RESUMEN

BACKGROUND: To predict the long-term performance of restorative materials in the oral environment, it is important to evaluate their resistance to chemical and mechanical degradation and to know the toxic potential of the type and amount of ions eluted from the filling material. In this study, home bleaching was applied to dental materials with different contents and it was aimed to determine the type and amount of ions released from these materials. METHODS: In this study, amalgam, posterior composite resin, anterior composite resin, bulk fill composite resin, indirect composite resin, hybrid ceramic and all-ceramic were used as restorative materials. 10 specimens of each material were prepared according to the manufacturer's instructions. Each material group was divided into two subgroups as the bleached group and the control group. After bleaching, all specimens were stored in 1 ml of 75% ethanol/water solution. Solutions were renewed after 1, 14 and 28 days. The type and amount of ions released from the materials were determined using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Data were analyzed using the Friedman, Wilcoxon Signed Ranks, and Mann-Whitney U tests (α = 0.05). RESULTS: It was determined that the amount of ions release from the restorative materials decreased over time (p < 0.05). According to the results of the Mann-Whitney U test, there was no difference between the bleaching and control groups in most of the restorative materials (p > 0.05). CONCLUSION: Within the limits of this study, home bleaching system does not have a significant effect on ion release from restorative materials.

Asunto(s)

Peróxido de Carbamida , Resinas Compuestas , Amalgama Dental , Materiales Dentales , Restauración Dental Permanente , Ensayo de Materiales , Peróxidos , Blanqueadores Dentales , Urea , Peróxido de Carbamida/farmacología , Peróxidos/química , Resinas Compuestas/química , Blanqueadores Dentales/química , Amalgama Dental/química , Urea/análogos & derivados , Urea/química , Restauración Dental Permanente/métodos , Materiales Dentales/química , Iones , Cerámica/química , Humanos , Factores de Tiempo

RESUMEN

OBJECTIVE: This study aims to synthesize, characterize, and assess the penetration of hydrogen peroxide (HP), color change (CC), and surface morphology changes after the application of two distinct nano-hydroxyapatite (nano-HAp). METHODS: Two nano-HAp were previously synthesized by co-precipitation: one with rod-shaped particles (RS) and the other with spherical-shaped particles (SS). The surface charge of the nano-HAp particles was determined at varying pH levels and characterized by X-ray diffraction patterns and Fourier transform infrared spectroscopy. The morphology of the samples was assessed using scanning electron microscopy (SEM). The nano-HAp particles were applied before the dental bleaching procedure. Forty teeth were divided into four groups (n = 10) according to the bleaching treatment: no treatment, bleaching with 35 % HP only, RS application and bleaching with 35 % HP, and SS application and bleaching with 35 % HP. HP concentration (µg mL-1) was measured using UV-Vis, while CC was evaluated with a digital spectrophotometer (ΔEab, ΔE00 and WID). Additionally, four teeth from each group were selected for SEM analysis. Statistical analysis encompassed one-way ANOVA, Tukey's, and Dunnet's tests. RESULTS: RS and SS were successfully synthesized by coprecipitation, primarily differing in pH during synthesis. Both variations of nano-HAp morphology significantly reduced HP diffusion into the pulp chamber (p < 0.001). Regarding enamel morphology, groups analyzed post dental bleaching exhibited greater HAp deposition on the enamel surface. Notably, this deposition did not impede CC. SIGNIFICANCE: The utilization of different nano-HAp morphologies prior to dental bleaching appears to be a promising strategy for mitigating adverse effects associated with dental bleaching procedures.

Asunto(s)

Esmalte Dental , Peróxido de Hidrógeno , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Blanqueadores Dentales , Blanqueamiento de Dientes , Difracción de Rayos X , Blanqueamiento de Dientes/métodos , Esmalte Dental/efectos de los fármacos , Humanos , Blanqueadores Dentales/química , Blanqueadores Dentales/administración & dosificación , Espectroscopía Infrarroja por Transformada de Fourier , Concentración de Iones de Hidrógeno , Color , Nanopartículas/química , Hidroxiapatitas/química , Durapatita/química , Ensayo de Materiales

RESUMEN

OBJECTIVE: Evaluate the penetration of hydrogen peroxide (HP) into the pulp chamber, bleaching efficacy (BE) and amount of gel expended during in-office bleaching using an applicator brush tip and conventional tip from different commercial brands. MATERIALS AND METHODS: 104 human premolars were randomly distributed into thirteen groups (n = 8) according to the commercial brand: DSP White Clinic 35 % Calcium (DW), Nano White 35 % (NW), Total Blanc One-Step 35 % (TS), Whiteness HP Blue 35 % (WB), Potenza Bianco Pro SS 38 % (PB), Opalescence XTra Boost 40 % (OB), no bleaching (negative control), and application method: applicator brush tip and conventional tip for all groups. Initial HP concentration (%) was determined via titration and pH was measured with digital pH meter. Concentration (µg/mL) of HP into the pulp chamber was measured using UV-Vis spectrophotometry, the BE (ΔE*ab, ΔE00 and ΔWID) was evaluated with a digital spectrophotometer, and the amount of gel expended was evaluated using a precision analytical digital balance. Statistical analysis included two-way ANOVA, Tukey's, and Dunnett's test. Comparison between HP into the pulp chamber vs BE was performed with Person's correlation (α = 0.05). RESULTS: Brush tip demonstrated a low amount of HP in the pulp chamber compared to the conventional method for all bleaching gels (p < 0.0003), as well as lower amount of gel expended (p < 0.002). The brush tip did not result in a significant difference in BE compared to the conventional (p > 0.05). No correlations were found between both factors (p > 0.05). CONCLUSION: Brush tip showed lower penetration of HP in the pulp chamber and a reduced volume of spent gel when compared to the conventional tip, for all commercial brands. CLINICAL RELEVANCE: Brush tip is recommended for bleaching gels in an attachable syringe due to its ability to reduce the penetration of HP into the pulp chamber and minimize the amount of bleaching gel used.

Asunto(s)

Geles , Peróxido de Hidrógeno , Blanqueadores Dentales , Blanqueamiento de Dientes , Humanos , Peróxido de Hidrógeno/química , Blanqueamiento de Dientes/métodos , Blanqueamiento de Dientes/instrumentación , Blanqueadores Dentales/administración & dosificación , Blanqueadores Dentales/química , Blanqueadores Dentales/farmacocinética , Cavidad Pulpar , Jeringas , Diente Premolar , Concentración de Iones de Hidrógeno , Ensayo de Materiales , Color

RESUMEN

OBJECTIVES: To evaluate the effect of whitening toothpastes with different hydrogen peroxide (HP) concentrations on HP permeability, color change, and physicochemical properties, compared to at-home bleaching treatment. MATERIALS AND METHODS: Forty-nine premolars were randomized into seven groups (n = 7): untreated (control); at-home bleaching with 10% carbamide peroxide gel (AH; 10% CP) with 14 and 28 applications of 180 min each (AH [14 × 180 min] and AH [28 × 180 min]); three whitening toothpastes (3% HP; 4% HP and 5% HP) and 10% CP brushed 28 times for 90 s each (TB [28 × 90 s]). HP permeability was measured using a UV-VIS spectrophotometer and color change by a digital spectrophotometer (ΔEab, ΔE00, and ΔWID). Initial concentration, pH, and viscosity were measured through titration, digital pH meter, and rheometer, respectively. Statistical analysis included one-way ANOVA, Tukey's test, and Dunnett's test (α = 0.05). RESULTS: 4% HP group showed acidic pH, the lowest viscosity and the highest HP concentration into the pulp chamber (p < 0.05). The 10% CP groups had lower HP in the pulp chamber and greater color change than other groups (p < 0.05), except the 5% HP group in ΔEab and ΔE00. For ΔWID, the 10% CP AH groups showed greater whitening than other groups (p < 0.05). CONCLUSIONS: Whitening toothpaste with up to 5% HP resulted in higher HP permeability and less color change compared to 10% CP. Higher HP commercial concentrations in toothpaste increased whitening effect; however, acidic pH toothpastes exhibited greater HP permeability. CLINICAL RELEVANCE: Whitening toothpastes with high hydrogen peroxide concentrations were less effective than at-home bleaching, resulting in less color change and greater permeability of hydrogen peroxide, potentially increasing the risk of tooth sensitivity.

Asunto(s)

Peróxido de Carbamida , Peróxido de Hidrógeno , Espectrofotometría , Blanqueadores Dentales , Blanqueamiento de Dientes , Pastas de Dientes , Blanqueamiento de Dientes/métodos , Pastas de Dientes/química , Humanos , Blanqueadores Dentales/química , Técnicas In Vitro , Diente Premolar , Viscosidad , Concentración de Iones de Hidrógeno , Espectrofotometría Ultravioleta , Urea/análogos & derivados , Urea/farmacología

RESUMEN

BACKGROUND: To evaluate the decomposition rate of active hydrogen peroxide (HP) and bleaching efficacy during in-office bleaching using high-concentration HP gels with different pHs. METHOD: A randomized, parallel, double-blind controlled trial was conducted with 40 volunteers randomized into four groups (pH 5.4; pH 7.0; pH 7.7, and pH 8.0). During the first session in-office bleaching, approximately 0.01 g of the gel was collected and titrated with potassium permanganate to obtain the concentration of active HP and pH values were measured using an electrode. Bleaching efficacy was assessed using a spectrophotometer [∆Eab, ∆E00, and WID], Vita Classical and Vita Bleachedguide scales [∆SGU]. The decomposition rate of HP concentration and pH values change were calculated using ANOVA one-way. The bleaching efficacy was assessed using two-way repeated measures ANOVA. Tukey's test was applied as a post-hoc test (p < 0.05). RESULTS: All gels experienced decreasing HP concentration over time. pH 5.4 gel showed greatest reduction after 50 min (p < 0.001). pH 8.0 and 7.7 gels remained stable; pH 5.4 remained acidic, while pH 7.0 turned acidic (p < 0.001). No significant difference in bleaching degree was observed among gels. They all showed a similar and clinically important color change after two clinical sessions, remained stable 1-month post-treatment (p > 0.05). CONCLUSIONS: All bleaching gels kept at least 70% of their HP content after 50 min, suggesting that there is a surplus of HP. They provided similar whitening efficacy 1-month after bleaching. PRACTICAL IMPLICATIONS: It is possible that lower HP concentrations may be equally effective in achieving desired results while reducing the potential for side effects. CLINICAL TRIAL REGISTRY NAME: RBR-35q7s3v.

Asunto(s)

Geles , Peróxido de Hidrógeno , Blanqueadores Dentales , Blanqueamiento de Dientes , Humanos , Método Doble Ciego , Blanqueadores Dentales/química , Concentración de Iones de Hidrógeno , Peróxido de Hidrógeno/química , Blanqueamiento de Dientes/métodos , Femenino , Masculino , Adulto , Espectrofotometría , Resultado del Tratamiento

RESUMEN

Aims - to compare the color changes, the surface roughness and morphology of the enamel bleached with two different bleaching solutions (chemical and laser activated), preceded or not with acid etching. Thirty teeth of bovine prepared and haphazardly assigned to 2 groups (n=15) depending on bleaching technique. Each group subdivided to 3 subgroup (n=5) consistent with acid etching by 37% phosphoric acid. Atomic force microscopy and VITA easy shade spectrophotometer were performed twice for all the specimens before and after bleaching. ANOVA, the Paired sample t-test, and the independent sample t-test used for statistical analysis. As for the color changes, the groups that were bleached by the chemical method, the difference among the three subgroups was statistically significant. This also applies to the groups bleached with the laser method. When comparing the results of the chemical bleaching subgroups with the laser bleaching ones, the difference was not significant. Roughness results showed significant differences between certain subgroups and non-significant differences among others. However, the difference was statistically significant between the chemical and laser groups, laser technique resulted in less surface roughness than the chemical one. Acid etching before bleaching produced better colour change in both the chemical and laser assisted bleaching. In chemical bleaching, surface roughness was higher when acid etching was used. This was also true for laser bleaching technique. In general, laser assisted bleaching produced less surface roughness than chemical bleaching.

Asunto(s)

Grabado Ácido Dental , Esmalte Dental , Propiedades de Superficie , Blanqueamiento de Dientes , Esmalte Dental/efectos de los fármacos , Esmalte Dental/química , Bovinos , Animales , Blanqueamiento de Dientes/métodos , Propiedades de Superficie/efectos de los fármacos , Color , Ácidos Fosfóricos/química , Ácidos Fosfóricos/farmacología , Microscopía de Fuerza Atómica , Blanqueadores Dentales/química , Blanqueadores Dentales/farmacología , Espectrofotometría , Rayos Láser

RESUMEN

OBJECTIVES: This study assessed the effects of 15% and 20% carbamide peroxide (CP) on color, surface roughness, and hardness of computer-aided design/computer-aided manufacturing (CAD/CAM) dental ceramics. MATERIALS AND METHODS: This in vitro study was conducted on 120 Vita Mark II, Celtra Duo, and Suprinity CAD/CAM ceramic specimens. The ceramic specimens in each group (n = 40) were randomly assigned to two subgroups (n = 20) for polishing and glazing, and their baseline color, surface roughness (Ra), and hardness were assessed. In each subgroup, half of the specimens were exposed to 15% CP, while the other half were exposed to 20% CP. Their color change (ΔE), surface roughness, and hardness were then measured again. Surface roughness, hardness, and color were analyzed sequentially by profilometer, Vickers hardness tester, and spectrophotometer, respectively. Data were analyzed by repeated measures ANOVA, one-way ANOVA, and post hoc Bonferroni test (α = 0.05). RESULTS: The surface roughness of all groups significantly increased after bleaching treatment (p < 0.05). Surface hardness of all groups decreased after bleaching treatment, but this reduction was only significant in Vita Mark II subgroups (glazed, polished, 15%, and 20% CP). The ΔE was not clinically and visually perceivable in any group. CONCLUSION: The present results revealed that concentration of CP and type of surface treatment affected the surface properties of CAD/CAM ceramics. Type of surface treatment only affected the surface hardness of Vita Mark II ceramics (p < 0.05). Concentration of CP had a significant effect only on polished Vita Mark II.

Asunto(s)

Peróxido de Carbamida , Cerámica , Color , Diseño Asistido por Computadora , Dureza , Ensayo de Materiales , Peróxidos , Propiedades de Superficie , Peróxido de Carbamida/química , Propiedades de Superficie/efectos de los fármacos , Dureza/efectos de los fármacos , Cerámica/química , Peróxidos/química , Porcelana Dental/química , Urea/química , Urea/análogos & derivados , Urea/farmacología , Blanqueadores Dentales/química , Humanos , Técnicas In Vitro , Materiales Dentales/química , Espectrofotometría

RESUMEN

BACKGROUND: This study aimed to investigate the effect of whitening toothpastes on the color stability and surface roughness of resin composites stained with coffee and cigarette smoke. METHODS: Seventy-two disk-shaped specimens (6 × 2 mm) of suprananohybrid resin composite were randomly divided into two groups and exposed to coffee and cigarette smoke (n = 36). After staining, the samples randomly divided into four groups according to whitening toothpastes and were brushed for 4 min: Opalescence Whitening (OW); Colgate Optic White (COW); Curaprox Black is White (CPX) and, distilled water (control) (n = 9). Color was measured with spectrophotometer at the initial, after staining, and after brushing, and surface roughness was measured with profilometer at the initial and after brushing. A surface morphology analysis was examined using scanning electron microscopy and atomic force microscopy. The obtained data were statistically analyzed. (p < 0.05). RESULTS: Cigarette smoke caused a significantly higher color change than coffee in the resin composite (p < 0.05). Brushing with hydrogen peroxide and silica-containing whitening toothpaste showed significant differences in color change (p < 0.05). The lowest whitening effect was found in activated charcoal-containing toothpaste. While all toothpastes increased the degree of surface roughness of resin composites, the highest roughness was caused by whitening toothpastes containing activated charcoal. (p < 0.05). CONCLUSIONS: The color stability and surface properties of resin composites can be affected by brushing them with whitening toothpaste. The utilization of whitening toothpaste containing hydrogen peroxide can be considered a safe method for increasing the whiteness of discolored resin composites.

Asunto(s)

Café , Color , Resinas Compuestas , Propiedades de Superficie , Blanqueadores Dentales , Pastas de Dientes , Resinas Compuestas/química , Pastas de Dientes/química , Blanqueadores Dentales/química , Microscopía Electrónica de Rastreo , Espectrofotometría , Peróxido de Hidrógeno/química , Microscopía de Fuerza Atómica , Cepillado Dental , Blanqueamiento de Dientes/métodos , Ensayo de Materiales , Humanos , Dióxido de Silicio/química

RESUMEN

This study aimed to assess the effects of dental bleaching on the immediate shear bond strength (SBS) of composite to enamel. Different bleaching methods and time intervals between bleaching and composite restoration were examined. A total of 45 enamel specimens were divided into three groups (n = 15) based on the applied bleaching protocol: in-office (A), at-home (B), and unbleached control (C). Groups A and B were then subdivided into three time intervals until bonding: 1, 3, and 7 days. The composite was bonded to enamel using self-etch adhesive technique and submitted to SBS testing. The enamel surface and adhesive interface were observed under scanning electron microscope (SEM). The highest average SBS was measured in the control (unbleached) group (31.1 ± 3.4). A significant difference in SBS was found between the control and in-office bleaching (p < .001), as well as between control and at-home bleaching (p = .034), while the difference between in-office and at-home bleaching methods was insignificant. In relation to the waiting period, a significant reduction in SBS (p < .001) was found 1 day post-bleaching. The weakest marginal sealing to enamel under SEM was observed also 1 day after bleaching. Both bleaching methods significantly reduced the SBS of composite to enamel, especially immediately after the bleaching procedure. Reduction in SBS is temporary and 3-day waiting period seems to be sufficient to reverse the adverse effects of bleaching. RESEARCH HIGHLIGHTS: SBS of composite to enamel is significantly reduced by bleaching procedures, especially immediately after bleaching. The reduction in SBS is temporary and reversible by delaying the restoration for a minimum of 3 days.

Asunto(s)

Resinas Compuestas , Recubrimiento Dental Adhesivo , Esmalte Dental , Microscopía Electrónica de Rastreo , Resistencia al Corte , Blanqueamiento de Dientes , Esmalte Dental/efectos de los fármacos , Esmalte Dental/química , Blanqueamiento de Dientes/métodos , Humanos , Resinas Compuestas/química , Recubrimiento Dental Adhesivo/métodos , Blanqueadores Dentales/química , Propiedades de Superficie

RESUMEN

OBJECTIVE: To evaluate the effects of different polishing techniques and coffee staining on the color stability of four commercially available bleach-shade composite resins, namely microhybrid, nanohybrid, nanofilled, and injectable nanohybrids. MATERIAL AND METHODS: A total of 224 discs (8 mm diameter and 2 mm thickness) were fabricated from four different bleach-shade composite resins, namely microhybrid (Gradia Direct Anterior), nanohybrid (Palfique LX5), nanofilled (Filtek Universal), and injectable nanohybrid (flowable G-aenial universal injectable). The composite resin groups were polished via four techniques: no polishing, 4-step polishing using aluminum oxide discs, 3-step polishing using silicon rubber diamond discs, and one-step polishing. Half of each group was immersed in water, while the other half was immersed in coffee for 12 days (n = 7). Colors were measured using a clinical spectrophotometer, and color differences were calculated (ΔE). The results were analyzed statistically. RESULTS: The alterations in color were significantly influenced by the techniques employed for finishing and polishing techniques, composite resin type, and degree of coffee staining. Regardless of the polishing technique and storage medium, different material types showed a significant color change (ΔE) at P < 0.001. Filtek exhibited the most significant color change, followed by Gradia and Palfique, with no significant differences between them. In addition, Different polishing techniques resulted in significant color changes (P < 0.001). The highest degree of color change was seen in the no-polishing group, followed by the 4-step and 1-step polishing groups, with negligible differences between each other. Also, Storage media had a significant effect on ΔE values. CONCLUSION: Appropriate finishing and polishing procedures can improve the color stability of bleach-shaded composite resins. Coffee has a deleterious effect on color; however, injectable flowable nanohybrid composites are more resistant to staining.

Asunto(s)

Óxido de Aluminio , Café , Color , Resinas Compuestas , Pulido Dental , Propiedades de Superficie , Resinas Compuestas/química , Pulido Dental/métodos , Óxido de Aluminio/química , Ensayo de Materiales , Espectrofotometría , Técnicas In Vitro , Humanos , Diamante/química , Nanocompuestos/química , Blanqueadores Dentales/química , Agua/química , Materiales Dentales/química , Factores de Tiempo

RESUMEN

BACKGROUND: To investigate the effect of a 50% ascorbic acid with 50% citric acid solution on the immediate shear bond strength (SBS) of metallic brackets after tooth bleaching. The enamel etching pattern and the required quantity of these combined acids as antioxidants following 35% hydrogen peroxide (HP) bleaching were also determined. METHODS: The stability of the solution at room temperature was assessed at various time intervals. Fifty teeth were randomly divided into five groups: non-bleached (G1), bleached then acid etched (G2), bleached followed by a 10-minute treatment with 10% sodium ascorbate and acid etched (G3), 5-minute treatment with 50% ascorbic acid (G4), and 5-minute treatment with a combination of 50% ascorbic acid and 50% citric acid (G5). Groups G2, G3, G4 and G5 were bleached by 35% HP gel for a total of 32 min. Acid etching in groups G1, G2, and G3 was performed using 37% phosphoric acid (Ormco®, Orange, CA, USA) for 15 s. In all groups, metal brackets were immediately bonded using Transbond™ XT primer and Transbond™ PLUS adhesive, with light curing for 40 s. The SBS was tested with a universal testing machine, and statistical analysis was conducted using one-way ANOVA followed by Tukey's HSD test. The level of significance was set at p < 0.05 for all statistical tests. RESULTS: Stability tests demonstrated that the combined acids remained effective for up to 21 days. Group G5 significantly increased the SBS of bleached teeth to the level of G1 (p < 0.05), while G3 did not achieve the same increase in SBS (p > 0.05). SEM analysis revealed enamel etching patterns similar to those of both control groups (G1 and G2). Kinetic studies at 6 min indicated that the antioxidation in G5 reacted 0.2 mmole lower than in G3 and G4. CONCLUSION: 5-minute application of the combined acids enhanced the SBS of bleached teeth comparable to unbleached teeth. The combined acids remain stable over two weeks, presenting a time-efficient, single-step solution for antioxidant application and enamel etching in orthodontic bracket bonding.

Asunto(s)

Ácido Ascórbico , Ácido Cítrico , Recubrimiento Dental Adhesivo , Esmalte Dental , Soportes Ortodóncicos , Resistencia al Corte , Blanqueamiento de Dientes , Ácido Ascórbico/farmacología , Ácido Cítrico/farmacología , Ácido Cítrico/química , Blanqueamiento de Dientes/métodos , Humanos , Proyectos Piloto , Esmalte Dental/efectos de los fármacos , Recubrimiento Dental Adhesivo/métodos , Grabado Ácido Dental , Antioxidantes/farmacología , Propiedades de Superficie , Factores de Tiempo , Peróxido de Hidrógeno/química , Blanqueadores Dentales/química , Ácidos Fosfóricos , Análisis del Estrés Dental

RESUMEN

OBJECTIVES: The aim of this study was to compare the effect of office bleaching of teeth bonded with Transbond XTTM (3M Unitek, Monrovia, CA, USA) (TRXT) and the use of color change resistant Orthocem (FGM, Joinville, Brazil) in bracket bonding on coffee-induced enamel discoloration. MATERIALS AND METHODS: Eighty premolars were distributed in equal numbers (n = 20) to group 1 (TRXT + distilled water), group 2 (TRXT + coffee solution), group 3 (TRXT + coffee solution + bleaching), and group 4 (Orthocem + coffee solution). Color was measured using a SpectroShade Micro (MHT, International, Verona, Italy) device at the beginning (T0), after coloring (T1), after bleaching (T1B), and after debonding (T2). ΔE color change values were calculated as T1-T0, T1B-T0 and T2-T0 differences. The conformity of the data to the normal distribution was examined with the Shapiro-Wilk test. Multiple comparisons were made with Tamhane's T2 test and Tukey's HSD test using one-way analysis of variance in the comparison of normally distributed data, and multiple comparisons were made with Dunn's test using the Kruskal-Wallis H test for comparison of non-normally distributed data. The significance level was set at p < 0.050. RESULTS: A statistically significant (p < 0.001) difference was found between the T1-T0 and T2-T0 stages for group 1-4 ΔE values. A statistically significant (p < 0.001) difference was also found when the T1B-T0 ΔE values of group 3 were compared with the T1-T0 ΔE values of groups 1, 2, and 4. CONCLUSIONS: After coffee-induced enamel discoloration, bleaching of teeth bonded with TRXT produced acceptable color difference of the incisal, middle, and gingival regions of the crown. In teeth bonded with Orthocem, acceptable color difference was seen only in the middle of the crown. CLINICAL RELEVANCE: The presented study will guide the clinician on how enamel discoloration side effect of fixed orthodontic appliance can reduce.

Asunto(s)

Soportes Ortodóncicos , Blanqueamiento de Dientes , Decoloración de Dientes , Humanos , Técnicas In Vitro , Blanqueamiento de Dientes/métodos , Blanqueamiento de Dientes/efectos adversos , Decoloración de Dientes/inducido químicamente , Propiedades de Superficie , Diente Premolar , Blanqueadores Dentales/química , Café , Cementos de Resina/química , Color , Recubrimiento Dental Adhesivo/métodos , Ensayo de Materiales

RESUMEN

OBJECTIVES: This study evaluated the efficacy of simulated brushing with toothpastes containing different concentrations of hydrogen peroxide (HP) in pulp chamber penetration and color change. Also, physical-chemical properties (concentration, pH and viscosity) were evaluated. METHODS: Forty-nine premolars were divided into seven groups (n = 7): untreated (control); whitening gel (White Class 6 %, 6 %BG) with one 90  min application (6 %BG 90  min) and 14 applications of 90  min (6 %BG 14×90 min); toothpastes (Colgate Luminous White Glow 3 %, 3 %TP; Crest 3D White Brilliance 4 %, 4 %TP; Colgate Optic White Pro-Series 5 %, 5 %TP) and 6 %BG toothbrushing for 14 applications of 90 s. HP penetration into the pulp chamber was measured through UV-Vis spectrophotometry and color change with a spectrophotometer (ΔEab, ΔE00, and ΔWID). Initial concentration, pH, and viscosity were measured through Titration, Digital pH-meter, and Rheometer, respectively. Statistical analysis used one-way ANOVA and Tukey's test (α = 0.05). RESULTS: 6 %BG (14×90 min) and 4 %TP groups showed acidic pH and higher concentrations of HP in the pulp chamber compared to the other groups (p < 0.05). On the other side, 3 %TP and 5 %TP groups showed alkaline pH, higher viscosity between the toothpastes and lower HP penetration (p < 0.05). The 6 %BG AH (14×90 min) group exhibited the most significant color change (ΔEab, ΔE00, and ΔWID) (p < 0.05). CONCLUSIONS: Brushing with whitening toothpaste with an acidic pH leads to greater HP penetration into pulp chamber; but, even when a high concentrated HP whitening toothpaste was used, a lower whitening effect was observed when compared to a two-week at-home bleaching. CLINICAL SIGNIFICANCE: Whitening toothpastes containing up to 5 % HP produced lower whitening effect than two-week at-home bleaching. Additionally, HP was detected within the pulp chamber which can potentially impact in tooth sensitivity.

Asunto(s)

Color , Cavidad Pulpar , Peróxido de Hidrógeno , Blanqueadores Dentales , Blanqueamiento de Dientes , Cepillado Dental , Pastas de Dientes , Peróxido de Hidrógeno/química , Humanos , Blanqueadores Dentales/farmacocinética , Blanqueadores Dentales/química , Concentración de Iones de Hidrógeno , Pastas de Dientes/química , Blanqueamiento de Dientes/métodos , Cavidad Pulpar/metabolismo , Viscosidad , Ensayo de Materiales , Factores de Tiempo , Espectrofotometría , Diente Premolar , Espectrofotometría Ultravioleta

RESUMEN

AIM: To evaluate the bleaching efficacy and effects on enamel properties of experimental gels with carbamide peroxide (CP; 10%) or hydrogen peroxide (HP; 6%) containing calcium polyphosphate sub-microparticles (CaPPs). METHODS: A total of 216 bovine tooth specimens were divided for microhardness and color analyses (n = 108) and block randomized into nine groups (n = 12): (G1) commercial CP (Whiteness Perfect, FGM; Brazil); (G2) experimental CP; (G3) CP-0.5%CaPPs; (G4) CP-1.5%CaPPs; (G5) commercial HP (Potenza Bianco, PHS; Brazil); (G6) experimental HP; (G7) HP-0.5%CaPPs; (G8) HP-1.5%CaPPs; (G9) artificial saliva. The gels' pH values were determined with a bench pH meter. Color (ΔE, ΔE00, ΔWID) and microhardness variation were evaluated before and after the therapy. Part of the specimens used for microhardness was submitted to the scanning electron microscopy (SEM) (n = 3) and energy-dispersive X-ray spectroscopy EDX (n = 3) analyses. Statistical analyses were performed in the R statistical software (α = 0.05). Linear mixed models for repeated measures in time were used to analyze microhardness and L* values. Generalized linear models were used to analyze the a*, b*, ΔE, ΔE00, and ΔWID, considering a group effect. The EDX data were analyzed using a one-way ANOVA with Tukey's test. RESULTS: The gels' pH remained over 6,0. All gels effectively bleached the specimens and did not differ significantly. When compared to the control group, the hardness was significantly lower in the G1, G2, G6, and G7 groups. The G3, G4, G5, and G8 groups did not differ significantly (p > 0.05). CONCLUSION: The incorporation of CaPPs in low-concentration whitening gels reduces its negative effects on microhardness without interfering with their bleaching efficacy.

Asunto(s)

Peróxido de Carbamida , Esmalte Dental , Geles , Peróxido de Hidrógeno , Microscopía Electrónica de Rastreo , Polifosfatos , Blanqueadores Dentales , Blanqueamiento de Dientes , Bovinos , Esmalte Dental/efectos de los fármacos , Animales , Peróxido de Hidrógeno/química , Blanqueadores Dentales/farmacología , Blanqueadores Dentales/química , Polifosfatos/farmacología , Polifosfatos/química , Blanqueamiento de Dientes/métodos , Peróxido de Carbamida/farmacología , Dureza , Propiedades de Superficie , Espectrometría por Rayos X , Técnicas In Vitro , Color , Peróxidos/farmacología , Urea/análogos & derivados , Urea/farmacología , Urea/química , Concentración de Iones de Hidrógeno , Tamaño de la Partícula

RESUMEN

Introdução: O efeito branqueador dos dentifrícios contendo Blue covarine é fundamentado no seu mecanismo de ação, caracterizado pela sua deposição na superfície dentária, alterando a percepção da cor. Objetivo: Revisar a literatura e buscar evidência científica sobre o efeito branqueador do Blue Covarine em tecidos mineralizados e materiais restauradores estéticos. Materiais e métodos: Para a revisão da literatura foram feitas buscas nas bases de dados PubMed, LILACS, BBO, SciELO e MEDLINE para identificar estudos clínicos e laboratoriais que avaliassem a ação branqueadora do agente óptico Blue covarine. Como estratégia de busca foram utilizados os descritores "Blue covarine", "Blue covarine e pasta de dentes", "Blue covarine and toothpaste", "Blue covarine e dentifrícios", "Blue covarine and dentifrices", "Blue covarine e dentifrícios branqueadores", "Blue covarine and whitening dentifrices", "Blue covarine e dentifrícios clareadores", "Blue covarine and bleaching dentifrices", "Blue covarine e pasta de dentes branqueadoras", "Blue covarine and whitening toothpaste", "Blue covarine e pasta de dentes clareadoras", "Blue covarine and bleaching toothpaste". Resultados: Dois pesquisadores selecionaram e analisaram criticamente 31 artigos, sendo 2 revisões da literatura, 4 estudos clínicos e 25 estudos laboratoriais. Divergências quanto ao desenho de estudo, métodos, amostra, critérios clínicos e parâmetros laboratoriais foram observados, além de conflitos de interesse. Conclusão: O Blue Covarine presente nos dentifrícios branqueadores parece ser efetivo na promoção do branqueamento dentário apenas quando associado aos agentes abrasivos presentes nas formulações, evidenciando que ensaios clínicos e laboratoriais, com metodologias semelhantes, são necessários para se obter evidência científica conclusiva sobre o efeito deste agente branqueador.(AU)

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Introduction: The whitening effect of dentifrices containing Blue Covarine is based on its mechanism of action, characterized by its deposition on the tooth surface, altering the perception of color. Objective: To review the literature and seek scientific evidence on the whitening effect of Blue Covarine on mineralized tissues and aesthetic restorative materials. Materials and methods: For the literature review, searches were carried out in the PubMed, LILACS, BBO, SciELO and MEDLINE databases, in order to identify clinical and laboratory studies that evaluated the whitening action of the optical agent Blue Covarine. As a search strategy, the descriptors "Blue Covarine", "Blue Covarine and toothpaste", "Blue Covarine and dentifrices", "Blue Covarine and whitening dentifrices", "Blue Covarine and bleaching dentifrices", "Blue Covarine and whitening toothpaste", "Blue Covarine and bleaching toothpaste". Results: Two researchers selected and critically analyzed 31 articles, including 2 literature reviews, 4 clinical studies and 25 laboratory studies. Differences in study design, methods, sample, clinical criteria and laboratory parameters were observed, in addition to conflicts of interest. Conclusion: Blue Covarine present in whitening dentifrices seems to be effective in promoting dental whitening only when associated with abrasive agents present in the formulations, showing that clinical and laboratory tests, with similar methodologies, are necessary to obtain conclusive scientific evidence on the effect of this bleaching agent.(AU)

Asunto(s)

Humanos , Blanqueamiento de Dientes/métodos , Dentífricos/química , Isoindoles/química , Blanqueadores Dentales/química , Metaloporfirinas/química , Colorimetría , Esmalte Dental/química

RESUMEN

This study aimed to evaluate the effect of human saliva in vitro and salivary flow in situ on the roughness and mineral content of bleached enamel. Dental specimens were divided into five groups (n=15): not bleached (NB); bleached (35% hydrogen peroxide) and exposed to distilled water (DW); human saliva in vitro (IV); normal salivary flow in situ (NSF); and low salivary flow (LSF) in situ. Enamel roughness (Ra, Rz) and calcium/phosphorus contents were evaluated with laser profilometry and energy-dispersive spectroscopy, respectively, at baseline (T1), after bleaching (T2), and after seven days (T3). Salivary pH and buffer capacity were evaluated with colorimetric strips and salivary calcium and phosphorus with absorbance spectrophotometry. Data were analyzed with non-parametric tests and linear regression (α=0.05). After contact with saliva, Ra and Rz of LSF=DW>IV=NSF=NB was found. For DW and LSF, the roughness of T1

Asunto(s)

Blanqueadores Dentales , Blanqueamiento de Dientes , Humanos , Blanqueamiento de Dientes/métodos , Blanqueadores Dentales/química , Calcio/análisis , Peróxido de Hidrógeno/química , Esmalte Dental , Minerales/análisis , Minerales/farmacología , Fósforo

RESUMEN

OBJECTIVE: To evaluate if distinct 20%-22% carbamide peroxide bleaching gels present similar decomposition pattern and pH during the clinical use in both arches, as well as gels viscosity. METHODS: Participants randomly received treatments with carbamide peroxide gels (n = 10): OPF (OpalescencePF-20%); PNT (Polanight-22%); and WPC (Whiteness Perfect-22%) in three different days, with 2-day washout. Decomposition pattern was assessed by peroxide concentration. Both PC and pH of bleaching gels were measured in different time points in upper and lower trays during a total of 120 min of clinical use. Viscosity of bleaching gels was measured in triplicate. ANOVA and Tukey's test were applied (α = 0.05). RESULTS: Regarding decomposition pattern, no significant differences were observed for the interaction between gel, time, and tray position factors. The peroxide concentration progressively reduced until 120 min of trays use (p < 0.001), being overall more notable in lower trays (p < 0.001). Regarding pH, the lowest values were verified in WPC within time. At 120 min, an increase of pH was observed for both WPC and OPF (p < 0.001) compared to baseline means. PNT exhibited constant pH values over time. The values of viscosity were: OPF (1.682.000 ± 19 cP)a, WPC (1.388.667 ± 172.63 cP)ab, PNT (579.567 ± 0.98 cP)b. CONCLUSIONS: The bleaching gels presented overall decomposition pattern clinically equivalent, being more notable in lower trays over time. Nevertheless, distinct pH and viscosities were observed among the products. CLINICAL SIGNIFICANCE: Although the manufacturers recommend different times of use for bleaching gels with similar peroxide concentrations, the commercial products tested did not exhibit clinically relevant difference in the decomposition pattern during the 120 min of clinical procedure.

Asunto(s)

Blanqueadores Dentales , Blanqueamiento de Dientes , Humanos , Peróxido de Carbamida , Geles , Peróxido de Hidrógeno , Peróxidos/química , Blanqueamiento de Dientes/métodos , Blanqueadores Dentales/química , Urea/química , Estudios Cruzados

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the mineral content, expressed by calcium (Ca) and phosphate (P), in dental enamel exposed to bleaching agents using micro-computed tomography (micro-CT), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and atomic force microscopy (AFM). METHODS: Sixty bovine dental enamel specimens were randomly divided into three groups (n=20): HP35ca (bleached using 35% hydrogen peroxide with Ca); HP35wca (bleached using 35% hydrogen peroxide without Ca); and control (without bleaching). Five specimens from each group were used for SEM and EDS analyses, 10 specimens were used for AFM analysis, and the remaining five specimens were used for micro-CT analysis. The pH of the gels was measured using a pH meter. The EDS and micro-CT data were analyzed using one-way ANOVA and Pearson's correlation test. The AFM data were analyzed using one-way ANOVA (α=0.05). RESULTS: The weight percentages of Ca and P obtained using EDS were similar between the bleached and control groups. Small, superficial changes were observed by SEM in the HP35wca group. The HP35ca group showed similar patterns to the control group. AFM results showed no significant changes in the enamel roughness in any of the tested groups. No significant difference in the volume or depth of structural enamel loss was found between gels with and without Ca. No mineral loss was observed in the dentin substrate. The EDS and micro-CT analysis data exhibited a high correlation (p<0.001). CONCLUSION: The addition of Ca to the bleaching gel had no beneficial effect on the bleached tooth enamel in terms of composition, mineral loss, and surface roughness. Micro-CT results exhibited a high correlation with the EDS results.

Asunto(s)

Calcio , Esmalte Dental , Microscopía , Espectrometría por Rayos X , Blanqueadores Dentales , Microtomografía por Rayos X , Animales , Calcio/análisis , Calcio/química , Bovinos , Esmalte Dental/química , Esmalte Dental/efectos de los fármacos , Geles/química , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/farmacología , Microscopía/métodos , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Fosfatos/análisis , Distribución Aleatoria , Blanqueamiento de Dientes/métodos , Blanqueadores Dentales/química , Blanqueadores Dentales/farmacología

RESUMEN

OBJECTIVES: This study aimed to evaluate the effects of 30% hydrogen peroxide (HP) solution containing various contents of 45S5 bioactive glass (BAG) on whitening efficacy and enamel surface properties after simulating the clinical bleaching procedure. MATERIALS AND METHODS: A total of 60 bovine enamel specimens discolored with black tea were divided into five groups treated with distilled water (DW), HP, 0.01 wt.% BAG + HP, 1.0 wt.% BAG + HP, and 20.0 wt.% BAG + HP (n = 12). The pH change was observed for 20 min immediately after mixing the experimental solutions, which were applied for 20 min/week, at 37 °C over 21 days. Color, gloss, roughness, microhardness, and micromorphology measurements were conducted before and after bleaching treatment. RESULTS: All groups containing BAG experienced an increase in pH from 3.5 to 5.5 in less than 1 min, and the final pH increased as the BAG content increased. The ΔE of all experimental groups was significantly higher than that of the DW group (p < 0.05), but there were no significant differences between different BAG contents (p > 0.05). Gloss significantly decreased in all experimental groups compared to the DW group, and the increased BAG content had significantly affected the decrease in gloss (p < 0.05). There was no statistical difference in surface roughness (p > 0.05), but hardness increased significantly with BAG content after bleaching treatment (p < 0.05). CONCLUSIONS: HP containing 45S5 BAG showed efficacy in tooth whitening. Also, the pH value of the HP remained acidic near 3.5 for 20 min, while the HP containing the 45S5 BAG showed an increase in pH, which inhibited the demineralization of the enamel surface, and maintained the surface morphology. CLINICAL RELEVANCE: These novel materials are promising candidates to minimize enamel surface damage caused by HP during bleaching procedure in dental clinic.

Asunto(s)

Blanqueadores Dentales , Blanqueamiento de Dientes , Animales , Bovinos , Esmalte Dental , Dureza , Peróxido de Hidrógeno/química , Propiedades de Superficie , Blanqueamiento de Dientes/métodos , Blanqueadores Dentales/química , Blanqueadores Dentales/farmacología

RESUMEN

OBJECTIVE: To evaluate the physical-chemical (weight, pH, quantification of hydrogen peroxide) and mechanical (texture profile and rheology tests) properties of the experimental bleaching gel based on the bioadhesive polymer Aristoflex® AVC, after accelerated stability testing. MATERIALS AND METHODS: A total of 300 syringes of bleaching gels were divided into 5 groups (n = 60): Whiteness Perfect® 10%-FGM (WP); carbamide peroxide 10% with aristoflex (CPa); carbamide peroxide 10% with Carbopol (CPc); aristoflex thickener (A); and Carbopol thickener (C). According to the following requirements and time, the accelerated stability test was performed: in an incubator at 40 °C and 75% humidity per 1, 3, and 6 months, and baseline (refrigerator at 5 °C and 25% humidity). The variables were analyzed following the statistical tests: Two-way ANOVA and Tukey's test were applied to pH; weight data were analyzed using a mixed model for repeated measurements over time and the Tukey-Kramer test; one-way ANOVA and Tukey's test analyzed the rheology test; generalized linear models were used to quantify the peroxide amount and texture profile data. A significance level of 5% was considered. RESULTS: The experimental bleaches CPa and CPc had the highest pH values when compared to the others in 6 months. Thickeners A and C did not change the pH, weight, and active content over the accelerated stability times (p > 0.05). Furthermore, there was weight loss after 3 months of storage for CPa and CPc (p < 0.05). In the quantification of hydrogen peroxide, the WP group showed the highest values over time (p < 0.0001), only showing a significant loss after the 3rd month. Meanwhile, CPa and CPc showed a reduction in quantification from the 1st month. CONCLUSIONS: Temperature and humidity directly influenced the active content and properties of bleaching gels. In addition, the presence of components regardless of thickeners, such as stabilizers, in the commercial gel allowed for greater stability over time. CLINICAL RELEVANCE: The development of experimental bleaching gels for clinical use requires careful testing. Therefore, accelerated stability testing represents a valuable tool in the development and evaluation of cosmetic formulations.

Asunto(s)

Blanqueadores Dentales , Blanqueamiento de Dientes , Peróxido de Carbamida , Geles , Peróxido de Hidrógeno , Peróxidos , Polímeros , Blanqueadores Dentales/química , Urea