individual risk of bias in the studies. Frequentist network meta-analyses compared treatments through common comparators (∆Eab* and ∆SGU color changes, and tooth sensitivity), integrating direct and indirect estimates and using the mean and risk differences as effect measures with respective 95% confidence intervals. The GRADE approach assessed the certainty of the evidence. RESULTS: Overall, 37 remaining studies constituted the qualitative analysis, and ten composed the meta-analyses. The total sample included 1,932 individuals. ∆Eab* was significantly higher in groups 6% hydrogen peroxide (HP) strips (≥ 14 h). ∆SGU was significantly higher in groups at-home 10% carbamide peroxide (CP) (≥ 14 h), followed by 6% HP strips (≥ 14 h) and 3% HP strips (≥ 14 h). At-home 10% CP (7-13 h) and placebo showed lower risks of tooth sensitivity without significant differences between these treatments. CONCLUSION: Considering the low level of evidence, OTC products presented satisfactory short-term effects on tooth bleaching compared to the placebo, with little to no impact on dentin hypersensitivity and gingival irritation. CLINICAL RELEVANCE: OTC products are proving to be practical alternatives for tooth whitening. However, patients should be advised about the possible risks of carrying out such procedures without professional supervision.

Effect of topical application of ibuprofen/arginine on the in-office bleaching-induced tooth sensitivity: A randomized, triple-blind controlled trial.

OBJECTIVE: The application of anti-inflammatories as topical desensitizers before dental bleaching is an approach to reduce bleaching-induced tooth sensitivity (TS). This randomized controlled trial compared the risk and intensity of TS and the color change resulting from in-office dental bleaching after using an experimental desensitizing gel containing ibuprofen and arginine. METHODS: Sixty-two participants with upper canine shades A2 or darker were randomly assigned to either the ibuprofen-arginine desensitizing group or the placebo group. The desensitizing gel was applied for 15 min before in-office bleaching with 35 % hydrogen peroxide gel for 50 min (2 sessions). To assess the absolute risk and intensity of TS, visual (0-10) and numeric rating (0-5) scales were used, and group comparisons were made using the McNemar test, Wilcoxon test, and paired Student t-test (α = 0.05). Color change was evaluated using Vita Classical, Vita Bleachedguide (ΔSGU), and Vita EasyShade (ΔEab, ΔE00, and ΔWID) before and one month after the bleaching procedure. Group comparisons for color change were done using a paired t-test (α = 0.05). RESULTS: The odds ratio for TS was 0.14 [95 % CI 0.02 to 0.6], meaning lower odds of TS for the desensitizing gel. A lower intensity of TS was also observed for the experimental group (p < 0.005) up to 48 h after bleaching. All color evaluation tools demonstrated effective and similar whitening for both groups (p > 0.05). CONCLUSIONS: Using the experimental desensitizing gel containing ibuprofen and arginine effectively reduced the risk and intensity of TS without compromising the bleaching efficacy. CLINICAL RELEVANCE: The topical application of ibuprofen/arginine on the in-office bleaching reduced risk and intensity of bleaching-induced tooth sensitivity.

Effect of gingival barrier brands on operator perception, cervical adaptation, and patient comfort during in-office tooth bleaching: a randomized clinical trial.

BACKGROUND: Light-cured resins are widely used as gingival barriers to protect the gums from highly concentrated peroxides used in tooth bleaching. The impact of barrier brand on clinical outcomes is typically considered negligible. However, there is limited evidence on the effects of different brands on operator experience, barrier adaptation, and patient comfort. OBJECTIVE: This clinical trial assessed the impact of four commercial gingival barrier brands (Opaldam, Topdam, Lysadam, and Maxdam) on operator perception, adaptation quality, and patient comfort. METHODS: Twenty-one undergraduate students placed gingival barriers in a randomized sequence using blinded syringes. Photographs of the barriers were taken from frontal and incisal perspectives. After bleaching procedures, operators rated handling features and safety using Likert scale forms. Two experienced evaluators independently assessed barrier adaptation quality on a scale from 1 (perfect) to 5 (unacceptable). The absolute risk of barrier-induced discomfort was recorded. Data were analyzed using Friedman and Chi-square tests (α = 0.05). RESULTS: Opaldam and Topdam received the highest scores in most handling features, except for removal, which was similar among all brands. No significant difference was observed in barrier adaptation quality between the evaluated brands. Discomforts were mainly reported in the upper dental arch, with Maxdam having the highest absolute risk (35% for this arch and 24% overall). CONCLUSIONS: This study suggests that gingival barrier brands can influence operator perception and patient comfort. Opaldam and Topdam were preferred by operators, but all brands demonstrated comparable adaptation quality. CLINICAL TRIAL REGISTRATION: The study was nested in a randomized clinical trial registered in the Brazilian Clinical Trials Registry under identification number RBR-9gtr9sc.

Efeito do pH do gel clareador de consultório na cor e na sensibilidade dentária / Effect of the pHof the in-office tooth bleaching gelon color and tooth sensitivity / Efecto del pH del gel blanqueador dental de consultorio sobre el color y la sensibilidad dental

Introdução:Sabe-se que a busca pela estética é algo cada vez mais crescente. Dentre os procedimentos mais procurados na odontologia estética, destaca-se o clareamento dental de consultório. Diante disso, ainda são poucos os estudos que avaliam os efeitos dos agentes clareadores de diferentes pHs na efetividade clareadora e na sensibilidade dentária.Objetivo:Avaliar a sensibilidade dentária e a eficácia clareadora de géis clareadores à base de peróxido de hidrogênio a 35% com diferentes pHs.Metodologia:Trata-se de um relato de três casos, descritivo e observacional, do tipo boca dividida (split-mouth) para cada estratégia clareadora (gel clareador com pH básico e gel clareador com pH ácido). Foram avaliados três pacientes de25, 26e 27anos de idade.Realizou-se registro de cor por meio da escala VITAClassical e avaliação da sensibilidade dentária pela escala visual analógica. Resultados:Todos os pacientes avaliados apresentaram cor A3 no registro de cor inicial e, após o clareamento dental,atingiram a cor A1. Todos relataram uma maior sensibilidade no hemiarco direito (local onde foi aplicada o gel clareador Whiteness HP que possui pH ácido. Dois pacientes relataram sensibilidade dentária no hemiarco esquerdo em que foi aplicado o gel clareador de pH básico. Conclusões:Observa-se a eficácia clínica dos géis clareadores de consultório à base de peróxido de hidrogênio a 35% na estabilidade de cor após o tratamento clareador, independente do seu pH. Ademais, nota-se que o gel clareador de pH básico promoveu menor sensibilidade pós-operatória (AU).

Introduction:It is known that the search for aesthetics is something increasingly growing. Among the most sought-after procedures in cosmetic dentistry, in-office tooth bleaching stands out. Therefore, there are still few studies that evaluate the effects of bleaching agents ofdifferent pHs on bleaching effectiveness and tooth sensitivity.Objective:To evaluate tooth sensitivity and bleaching efficacy of 35% hydrogen peroxide-based tooth bleaching gels with different pHs.Methodology:This is a report of three cases, descriptive and observational, of the split-mouth type for each bleaching strategy (bleaching gel with basic pH and bleaching gel with acidic pH). Three patients aged 25, 26 and 27 years were evaluated. Color registration was performed using the VITA Classical scale and tooth sensitivity was evaluated using the visual analogue scale.Results:All evaluated patients presented color A3 in the initial color registration and, after tooth bleaching, reached color A1. All reported greater sensitivity in the right hemi-arch (place where the Whiteness HP bleaching gel with an acid pH was applied. Two patients reported tooth sensitivity in the left hemi-arch where the basic pH bleaching gel was applied.Conclusions:The clinical efficacy of in-office tooth bleaching gels based on 35% hydrogen peroxide in terms of color stability after bleaching treatment is observed, regardless of its pH. In addition, it is noted that the basic pH bleaching gel promoted less postoperative sensitivity (AU).

Introducción: Se sabe que la búsqueda de la estética es algo cada vez más creciente. Entre los procedimientos más populares en odontología estética, se destaca el blanqueamiento dental en consultorio. Ante esto, aún existen pocos estudios que evalúen los efectos de agentes blanqueadores de diferentes pHs sobre la efectividad del blanqueamiento y la sensibilidad dental.Objetivo: Evaluar la sensibilidad dental y la eficacia blanqueadora de geles blanqueadores a base de peróxido de hidrógeno al 35 % con diferentes pH. Metodología: Este es un reporte de tres casos, descriptivo y observacional, del tipo boca partida para cada estrategia de blanqueamiento (gel blanqueador con pH básico y gel blanqueador con pH ácido). Se evaluaron tres pacientes de 25, 26 y 27 años. El registro de color se realizó con la escala clásica VITA y la sensibilidad dental se evaluó con la escala analógica visual.Resultados: Todos los pacientes evaluados presentaron color A3 en el registro de color inicial y, después del blanqueamiento dental, alcanzaron el color A1. Todos refirieron mayor sensibilidad en la hemiarcada derecha (lugar donde se aplicó el gel blanqueador de pH ácido Whiteness HP). Dos pacientes refirieron sensibilidad dental en la hemiarcadaizquierda donde se aplicó el gel blanqueador de pH básico.Conclusiones: Se observala eficacia clínica de los geles blanqueadores de consultorio a base de peróxido de hidrógeno al 35% en cuanto a la estabilidad del color tras el tratamiento blanqueador, independientemente de su pH. Además, se observa que el gel blanqueador de pH básico promovió una menor sensibilidad postoperatoria (AU).

Bleaching gel volume influences hydrogen peroxide diffusion, inflammation, and the presence of nitric oxide in the pulp tissue: in vitro and in vivo model.

OBJECTIVE: To assess whether bleaching gel volume influences chromatic changes, hydrogen peroxide (HP) diffusion, inflammation, and oxidative stress in the pulp tissue. METHODOLOGY: A total of 60 bovine teeth were divided into four groups, according to bleaching gel volume (n=15): without gel (WG); V30 (30 µL of 35% HP); V60 (60 µL); and V120 (120 µL). HP diffusion analysis was performed in the first session (T1). Chromatic changes (ΔE, ΔE00, and WID) were assessed after the first (T1), second (T2), third (T3) sessions, and 15 d (T4) after the end of treatment. Moreover, 20 rats were randomly divided into four groups (n=10) and their upper first molars were treated with different gel volumes: control (no treatment); V2 (2 µL of 17.5% HP); V4 (4 µL); and V8 (8 µL). After 24 h, rats were euthanized and the specimens processed for histological and immunohistochemical (nitric oxide synthase) evaluation. Data were analyzed using the Wilcoxon and Mann-Whitney tests (p<0.05). RESULTS: In vitro (bovine teeth), chromatic changes were not influenced by bleaching gel volume, showing similar values in all groups and sessions, except for the control group (p<0.05). The V120 group had the highest HP diffusion values (p<0.05). In vivo (pulp tissue), the V4 and V8 groups showed the highest inflammatory infiltrate in the pulp and significant oxidative stress (p<0.05). CONCLUSION: The adverse effects on the dental pulp related to HP diffusion, pulp inflammation, and oxidative stress depend on bleaching gel volume, while the bleaching effect is not proportional to the volume used.

Influence of bleaching gels formulated with nano-sized sodium trimetaphosphate and fluoride on the physicochemical, mechanical, and morphological properties of dental enamel.

OBJECTIVES: To evaluate in vitro the effects of sodium fluoride (F) and nano-sized sodium trimetaphosphate (TMPnano) added to a 35% hydrogen peroxide (H2O2) bleaching gel on the color alteration, enamel mechanical and morphological properties, and H2O2 transamelodentinal diffusion. MATERIALS AND METHODS: Bovine enamel/dentin discs (n = 180) were divided according to the bleaching gel: 35% H2O2 (HP); 35% H2O2 + 0.1% F (HP/F); 35% H2O2 + 1% TMPnano (HP/TMPnano); 35% H2O2 + 0.1% F + 1% TMPnano (HP/F/TMPnano) and 35% H2O2 + 2% calcium gluconate (HP/Ca). The gels were applied 3 times by 40 min; once each 7-day. The Commission Internationale de l'Eclairage (CIE) L*a*b* total color alteration (ΔE), color alteration by CIEDE2000 (ΔE00), whitening index (ΔWID), surface (SH) and cross-sectional hardness (ΔKHN), surface roughness (Ra), and transamelodentinal diffusion were determined. Enamel surfaces were evaluated by Scanning Electron Microscopy (SEM) and X-ray Dispersive Energy (EDX). Data were submitted to ANOVA, followed by the Student-Newman-Keuls test (p <0.05). RESULTS: ΔE, ΔE00, and ΔWID were similar among the gels that promoted a bleaching effect after treatment (p <0.001). Mineral loss (SH and ΔKHN), Ra, and H2O2 diffusion were lower for HP/F/TMPnano; the HP and HP/Ca groups presented the highest values (p <0.001). For SEM/EDX, surface changes were observed in all bleached groups, but less intense with TMPnano. CONCLUSIONS: Gels containing F/TMPnano do not interfere with the bleaching effect and reduce enamel demineralization, roughness, H2O2 diffusion, and morphological changes. CLINICAL RELEVANCE: Whitening gels containing F/TMPnano can be used as a new strategy to increase safety and maintain clinical performance.