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J Esthet Restor Dent ; 33(8): 1175-1185, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34453873


OBJECTIVE: To compare at-home systems with reduced daily time of use (10% hydrogen peroxide [HP] gel with prefilled (PT) or customized trays (CT), and 10% carbamide peroxide [CP] gel), with the conventional nightguard vital bleaching (10% CP). Bleaching efficacy, adverse effects, and patient's satisfaction were evaluated. METHODS: Sixty participants were randomly divided into treatments (14 days): Opalescence GO (OGO)-10%HP PT-30 min, White Class-10%HP CT-30 min, Opalescence PF-10%CP CT-2 h, and Opalescence PF-10%CP CT-8 h. Color difference (visual and spectrophotometer), tooth sensitivity (visual analogue scale), gingival condition (Löe index), enamel mineralization (laser fluorescence), and patients' satisfaction (questionnaire) were assessed. Statistical tests were applied (5%). RESULTS: After 1 year, color difference was similar for the groups (p > 0.05). All groups showed similar sensitivity risk (p > 0.05). The intensity of sensitivity and gingival irritation was mild for all gels, but higher for OGO. Fluorescence after bleaching remained similar to those of sound enamel. All participants were satisfied with treatments. CONCLUSIONS: All systems produced similar bleaching efficacy, which was maintained after 1 year. Patients were satisfied with bleaching outcomes. Tooth sensitivity occurred in all groups, but with overall mild intensity. No relevant gingival irritation and enamel demineralization was observed. CLINICAL SIGNIFICANCE: Bleaching with 10% HP gels in prefilled and CTs represent efficacious alternative for tooth color change, with patients' acceptance similar to conventional 10% CP. Patients must be warned about the mild sensitivity and gingival irritation potential, mainly with PTs.

Acta odontol. latinoam ; 34(1): 10-17, Apr. 2021. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1284929


ABSTRACT Dentin hypersensitivity is caused by increased dentinal permeability due to total or partial exposure of dentinal tubules, which in turn can be produced by alterations of dental structures or failure of restorative procedures. The purpose of this in vitro study was to evaluate the efficacy of the application of different kinds of adhesive systems to prevent dentin permeability before and after an erosive challenge. Fifty bovine dentin discs (6x1 mm) were prepared and the specimens were divided into 5 groups (n=10): (SB2) Single Bond 2, (SBU) Universal Single Bond, (CSB) Clearfil SE Bond, (SM) Scotchbond Multipurpose and (C) Control. Hydraulic conductance of dentin was recorded after adhesive application (HC-1) and after erosive challenge (HC-2). Dentin surface images of post-treatment and post-erosive challenge were obtained by scanning electron microscopy (SEM). Data were analyzed using Kruskal Wallis, Mann-Whitney with Bonferroni correction and Wilcoxon tests (p<0.05). Reduction in dentin permeability was observed with the application of adhesive systems (p<0.05). After the erosive challenge, dentin permeability increased for SBU and CSB (p<0.05), while SB2 and SM did not differ in HC-1 or HC-2 (p>0.05). The conventional, self-etching and universal adhesive systems reduce dentinal permeability by more than 80%, and dentin demineralization may contribute to the increased permeability of universal and self-etching systems.

RESUMO Diversos pacientes apresentam hipersensibilidade dentaria ou falha nos procedimentos restauradores, devido á exposigao total ou parcial de túbulos dentinários. O objetivo deste estudo in vitro foi o de avaliar a influencia da aplicagao de diferentes tipos de sistemas adesivos na permeabilidade da dentina e após o desafio erosivo. Cinquenta discos de dentina bovina (6x1 mm) foram confeccionados e os espécimes foram divididos em 5 grupos (n = 10): (SB2) Single Bond 2, (SBU) Universal Single Bond, (CSB) Clearfil SE Bond, (SM) ScotchbondMultiuso e (C) Controle. A condutáncia hidráulica da dentina foi registrada após a aplicagao do adesivo (HC-1) e após o desafio erosivo (HC-2). Imagens da superficie da dentina de pós-tratamento e pós-desafio erosivo foram obtidas por microscopia eletronica de varredura (MEV). Os dados foram analisados pelos testes de Kruskal Wallis, Mann-Whitney com correçâo de Bonferroni e Wilcoxon (p <0,05). Reduçâo da permeabilidade dentinária foi observada com a aplicaçâo dos sistemas adesivos (p <0,05). Após o desafio erosivo, a permeabilidade dentinária aumentou para SBU e CSB (p <0,05), enquanto SB2 e SM nao diferiram em HC-1 e HC-2 (p> 0,05). Os sistemas adesivos convencionais, autocondicionantes e universais reduzem a permeabilidade dentinária em mais de 80%, e a dentina desmineralizada pode gerar um aumento da permeabilidade dos sistemas adesivos universais e autocondicionantes.

ScientificWorldJournal ; 2013: 193241, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24163616


This study evaluated the effect of physical and chemical activation on the diffusion time of different concentrations of hydrogen peroxide (HP) bleaching agents through enamel and dentin. One hundred and twenty bovine cylindrical specimens were divided into six groups (n = 20): 20% HP; 20% HP with light activation; 20% HP with manganese gluconate; 35% HP; 35% HP with light activation; and 35% HP with manganese gluconate. The specimens were fixed over transparent epoxy wells with internal cavities to simulate a pulpal chamber. This chamber was filled with an enzymatic reagent to simulate pulpal fluid. The bleaching gels were applied on enamel surface and the image of the pulpal fluid was captured by a video camera to monitor the time of peroxide penetration in each specimen. ANOVA analysis showed that concentration and type of activation of bleaching gel significantly influenced the diffusion time of HP (P < 0.05). 35% HP showed the lowest diffusion times compared to the groups with 20% HP gel. The light activation of HP decreased significantly the diffusion time compared to chemical activation. The highest diffusion time was obtained with 20% HP chemically activated. The diffusion time of HP was dependent on activation and concentration of HP. The higher concentration of HP diffused through dental tissues more quickly.

Peróxido de Hidrogênio/química , Animais , Bovinos , Esmalte Dentário/química , Dentina/química
J Dent ; 41(3): 278-86, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23207519


OBJECTIVES: To evaluate the effects of surface treatment, surface hydration (SH) and application method (AM) on the tensile bond strength of the Silorane Adhesive System (SAS) to dentine. METHODS: Ninety bovine teeth were used. For the control group (n=10), each dentine surface was treated according to the manufacturer's instructions of the SAS. The remaining teeth were randomly distributed into two groups (n=40), according to the type of dentine surface treatment (ST)-37% phosphoric acid or Er:YAG Laser prior to the application of the SAS. Each group was further divided into 2 subgroups (n=20), according to the SH status: dry (D) or wet (W). Each subgroup was further divided into 2 subgroups (n=10), according to the application method [AM: Active (AC) mode or Passive (PA) mode]. A coat of resin composite (Filtek P90) was applied on the surface. Artificial ageing was performed with a thermo-mechanical cycling machine. The specimens were sectioned into 1mm×1mm×10mm sticks and stressed to failure using a universal testing machine. The remaining teeth in each group were used for Scanning Electron Microscopy to examine the fractured area. Data were subjected to a three-way ANOVA, Tukey's test and Dunnet's test (α=0.05). RESULTS: The ANOVA showed significant differences for SH and AM, but not for ST. For SH, the results of Tukey's test were (in MPa): D - 14.9(±3.8)(a), W - 17.1(±4.3)(b); and for AM: PA - 14. 9(±4.2)(a), AC - 17.1(±3.9)(b). CONCLUSIONS: Acid etching, when combined with a moist dentine surface and the use of primer agitation, improves the bond strength of the SAS to dentine. CLINICAL SIGNIFICANCE: According to the results of the present in vitro study, modification of the application protocols for the silorane-based adhesive system may improve its clinical performance.

Colagem Dentária/métodos , Corrosão Dentária/métodos , Adesivos Dentinários/química , Dentina , Resinas de Silorano , Animais , Bovinos , Resinas Compostas , Corrosão Dentária/instrumentação , Análise do Estresse Dentário , Lasers de Estado Sólido , Microscopia Eletrônica de Varredura , Ácidos Fosfóricos , Distribuição Aleatória , Resistência à Tração , Vibração , Molhabilidade , Agentes Molhantes
Int J Dent ; 2012: 347848, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23193404


This in vitro study evaluated the effect of 35% hydrogen peroxide (HP) bleaching gel modified or not by the addition of calcium and fluoride on enamel susceptibility to erosion. Bovine enamel samples (3 mm in diameter) were divided into four groups (n = 15) according to the bleaching agent: control-without bleaching (C); 35% hydrogen peroxide (HP); 35% HP with the addition of 2% calcium gluconate (HP + Ca); 35% HP with the addition of 0.6% sodium fluoride (HP + F). The bleaching gels were applied on the enamel surface for 40 min, and the specimens were subjected to erosive challenge with Sprite Zero and remineralization with artificial saliva for 5 days. Enamel wear was assessed using profilometry. The data were analyzed by ANOVA/ Tukey's test (P < 0.05). There were significant differences among the groups (P = 0.009). The most enamel wear was seen for C (3.37 ± 0.80 µm), followed by HP (2.89 ± 0.98 µm) and HP + F (2.72 ± 0.64 µm). HP + Ca (2.31 ± 0.92 µm) was the only group able to significantly reduce enamel erosion compared to C. The application of HP bleaching agent did not increase the enamel susceptibility to erosion. However, the addition of calcium gluconate to the HP gel resulted in reduced susceptibility of the enamel to erosion.

Acta Odontol Scand ; 70(2): 122-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21780968


OBJECTIVE: The aim of this study was to assess the enamel microhardness treated with three in-office bleaching agents, containing 35% hydrogen peroxide with different acidity. MATERIALS AND METHODS: Bovine incisors were divided into three groups that received the following bleaching agents: Whiteness HP, Total Bleach and Opalescence Xtra. Three gel applications/10-min each, totaling 30-min of bleaching treatment, were made on the teeth and activated with a blue LED (1000 mW/470 nm) combined to a LASER (120 mW/795 nm) device (Easy Bleach-Clean Line). Vickers hardness (VH) was evaluated at baseline and after the bleaching procedure. The values of Hardness loss [HNL] (% reduction) were calculated. The two-sample t-test was used for comparison of the HNL of the three bleaching products (5% level of significance). RESULTS: The Opalescence Xtra, which had the lowest pH value (pH = 4.30), showed a significant increase of HNL when compared with Total Bleach bleaching agent, which had the highest pH value (pH = 6.62). CONCLUSIONS: The 35% hydrogen peroxide bleaching agents resulted in a reduction in surface enamel microhardness and bleaching with the most acid agent resulted in a significant enamel hardness loss compared to the less acid agent (4.30 vs 6.62). Strategies proposed to reduce the enamel loss after bleaching treatment may include the use of daily fluoride therapy, mouth rinsing (fluoride, milk and sodium bicarbonate solution), fluoride/bicarbonate dentifrices without abrasives, do not toothbrush immediately after bleaching, fluorides and calcium add to bleaching agents.

Esmalte Dentário/efeitos dos fármacos , Dureza/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Clareamento Dental/efeitos adversos , Ácidos/química , Animais , Bovinos , Relação Dose-Resposta a Droga , Peróxido de Hidrogênio/administração & dosagem , Concentração de Íons de Hidrogênio , Desmineralização do Dente/induzido quimicamente
Oper Dent ; 36(2): 162-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21777098


The aim of this study was to assess the influence of manganese gluconate, a chemical activator of bleaching agents, at a concentration of 0.01% on the efficiency of a 10% carbamide peroxide-based bleaching agent. Forty bovine incisors were immersed in a 25% instant coffee solution for seven days and randomly divided into two groups. Group 1 was the control group and consisted of 10% carbamide peroxide-based bleaching gel only. Group 2 consisted of 10% carbamide peroxide-based bleaching gel and 0.01% manganese gluconate. Three readings of color were taken using the Vita Easyshade spectrophotometer: the initial reading, a reading at seven days, and a reading at 14 days. Total color variation was calculated by ΔE*Lab. Data were submitted to the statistical t-test (5%), which showed that after seven days group 2 had a significant increase in the degree of tooth bleaching compared with group 1. The mean values (±SD) were 16.33 (±3.95) for group 1 and 19.29 (±4.97) for group 2. However, the results for group 1 and group 2 were similar after 14 days. Adding 0.01% manganese gluconate to 10% carbamide peroxide bleaching gel increased the degree of tooth bleaching after a seven-day treatment and did not influence the resulting shade after 14 days.

Gluconatos/uso terapêutico , Peróxidos/uso terapêutico , Clareadores Dentários/uso terapêutico , Clareamento Dental/métodos , Ureia/análogos & derivados , Animais , Peróxido de Carbamida , Bovinos , Café , Cor , Esmalte Dentário/efeitos dos fármacos , Sinergismo Farmacológico , Teste de Materiais , Distribuição Aleatória , Espectrofotometria , Fatores de Tempo , Descoloração de Dente/tratamento farmacológico , Ureia/uso terapêutico
Acta odontol. venez ; 49(3)2011. tab, graf
Artigo em Espanhol | LILACS | ID: lil-678838


El objetivo de este estudio fue evaluar tres métodos de pulimento de las superficies de una porcelana con la finalidad de producir superficies con menor rugosidad. Fueron confeccionados 40 especímenes en formato cilindros estandarizados de 5mm de diámetro y 2mm de altura con la porcelana IPS Empress 2. Posteriormente los especímenes fueron divididos en grupos y sus superficies fueron sometidos a técnicas de pulido diferentes. Cada espécimen fue analizado en el rugosímetro, y en cada espécimen se realizó tres mediciones a lo largo de su eje, dando como resultado la rugosidad promedio (Ra). Las medias de Ra fueron sometidas a los tests estadísticos de Anova y Tukey (p? 0,05). El Grupo A (Control - Glaseado) presentó la menor media de Ra (A=0,9190) que los demás grupos (B =2,879; C=2,897; D =3,468). En base a los datos obtenidos por este estudio se puede inferir que los sistemas de pulimento disminuyen la rugosidad superficial provocada por el ajuste oclusal en las cerámicas odontológicas. Entre tanto, esos conjuntos son incapaces de devolver la vitrificación de la superficie

The aim of this study was to evaluate three porcelain polishing systems used to raise smoother surfaces. 40 IPS Empress 2 cilindric specimens with 5mm of diameter and 2mm height. The specimens were divided in groups and polished with different systems. Each specimen has his surface by a perfilometer three times resulting the mean roughness of each specimen (Ra). The Ra mean was submitted to ANOVA and Tukey´s tests (p? 0,05). For the group A (Control - Glaze) was found smaller mean values of Ra (A=0,9190) compared to the other groups (B =2,879; C=2,897; D =3,468). Based on these results we´re able to imply that the used polishing systems reduces the surface roughness caused by occlusal adjustment. However the polishing systems are unable to restore the smoothness provided by the glaze

Ligas Dentárias , Porcelana Dentária , Polimento Dentário/instrumentação , Estética Dentária
J Oral Sci ; 51(4): 593-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20032613


The aim of this study was to investigate the apical leakage of roots filled by three different gutta-percha techniques: lateral condensation, Tagger's hybrid and E&Q Master. Forty-two extracted single-rooted teeth were used. The coronal part of each tooth was removed and the root received biomechanical preparation using a 60-K file. The roots were randomly divided into three groups according to the technique of filling the root canal: Group I, lateral condensation; Group II, Tagger's hybrid; Group III, E&Q Master. The roots were submitted to dye leakage test with Rhodamine B for 7 days, using vacuum during the initial 30 min. The teeth were sectioned longitudinally and the leakage was measured in a linear fashion from apex to crown. Statistical analysis indicated that lateral condensation and E&Q Master techniques showed lower leakage than Tagger's technique (P = 0.0016). However, statistically no difference was found between lateral condensation and E&Q Master system techniques.

Infiltração Dentária/prevenção & controle , Obturação do Canal Radicular/métodos , Adolescente , Adulto , Corantes , Infiltração Dentária/diagnóstico , Resinas Epóxi , Guta-Percha , Humanos , Incisivo , Materiais Restauradores do Canal Radicular , Ápice Dentário , Adulto Jovem