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1.
Braz Dent J ; 31(3): 221-235, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32667517

RESUMO

There is an increased accessibility of over-the-counter (OTC) whitening agents with very little data in the literature regarding their effectiveness. This review was done to determine their effectiveness of the predominant OTC whitening agents from 2006 until 2018 where a comparison of each agent was made with a placebo, no treatment or with other OTC whitening agents. The major categories of OTC whitening agents such as dentifrices, whitening strips and paint on gels. Dentist prescribed bleaching applied at home and in-office bleaching studies and studies that demonstrated whitening products to participants were excluded. Articles were searched for in the databases of Medline (Ovid), PubMed, the Cochrane Library and Cochrane Central Register of Controlled Trials. Twenty-four articles were included in the systematic review and the quality of studies was determined by the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) ranking criteria. Compared to other OTC, strips are reported to be effective. Two studies determined whitening strips to be effective. Whitening strips have been shown to be effective when compared with placebos and other OTC whitening agents. Dentifrices are effective in changing the shade of the tooth "by removing extrinsic stains" when compared to a placebo and non-whitening dentifrices, but they are not as effective in comparison to whitening strips. There is a lack of evidence with regards to the effectiveness of paint-on gels. While there is some evidence that OTC can alter shade in the short term, there is a need for better-designed studies.


Assuntos
Clareadores Dentários , Clareamento Dental , Descoloração de Dente , Peróxido de Carbamida , Humanos , Ureia
2.
Oral Health Prev Dent ; 18(3): 549-554, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32515427

RESUMO

PURPOSE: Resin infiltration may be a barrier for bleaching gels. The aim of this study was to compare dental bleaching effectiveness using low-concentration gels on heavily or mildly stained teeth that were or were not treated with resin infiltration agents. MATERIALS AND METHODS: Forty bovine enamel surfaces were submitted to demineralisation, after which two staining protocols were performed. Twenty specimens were immersed in a staining broth for 24 h (Lab 1) or 7 days (Lab 2). Ten specimens of each group received resin infiltrant application following the manufacturer's recommendation. All specimens were bleached using 15% carbamide peroxide gel for 14 days (8 h daily). Colour measurement was performed using a reflectance spectrophotometer at three time points: baseline, after staining, and after bleaching. Data (CIEDE00) were analysed using Student's t-test (p < 0.05). RESULTS: No statistically significant differences were observed in Lab 1 (p = 0.560). For Lab 2, statistically significant differences were detected (p = 0.031). Once bleaching was achieved to some degree (Lab 2), the resin infiltrant may have behaved as a semipermeable barrier to the carbamide peroxide gels. CONCLUSION: Bleaching treatment was effective on mildly pigmented tooth surfaces. On the other hand, in comparison to the control group, the heavily pigmented surfaces bleached less in the presence of the resin infiltrant, possibly due to the lack of free radicals penetrating into the substrate.


Assuntos
Clareadores Dentários , Clareamento Dental , Descoloração de Dente , Animais , Peróxido de Carbamida , Bovinos , Esmalte Dentário , Combinação de Medicamentos , Humanos , Resinas Vegetais
3.
J Appl Oral Sci ; 28: e20190720, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428059

RESUMO

Objective This study evaluated the clinical effect of violet LED light on in-office bleaching used alone or combined with 37% carbamide peroxide (CP) or 35% hydrogen peroxide (HP). Methodology A total of 100 patients were divided into five groups (n=20): LED, LED/CP, CP, LED/HP and HP. Colorimetric evaluation was performed using a spectrophotometer (ΔE, ΔL, Δa, Δb) and a visual shade guide (ΔSGU). Calcium (Ca)/phosphorous (P) ratio was quantified in the enamel microbiopsies. Measurements were performed at baseline (T 0 ), after bleaching (T B ) and in the 14-day follow-up (T 14 ). At each bleaching session, a visual scale determined the absolute risk (AR) and intensity of tooth sensitivity (TS). Data were evaluated by one-way (ΔE, Δa, ΔL, Δb), two-way repeated measures ANOVA (Ca/P ratio), and Tukey post-hoc tests. ΔSGU and TS were evaluated by Kruskal-Wallis and Mann-Whitney, and AR by Chi-Squared tests (a=5%). Results LED produced the lowest ΔE (p<0.05), but LED/HP promoted greater ΔE, ΔSGU and Δb (T 14 ) than HP (p<0.05). No differences were observed in ΔE and ΔSGU for LED/CP and HP groups (p>0.05). ΔL and Δa were not influenced by LED activation. After bleaching, LED/CP exhibited greater Δb than CP (p>0.05), but no differences were found between these groups at T 14 (p>0.05). LED treatment promoted the lowest risk of TS (16%), while HP promoted the highest (94.4%) (p<0.05). No statistical differences of risk of TS were found for CP (44%), LED/CP (61%) and LED/HP (88%) groups (p>0.05). No differences were found in enamel Ca/P ratio among treatments, regardless of evaluation times. Conclusions Violet LED alone produced the lowest bleaching effect, but enhanced HP bleaching results. Patients treated with LED/CP reached the same efficacy of HP, with reduced risk and intensity of tooth sensitivity and none of the bleaching protocols adversely affected enamel mineral content.


Assuntos
Peróxido de Carbamida/administração & dosagem , Peróxido de Hidrogênio/administração & dosagem , Luz , Fototerapia/métodos , Clareadores Dentários/administração & dosagem , Clareamento Dental/métodos , Adolescente , Adulto , Análise de Variância , Colorimetria , Terapia Combinada , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/efeitos da radiação , Sensibilidade da Dentina/induzido quimicamente , Feminino , Humanos , Masculino , Valores de Referência , Fatores de Risco , Espectrofotometria , Estatísticas não Paramétricas , Propriedades de Superfície/efeitos dos fármacos , Propriedades de Superfície/efeitos da radiação , Resultado do Tratamento , Adulto Jovem
4.
Oper Dent ; 45(4): 368-376, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32216723

RESUMO

CLINICAL RELEVANCE: This study suggests that at-home bleaching systems are safe in relation to toxicity based on peroxide levels in saliva since the amount of peroxide potentially ingested is much lower than the estimated toxic dose.


Assuntos
Peróxido de Hidrogênio , Clareamento Dental , Peróxido de Carbamida , Estudos Cross-Over , Combinação de Medicamentos , Géis , Peróxidos , Saliva , Ureia
5.
Quintessence Int ; 51(5): 364-371, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159531

RESUMO

The most commonly used bleaching agents contain different concentrations of hydrogen peroxide and carbamide peroxide. In the present case, the bleaching procedure was performed using an induced field of cold atmospheric plasma, obtained from dielectric barrier discharge. The therapeutic effect of the device used in the clinical procedure is based on floating electrode dielectric barrier discharge, in which the glass electrode functions as the primary electrode, while the therapeutic area, which in this case is the tooth, represents the secondary electrode. A periodontal (PA) probe is a glass tube filled with a noble gas, which generates an electrical discharge in the gap between the tip of the electrode surface and the therapeutic area, thus producing reactive oxygen species. Bleaching with only the cold atmospheric plasma bleaching technique, without any conventional bleaching agents, was performed successfully for an endodontically treated tooth. The cold atmospheric plasma bleaching technique, which could be a novel approach for the bleaching of non-vital teeth, provides good clinical results and is safe for clinical use.


Assuntos
Gases em Plasma , Clareadores Dentários , Clareamento Dental , Dente não Vital , Peróxido de Carbamida , Humanos , Peróxido de Hidrogênio , Peróxidos , Ureia
6.
Int J Esthet Dent ; 15(1): 44-54, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31994535

RESUMO

OBJECTIVE: The present study was undertaken to determine the tooth whitening effectiveness of trays with no reservoirs (Invisalign aligners or Vivera retainers used as bleaching trays), initially with a finite element analysis (FEA) and subsequently with a clinical study using spectrophotometry. MATERIALS AND METHODS: The FEA technique was used to determine the ideal distribution of bleaching gel between teeth and aligners in vitro. Three sample areas of gel application on the maxillary central incisors (the incisal edge, the middle part, and the gingival edge) were analyzed. Spectrophotometry was used to ascertain the clinical effectiveness of the bleaching gel as it related to the results of the FEA. More specifically, the chromatic variation obtained by the bleaching gel on teeth 41 and 32 (control teeth, with reservoirs) was compared with that on teeth 31 and 42 (study teeth, without reservoirs). RESULTS: The FEA results showed that the optimal gel distribution is reached when 2 mm3 of gel is applied to the center of the vestibular face of the tooth in the tray. As regards the clinical study, there were no relevant differences of whitening effectiveness between the teeth with reservoirs and those without. In both cases, the whitening was effective and the patients were completely satisfied with the results. CONCLUSIONS: The advantages for patients to receive dental bleaching during orthodontic treatment with aligners are evident. The procedure is not time consuming and requires less financial expense. Further clinical studies are required to assess the effectiveness of the procedure.


Assuntos
Clareadores Dentários , Clareamento Dental , Peróxido de Carbamida , Humanos , Peróxido de Hidrogênio , Peróxidos , Resultado do Tratamento , Ureia
7.
J Esthet Restor Dent ; 32(1): 12-18, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31904193

RESUMO

OBJECTIVE: To assess the whitening efficacy of a 16% carbamide peroxidase (CP) gel after 42 months of clinical follow-up. MATERIALS AND METHODS: A retrospective clinical study was carried out involving 95 participants. CP 16% was applied for 90 minutes a day for 4 weeks using individualized trays. Tooth color was assessed using spectrophotometry at baseline, 1 week after the end of treatment, and every 6 months until completing 42 months of follow-up. Color parameters were compared using analysis of variance for repeated measures. The analysis by teeth groups was performed using two-way ANOVA. RESULTS: The mean baseline L* was 81.7 ± 5.2 versus 83.6 ± 8.8 after 42 months (P<.01). L* showed a decrease of 2.3 after 30 months. The values corresponding to a* before treatment were 0.4 ± 1.1 versus -1.0 ± 1.0 after 42 months (P<.01). The initial values corresponding to b* were 23.4 ± 3.3 versus 15.8 ± 1.3 after 42 months (P<.01). Values of ΔE00 and ΔE, at the end of the treatment were 4.6 ± 1.2 and 7.8 ± 1.8, respectively. Teeth groups remained stable after 42 months of follow-up. CONCLUSIONS: The home application of 16% CP gel for 90 minutes a day for 4 weeks using individualized trays resulted in whitening that remained stable over the 42 months of follow-up. CLINICAL SIGNIFICANCE: Treatment with 16% CP is an effective and safe tooth whitening procedure, and the color obtained remains stable over the long term.


Assuntos
Clareadores Dentários , Clareamento Dental , Peróxido de Carbamida , Cor , Seguimentos , Peróxido de Hidrogênio , Peróxidos , Estudos Retrospectivos , Ureia
8.
Phytother Res ; 34(5): 1060-1070, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31845403

RESUMO

The aim of this study is to analyze the efficacy of natural bleaching agents and the current technological development in this research field. Two reviewers performed a literature search up to July 2019 in 15 databases. Five laboratory studies and 25 patents were included. Data regarding natural bleaching agent used, application protocol, and the main findings of studies were analyzed. Laboratory studies that evaluated natural bleaching agents' peroxide-free or associated to peroxides and patents related to natural bleaching agents were included. The studies evaluated papain, bromelain, chlorine dioxide, sodium chloride plus vinegar and sodium bicarbonate as peroxide-free agents; and sweet potato extract, lactoperoxidase, and peroxidase associated to peroxide used were included. Twenty-five patents were included; among the most cited are the papain and the chlorine. The addition of non-peroxide agents into peroxide showed improvement in bleaching effect with the incorporation of these non-peroxide agents (p < .05). On the other hand, peroxide-free agents did not show an improvement in bleaching effect (p < .05). The evidence in literature suggested that natural bleaching agents incorporated to peroxide may improve the bleaching. Therefore, the current literature does not support the use of natural agents as dental bleaching.


Assuntos
Peróxido de Carbamida/uso terapêutico , Peróxido de Hidrogênio/uso terapêutico , Clareadores Dentários/uso terapêutico , Peróxido de Carbamida/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia
9.
Braz. dent. sci ; 23(2): 1-8, 2020. tab, ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1096444

RESUMO

Objective: This study's aim was to quantify the hydrogen peroxide (HP) penetration into the pulp chamber of teeth submitted to different protocols of bleaching. Material and Methods: Ninety premolars were randomly divided into nine groups according to the bleaching agent protocol (n = 10): control (no bleaching), carbamide peroxide 10% [10% CP], carbamide peroxide 16% [16% CP], carbamide peroxide 22% [22% CP], hydrogen peroxide 4% [4% HP], hydrogen peroxide 6% [6% HP], hydrogen peroxide 7.5% [7.5% HP], hydrogen peroxide 10% [10% HP] and hydrogen peroxide 35% [35% HP]. The penetration of HP was measured via spectrophotometric analysis of the acetate buffer solution from the pulp chamber. The absorbance of the resulting solution was determined in a spectrophotometer and converted into equivalent concentration of HP (µg/ mL). To analyze the concentration of HP, the titration of bleaching agents with potassium permanganate was used. Data were subjected to ANOVA and Tukey's test for pairwise comparison (α = 0.05). Results: Higher concentration of HP in the pulp chamber was found in the HP 35% group (p < 0.0001). No significant difference between at-home protocols were observed (p = 0.64). Titration values showed that the concentration of the products was similar to that claimed by the manufacturer. Conclusion: It follows that the amount of HP that reaches the pulp chamber is not proportional to the concentration of whitening gels, but depends on the application time recommended by the manufacturers (AU)


Objetivo: o objetivo deste estudo foi quantificar a penetração do peróxido de hidrogênio (PH) na câmara pulpar dos dentes submetidos a diferentes protocolos de clareamento. Material e Métodos: Noventa pré-molares foram divididos aleatoriamente em nove grupos, de acordo com o protocolo do agente clareador (n = 10): controle (sem clareamento), peróxido de carbamida 10% [PC 10%], peróxido de carbamida 16% [PC 16%], peróxido de carbamida 22% [PC 22%], peróxido de hidrogênio 4% [PH 4%], peróxido de hidrogênio 6% [PH 6%], peróxido de hidrogênio 7,5% [PH 7,5%], peróxido de hidrogênio 10% [PH 10%] e peróxido de hidrogênio 35% [PH 35%]. A penetração de PH foi medida por análise espectrofotométrica da solução de tampão de acetato da câmara pulpar. A absorvância da solução resultante foi determinada em um espectrofotômetro e convertida em concentração equivalente de PH (µg / mL). Para analisar a concentração de PH, foi utilizada a titulação de agentes clareadores com permanganato de potássio. Os dados foram submetidos à ANOVA e teste de Tukey para comparação pareada (α = 0,05). Resultados: Foi encontrada maior concentração de PH na câmara pulpar no grupo PH 35% (p < 0,0001). Não foi observada diferença significativa entre os protocolos domiciliares (p = 0,64). Os valores de titulação mostraram que a concentração dos produtos era semelhante à reivindicada pelo fabricante. Conclusão: Conclui-se que a quantidade de PH que atinge a câmara pulpar não é proporcional à concentração de géis clareadores, porém depende do tempo de aplicação recomendado pelos fabricantes.(AU)


Assuntos
Clareamento Dental , Permeabilidade do Esmalte Dentário , Clareadores , Peróxido de Carbamida , Peróxido de Hidrogênio
10.
Dent Mater ; 35(11): 1637-1643, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31543374

RESUMO

Tooth whitening, a routine procedure in dentistry, is one of the examples of medical procedures that are limited by the challenge of delivering molecules into various types of nanoporous tissues. Current bleaching methods rely on simple diffusion of peroxides into enamel nano channels, therefore requires sufficient contact time with peroxides. In-office treatments often involve enamel etching or light activation which often results in patient sensitivity and potential soft tissue damage. OBJECTIVE: To demonstrate a robust method to transport hydrogen peroxide to greater depths into enamel nanopores through nanofluidic flows driven by electrokinetics, with the intention to increase efficacy while reducing treatment time. METHODS: Freshly extracted human teeth were subjected to electrokinetic flow treatment with hydrogen peroxide under different electric fields with varying operation times. Pre- and post-operative shade matching was done using a photospectrometer. RESULTS: It is demonstrated that the operation time for the same concentration of hydrogen peroxide can be shortened by 10 times. The proposed method showed significant improvements in whitening effects over control groups and thus offers promising clinically-viable chairside applications with efficacy. SIGNIFICANCE: The demonstrated nanofluidic transport of hydrogen peroxide into enamel has a potential to be applied for enhancing tooth whitening, compared to simple diffusion, without heating the hard dental tissues.


Assuntos
Clareamento Dental , Peróxido de Carbamida , Esmalte Dentário , Humanos , Peróxido de Hidrogênio , Peróxidos , Ureia
11.
Quintessence Int ; 50(10): 802-807, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31559399

RESUMO

Over the past decades, the walking bleach technique using sodium perborate was considered a safe and effective method to bleach nonvital discolored teeth. However, sodium perborate has been classified as carcinogenic, mutagenic, and toxic for reproduction by European Union legislation. Its use is therefore prohibited since April 2015. The initially described inside/outside bleaching technique, combining internal and external application of 10% carbamide peroxide, is an alternative to the walking bleach technique using sodium perborate. While good esthetic results and low risks of external cervical resorptions have been associated with this technique, its main drawback is that the access cavity is left open. To overcome this disadvantage, the present authors propose to seal the bleaching agent in the access cavity instead of leaving the latter open. Through a clinical case, this paper presents and discusses several aspects of this protocol, including the clinical steps, the design of the bleaching tray, and the treatment of potential recurrences. The present authors believe that the protocol proposed in this article is easier to use for the patient. Moreover, it prevents the accumulation of food debris in the access cavity and avoids the colonization of coronary dentin by bacteria.


Assuntos
Clareamento Dental , Descoloração de Dente , Dente não Vital , Peróxido de Carbamida , Humanos , Peróxido de Hidrogênio , Peróxidos , Ureia
12.
Ann Anat ; 225: 48-53, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31271888

RESUMO

OBJECTIVE: To conduct an in vitro evaluation of the effect of casein-phosphopeptide and amorphous calcium phosphate with fluoride [CPP-ACPF] upon the calcium [Ca] and phosphorus [P] composition and morphology of dental enamel and dentin after the application of two bleaching agents: 37.5% hydrogen peroxide [HP]) and 35% carbamide peroxide [CP]. MATERIALS AND METHODS: The crowns of 40 extracted human teeth were divided into four groups (n=10 each). The crowns were sectioned along the cervical-incisal axis, and each half was embedded in acrylic resin, leaving a window 3mm in diameter to explore the enamel or dentin (according to the study group involved). Groups 1a and 1b corresponded to the two halves belonging to the same tooth and were treated with HP applied to enamel three times for 10min. Afterwards, CPP-ACPF was applied in group 1b for five minutes. The same procedure was carried out in groups 2a and 2b, but application was done on dentin. Groups 3a and 3b were treated with CP applied to enamel once for 30min. Posteriorly, CPP-ACPF was applied in group 3b for five minutes. Groups 4a and 4b were treated in the same way as groups 3a and 3b, but application was done on dentin. The morphological changes were evaluated using confocal laser scanning microscopy (CLSM), and the changes in Ca and P composition were assessed by environmental scanning electron microscopy coupled to a microanalytical system (ESEM+EDX). Comparisons between groups were made using the Kruskal-Wallis test, and Duncan test was applied for two-by-two comparisons, with a significance level of p<0.05. RESULTS: Both HP and CP produced similar changes in enamel morphology and produced no changes in dentin. Groups treated with CPP-ACPF after bleaching improved the percentage of Ca and P. Statistical significance was reached only in the case of the percentage of Ca in enamel (group 1b versus group 1a, p=0.01) (group 3b versus group 3a, p=0.03). CONCLUSIONS: The application of CCP-ACPF for five minutes on the enamel surface after tooth bleaching is effective in restoring the Ca lost as a result of the bleaching process, while their effect in dentin could not be demonstrated.


Assuntos
Peróxido de Carbamida/administração & dosagem , Caseínas/administração & dosagem , Fluoretos/administração & dosagem , Peróxido de Hidrogênio/administração & dosagem , Clareamento Dental/efeitos adversos , Dente/efeitos dos fármacos , Cálcio/análise , Peróxido de Carbamida/efeitos adversos , Dentina/química , Dentina/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/efeitos adversos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Pomadas , Oxirredução , Fósforo/análise
13.
J Contemp Dent Pract ; 20(5): 587-592, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31316023

RESUMO

AIM: The aim of this study is to evaluate and compare the amount of radicular peroxide penetration when various concentrations of carbamide peroxide (CP) bleaching gels (10, 15, and 35%) and a mixture of 30% hydrogen peroxide (HP) with sodium perborate are used for intracoronal bleaching. MATERIALS AND METHODS: Fifty extracted single-rooted premolars from young adults were used. The specimens were then divided into five groups such that teeth with varying sizes were equally distributed in all groups. Group I-distilled water (control group), group II-10% CP, group III-15% CP, group IV-35% CP, and group V-30% HP with sodium perborate. Intermediate restorative material (IRM) was used to seal access cavities and left for a week at 37 °C in an incubator. Following the bleaching process, suspended teeth from plastic tubes containing distilled water were removed and the water was used to determine the amount of peroxide levels. A UV-visible spectrophotometer at a wavelength of 480 nm was used to determine the quantity of peroxide based on the optical density. RESULTS: Results showed the highest peroxide leakage in group V, followed by group IV, and then group III, whereas the least peroxide penetration was found in group II, and the control group or group I showed no penetration. The Kruskal-Wallis test showed a significant difference between the various groups tested. The Mann-Whitney test was done to find in which pair of groups there exists a significant difference. It was found that all the groups when compared among themselves showed a significant difference. CONCLUSION: The present study concluded that lower concentrations of CP 10 and 15% produced lower peroxide leakage. Hence, it could be tried as an alternate to traditional agents in cases with compromised tooth which shows cervical tooth defects where the risk of external root resorption is higher. CLINICAL SIGNIFICANCE: The management of discolored teeth involves different techniques; among various techniques, bleaching is considered to be a safe, effective, and relatively noninvasive technique to lighten discolored teeth and it also conserves dental hard tissue.


Assuntos
Clareamento Dental , Descoloração de Dente , Boratos , Peróxido de Carbamida , Géis , Humanos , Peróxido de Hidrogênio , Peróxidos , Ureia , Adulto Jovem
14.
Int J Esthet Dent ; 14(3): 324-332, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31312817

RESUMO

This in vitro study aimed to evaluate the effect of two alternative clinical protocols on the tooth bleaching effectiveness of 37% carbamide peroxide. Thirty enamel-dentin blocks from bovine incisors were stained with a coffee solution for 1 week. After color measurement at baseline with a portable spectrophotometer, the blocks were bleached during two 45-min applications of 37% carbamide peroxide with a 2-day interval between bleaching procedures, according to one of the following protocols: 1) Control: placement of bleaching agent over dried enamel; 2) Moist enamel: placement of bleaching agent over enamel previously humidified with a damp gauze for 1 min; 3) Moist cotton pellet: covering the bleaching agent with a moist cotton pellet during the entire bleaching procedure. The tooth color was assessed 2 days after each bleaching procedure. The data of ΔL, Δa, Δb, and ΔE were individually analyzed using ANOVA and Tukey's test (α = 0.05). In general, applying the bleaching agent to the moist enamel resulted in lower Δa and Δb values, and higher ΔL and ΔE values than the control. No difference was observed between the control and the protocol of covering the bleaching agent with a moist cotton pellet. Regardless of the protocol, the second bleaching procedure resulted in a further increase in ΔL and ΔE, and a reduction in Δa. A further decrease in Δb was observed only for the moist enamel protocol. In conclusion, humidifying the enamel with a damp gauze prior to the placement of 37% carbamide peroxide improved the effectiveness of the bleaching.


Assuntos
Clareadores Dentários , Clareamento Dental , Animais , Peróxido de Carbamida , Bovinos , Peróxido de Hidrogênio , Peróxidos , Ureia
15.
J Contemp Dent Pract ; 20(2): 247-257, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31058643

RESUMO

AIM: This study aimed to examine the effect of postoperative home bleaching using 20% carbamide peroxide on the shear bond strengths of different adhesives to enamel and to verify the failure mode for each test specimen. MATERIALS AND METHODS: One hundred sound human molars were used in this study. Bonding procedures were performed on the flattened buccal enamel surfaces according to the manufacturer's instructions. OptiBond Solo Plus adhesive (Kerr), Single Bond Universal adhesive (3M ESPE) applied with both the total-etch and self-etch techniques, and Tetric N-Bond Universal adhesive (Ivoclar Vivadent) applied with both the total-etch and self-etch techniques were used, followed by resin composite post fabrication (Filtek Z350 XT; 3M ESPE). All specimens were thermo-cycled for 5000 cycles and then divided into the control (non-bleach) and postoperative bleaching groups (20% carbamide peroxide). The shear bond strength values were measured and compared between the two groups. Data were analyzed using one-way analysis of variance with Tukey's test (p = 0.05). The failure modes of debonded specimens were evaluated using a digital microscope (50×). The bonding interfaces of the resin composite posts to different enamel conditions (control and postoperative bleaching) were observed by a scanning electron microscope (SEM) before the shear bond test. RESULTS: The shear bond strength values of all tested adhesives were lower in the postoperative bleaching group than they were in the control (non-bleach) group, particularly the bond strength values of self-etch adhesives. CONCLUSION: The stability of bonded resin composite restorations to enamel, using different dental adhesives, could be compromised after the bleaching procedure at varying sensitivity levels. CLINICAL SIGNIFICANCE: Replacement of bonded resin composite restorations to enamel might be considered after bleaching procedures, especially if these restorations were previously bonded with self-etch adhesives.


Assuntos
Peróxido de Carbamida , Colagem Dentária , Resinas Compostas , Esmalte Dentário , Adesivos Dentinários , Humanos , Teste de Materiais , Peróxidos , Cimentos de Resina , Resistência ao Cisalhamento , Ureia
16.
Photodiagnosis Photodyn Ther ; 27: 59-65, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31121330

RESUMO

BACKGROUND: The aim of this study was to analyze bleaching treatment performed with different products, with or without the use of Violet LED. METHODS: The color and dental sensitivity of six patients were evaluated as follows: (1)at-home bleaching with 10% Carbamide Peroxide (CP); (2)in-office bleaching with 17.5% Hydrogen Peroxide (HP), and (3)treatment with a placebo gel. All patients, including patients receiving at-home bleaching, received irradiation with violet LED in the office. The right hemiarch was protect with silicone. The color was evaluated using Vita Easyshade digital spectrophotometer and the Vita scale on teeth 13-23. Visual analog scale sensitivity analysis was performed per hemiarch, while the thermal sensation threshold was performed on teeth 11, 13, 21 and 23. RESULTS: Regarding the color change (ΔE) it can be observed that treatment 1, in which 10%CP was used, presented the highest values, followed by treatment 2, in which 17.5%HP was used. Regarding sensitivity, only patients who received 17.5%HP showed moderate sensitivity, and there was no difference between the arches. The analysis of dental thermal sensation threshold showed that there was more dental sensitization between 7 and 14 days and that the use of violet LED made the teeth more sensitive. CONCLUSIONS: It was concluded that violet LED enhanced the bleaching effect when used with 10%PC gels, and a discreet effect was seen when used either in conjunction with 17.5%PH or alone. Violet LED had no effect on pain sensation, but increased the detection threshold of thermal changes in the teeth that were irradiated.


Assuntos
Peróxido de Carbamida/uso terapêutico , Peróxido de Hidrogênio/uso terapêutico , Fotoquimioterapia/métodos , Clareadores Dentários/uso terapêutico , Clareamento Dental/métodos , Adulto , Peróxido de Carbamida/efeitos adversos , Sensibilidade da Dentina/induzido quimicamente , Relação Dose-Resposta a Droga , Feminino , Humanos , Peróxido de Hidrogênio/efeitos adversos , Luz , Masculino , Fotoquimioterapia/efeitos adversos , Clareamento Dental/efeitos adversos , Clareadores Dentários/efeitos adversos , Adulto Jovem
17.
Colloids Surf B Biointerfaces ; 179: 326-333, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30981068

RESUMO

Carbamide peroxide is the popular home dental whitening agent. However, it has critical stability. Nanoparticles have been applied to develop products with advantages properties as better efficacy and stability increase. The aim of this study was the characterization of carbamide peroxide polymeric nanoparticles, their bleaching efficacy, effects on pulp damage and stability evaluation. Particle size demonstrated a spherical morphology and bimodal distribution (11 and 398 nm). Nanoparticles presented high entrapment efficiency (98.94%) and the zeta potential value was slightly positive (+10.26 mV). Regardless of the zeta potential, the steric effect may contribute to carbamide peroxide nanoparticle stabilization. The stability studies conducted at room temperature suggested that carbamide peroxide nanoparticles could maintain all the parameters evaluated (size, polydispersity index, zeta potential, entrapment efficiency, pH and content) for at least 90 days. Instability index was determined by dispersion analyzer (LUMiSizer ®), was 0.018, and the light transmission profile did not present sedimentation. Carbamide peroxide nanoparticles were able to prevent thermal degradation and photostability. Clinical efficacy of the whitening gels was obtained by color change in the spectrophotometer and the results showed that all the evaluated gels containing the nanoparticles (0, 1, 2 and 5% of real carbamide peroxide) were effective at bleaching after 2 h of home whitening treatment (during 30 days). After the treatment, the extracted teeth showed no in situ pulp damage by histological evaluation. The nanotechnology strategy of converting carbamide peroxide into polymeric nanoparticles revealed a new product with improved stability, a good approach for carbamide peroxide delivery.


Assuntos
Peróxido de Carbamida/farmacologia , Nanopartículas/química , Clareamento Dental , Polpa Dentária/efeitos dos fármacos , Nanopartículas/ultraestrutura , Temperatura
18.
J Appl Oral Sci ; 27: e20180442, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30994776

RESUMO

OBJECTIVE: To assess pulp oxygen saturation levels (SaO2) in maxillary central incisors after dental bleaching. MATERIALS AND METHODS: 80 participants (160 teeth) were randomly allocated to four groups: G1 In-office bleaching with two applications of 35% hydrogen peroxide (HP) (20 minutes), followed by at-home bleaching with 10% carbamide peroxide (CP) (2 hours/day for 16 days); G2 - Same protocol as G1, plus desensitizing toothpaste; G3 - In-office bleaching with 35% HP and one application of placebo gel (20 minutes), followed by at-home bleaching with 10% CP (2 hours/day for 16 days); and G4 - Same protocol as G3, plus desensitizing toothpaste. Pulp SaO2 levels were measured before (T0) and immediately after (T1) in-office bleaching; on the 5th (T2), 8th (T3), 12th (T4), and 16th days of at-home bleaching (T5); and on the 7th (T6) and 30th (T7) days. Mean (SD) pulp SaO2 levels were compared within groups by generalized estimating equations (GEE) and Student's t-test (P<0.05). RESULTS: Mean pulp SaO2 at T0 was 84.29% in G1, 84.38% in G2, 84.79% in G3, and 85.83% in G4. At T1, these values decreased to 81.96%, 82.06%, 82.19%, and 81.15% in G1, G2, G3, and G4 respectively, with significant difference in G4 (P<0.05). During home bleaching, pulp SaO2 levels varied in all groups, with 86.55%, 86.60%, 85.71%, and 87.15% means at T7 for G1, G2, G3, and G4, respectively; G2 presented significant difference (P<0.05). CONCLUSIONS: Pulp SaO2 level in maxillary central incisors was similar at baseline, reducing immediately after in-office bleaching, regardless of using desensitizing toothpaste and increasing at 30 days after dental bleaching.


Assuntos
Polpa Dentária/metabolismo , Incisivo/metabolismo , Oxigênio/metabolismo , Clareadores Dentários/efeitos adversos , Clareamento Dental/efeitos adversos , Adolescente , Adulto , Peróxido de Carbamida/efeitos adversos , Polpa Dentária/efeitos dos fármacos , Dessensibilizantes Dentinários/uso terapêutico , Sensibilidade da Dentina/induzido quimicamente , Sensibilidade da Dentina/prevenção & controle , Feminino , Humanos , Peróxido de Hidrogênio/efeitos adversos , Incisivo/efeitos dos fármacos , Masculino , Oximetria/métodos , Valores de Referência , Fatores de Tempo , Clareamento Dental/métodos , Cremes Dentais/uso terapêutico , Resultado do Tratamento , Adulto Jovem
19.
Environ Sci Pollut Res Int ; 26(17): 17427-17437, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31016589

RESUMO

Previous studies have demonstrated the side effects of tooth whiteners on the gastric mucosa. However, the impact of dental bleaching products on the liver, kidney, and heart remains obscure. The present study investigated the toxic potential of 35% carbamide peroxide (CPO) containing tooth whitening product (TWP) on the liver, kidney, heart, and stomach of mice, pointing to the role of oxidative stress and inflammation. Mice received 250 or 500 mg/kg body weight CPO-TWP orally for 3 weeks and samples were collected for analyses. Both doses of CPO-TWP induced a significant increase in circulating liver, kidney, and heart function markers. CPO-TWP-administered mice showed several histological alterations and a significant increase in liver, kidney, heart, and stomach lipid peroxidation levels along with diminished glutathione, superoxide dismutase, and catalase. In addition, administration of CPO-TWP provoked anemia, leukocytosis, and a significant increase in circulating levels of pro-inflammatory cytokines. In conclusion, exposure to 35% CPO-TWP induced functional, histological, and hematological alterations, oxidative stress, and inflammation in mice. Therefore, the frequent use of tooth bleaching agents should be monitored very carefully to avoid the application of excess amounts as well as the intake.


Assuntos
Peróxido de Carbamida/toxicidade , Clareadores Dentários/toxicidade , Clareamento Dental/métodos , Animais , Combinação de Medicamentos , Humanos , Peróxido de Hidrogênio , Inflamação/induzido quimicamente , Rim , Fígado , Masculino , Camundongos , Estresse Oxidativo/fisiologia , Peróxidos , Testes de Toxicidade Crônica , Ureia
20.
PLoS One ; 14(4): e0214948, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30951549

RESUMO

This work aimed to evaluate the roughness, microhardness, ultrastructure, chemical composition and crystalline structure in submitted teeth to a prolonged home bleaching regimen with 10% carbamide peroxide (10% PC) for different periods. The specimens were divided into the following groups: G1: negative control (application of water-soluble gel); G2: tooth whitening group (positive control), under application time recommended by the manufacturer (4h/14 days); G3: prolonged whitening 50%, under prolonged time recommended by the manufacturer in 50% (4h/21 days); G4: excessive whitening 100%, under exceeded manufacturer recommended time by 100% (4h/ 28 days). The results were evaluated descriptively and analytically. There were no changes in the roughness in any of the evaluated groups. However, the microhardness decreased in the G4 group. Scanning electron microscopy showed changes in the enamel surface of groups G2, G3 and G4. Dispersive X-ray spectroscopy identified changes in the concentration of chemical elements O, Mg, P, K in all groups. Thus, this study showed that prolonged home bleaching could cause changes in the ultrastructure, chemical composition and microhardness of the enamel.


Assuntos
Peróxido de Carbamida/farmacologia , Esmalte Dentário , Dureza/efeitos dos fármacos , Clareamento Dental , Animais , Bovinos , Esmalte Dentário/metabolismo , Esmalte Dentário/ultraestrutura , Microscopia Eletrônica de Varredura , Propriedades de Superfície/efeitos dos fármacos
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