One-year clinical observation of the effect of internal bleaching on pulpless discolored teeth / 华西口腔医学杂志

OBJECTIVES@#This study aimed to observe the color rebound and rebound rates of non-pulp discolored teeth within 1 year after routine internal bleaching to guide clinical practice and prompt prognosis.@*METHODS@#In this work, the efficacy of bleaching was observed in 20 patients. The color of discolored teeth was measured by using a computerized colorimeter before bleaching; immediately after bleaching; and at the 1st, 3rd, 6th, 9th, and 12th months after bleaching. The L*, a*, and b* values of the color of cervical, mesial, and incisal parts of the teeth were obtained, and the color change amounts ΔE*, ΔL*, Δa*, and Δb* were calculated. The overall rebound rate (P*) and the color rebound velocity (V*) were also analyzed over time.@*RESULTS@#In 20 patients following treatment, the average ΔE* of tooth color change was 14.99. After bleaching, the neck and middle of the teeth ΔE* and ΔL* decreased in the 1st, 3rd, 6th, 9th, and 12th months, and the differences were statistically significant. Meanwhile, from the 9th month after bleaching, the rebound speed was lower than that in the 1st month, and the difference was statistically significant. The incisal end of the tooth ΔE* and ΔL* decreased in the 6th, 9th, and 12th months after bleaching, and the differences were statistically significant. No significant difference was found in the rebound speed between time points. However, this rate settled after the 9th month, with an average color rebound rate of 30.11% in 20 patients.@*CONCLUSIONS@#The results indicated that internal bleaching could cause a noticeable color change on pulpless teeth. The color rebound after bleaching was mainly caused by lightness (L*), which gradually decreased with time, and it was slightly related to a* and b*. The color of the teeth after internal bleaching rebounded to a certain extent with time, but the color rebound speed became stable from the 9th month. Clinically, secondary internal bleaching can be considered at this time according to whether the colors of the affected tooth and the adjacent tooth are coordinated and depending on the patient's needs.

Efeitos do uso de produtos clareadores de autoaplicação sobre a superfície de uma resina composta nanoparticulada / The effects of over-the-counter bleaching products on the surface of nanofilled composite

Objetivo: Avaliar a alteração da rugosidade superficial de uma resina composta nanoparticulada (Filtek Z350 XT ® ) após o uso de produtos clareadores de autoaplicação contento baixa concentração de peróxido de hidrogênio. Métodos: Para isto, foram confeccionados 30 corpos de prova deste material, divididos aleatoriamente em 3 grupos com 10 amostras cada, da seguinte forma: G1 (grupo controle) no qual as amostras não foram submetidas à ação de nenhum produto clareador; G2, realização de procedimento clareador com peróxido de hidrogênio a 10% (Crest 3D White Professional Effects Whitestrips ® ) em 2 aplicações de 30 minutos, por 10 dias consecutivos; e G3, tratamento com peróxido de hidrogênio a 7,7% (pincel Pretty Smile ® ) com o mesmo número de aplicações, tempo e dias do G2. Após este período cada corpo de prova foi analisado no rugosímetro Surftest SJ-301, para determinar a sua rugosidade superficial média. Estes dados foram então submetidos à análise estatística por meio da análise de variância (ANOVA) e teste de Tukey, nível de significância de 5% para comparações múltiplas. Resultados: Ao final do experimento, houve diferenças estatísticas significantes entre o grupo controle (G1) e os demais grupos (G2 e G3), com p < 0,05. Porém, quando analisados apenas os grupos submetidos ao clareamento com o peróxido de hidrogênio em diferentes concentrações (G2 e G3), não foi encontrada diferença significativa (p > 0,05). Conclusão: Após 10 dias, os produtos clareadores testados determinaram aumento significativo nos valores de rugosidade superficial média da resina composta nanoparticulada.

Aim: Tod evaluate the change in surface roughness of a nanoparticulate composite resin (Filtek Z350 XT ® ) after using over-the-counter bleaching products, containing a low concentration of hydrogen peroxide. Methods: For this, 30 specimens of this material were made, randomly divided into 3 groups with 10 samples each, as follows: G1 (control group) in which the samples were not subjected to the action of any bleaching product; G2, performing a bleaching procedure with 10% hydrogen peroxide (Crest 3D White Professional Effects Whitestrips ® ), in 2 applications of 30 minutes, for 10 consecutive days; and G3, treatment with 7.7% hydrogen peroxide (Pretty Smile ® ), with the same number of applications, time, and days as G2. After this period, each specimen was analyzed, using the Surftest SJ-301, to determine its average surface roughness. These data were then subjected to statistical analysis through analysis of variance (ANOVA) and Tukey's Test, with a significance level of 5% for multiple comparisons. Results: Statistically significant differences were found between the control group (G1) and the other groups (G2 and G3), with p < 0.05. However, when analyzing only the groups submitted to bleaching agents with hydrogen peroxide in different concentrations (G2 and G3), no significant difference was found (p > 0.05). Conclusions: After 10 days, the bleaching products tested in this study determined a significant increase in the average surface roughness values of the nanoparticulate composite resin.

Aclaramiento Dental con Enjuagues de Libre Venta que Contienen Peróxido de Hidrógeno / Toothbleaching with over the Counter Mouthwashes Containing Hydrogen Peroxide

RESUMEN: El objetivo de este estudio in vitro fue evaluar la eficacia en el aclaramiento dental de tres enjuagues orales que contienen peróxido de hidrógeno en diferentes períodos de inmersión en comparación con el peróxido de carbamida al 10 %. Cuarenta muestras de premolares humanos se dividieron aleatoriamente en cuatro grupos según el agente al que se expuso: G1: Colgate Plax®Whitening, G2: Listerine®Whitening Extreme y G3: Oral B® 3D White™ se sumergieron dos minutos al día durante 28 días y G4: Peróxido de carbamida al 10 %, ocho horas al día durante 14 días. La medición de color se realizó con un espectrofotómetro Vita Easyshade usando la escala CIELab inicialmente, a los 14, 28 y 35 días de evaluación. Las comparaciones entre los grupos se realizaron utilizando las pruebas Kruskal-Wallis y U Mann-Whitney, mientras que entre los tiempos las pruebas Friedman y Signo-Rango de Wilcoxon. Los resultados revelaron que a los 14 días, los cuatro grupos mostraron cambios de color, pero no se evidenció mayor eficacia de alguno sobre el otro (p>0,05). Sin embargo, a los 28 y 35 días se observó una clara eficacia del peróxido de carbamida sobre los enjuagues (p<0,05). Los enjuagatorios orales aclaran los dientes a partir de los 28 días, con los protocolos indicados; sin embargo no llegan a tener resultados similares a un aclaramiento profesional con gel de peróxido de carbamida al 10 %.

ABSTRACT: The objective of this in vitro study was to evaluate the efficacy in dental toothbleaching of three mouthwashes containing hydrogen peroxide in different periods of immersion compared to 10 % carbamide peroxide. Forty samples of human premolars were randomly divided into four groups according to the agent to which they were exposed: G1: Colgate Plax®Whitening, G2: Listerine®Whitening Extreme and G3: Oral B® 3D White ™ were immersed two minutes a day during 28 days and G4: 10 % carbamide peroxide, eight hours a day for 14 days. The color measurement was performed with a Vita Easyshade spectrophotometer using the CIELab scale initially, at 14, 28 and 35 days of evaluation. The comparisons between the groups were made using the Kruskal-Wallis and U Mann-Whitney tests. While between the times the tests Friedman and Sign-Range of Wilcoxon. The results revealed that at 14 days, the four groups showed color changes, but no greater effectiveness was shown of one over the other (p>0,05). However, at 28 and 35 days a clear efficacy of carbamide peroxide was observed on the rinses (p<0,05). Mouthwashes clear the teeth after 28 days, with the indicated protocols; however, they do not reach similar results to a professional clarification with 10 % carbamide peroxide gel.

Effectiveness of a new non-hydrogen peroxide bleaching agent after single use - a double-blind placebo-controlled short-term study

Abstract Tooth whitening represents perhaps the most common aesthetic procedure in dentistry worldwide. The efficacy of bleaching depends on three aspects: bleaching agent, bleaching method, and tooth color. Objective: This in vivo study aimed to examine whitening effects on frontal teeth of the upper and lower jaws using an over-the-counter (OTC) non-hydrogen peroxide bleaching agent in comparison to a placebo after one single use. Material and methods: Forty subjects (25 female; 15 male) participated in this double-blind randomized placebo-controlled trial. The subjects were randomly allocated to two groups (n=20). The test group received the OTC product (iWhite Instant) and the placebo group received an identically composed product except for the active agents. Each subject was treated with a prefilled tray containing iWhite Instant or the placebo for 20 minutes. The tooth shade of the front teeth (upper and lower jaws) was assessed before (E_0), immediately after (E_1) and 24 h after treatment (E_2), using a shade guide (VITA classical). Statistical testing was accomplished using the Mann-Whitney U test (p<0.001). The dropout rate was 0%. Results: There were no significant differences at E_0 between placebo and test groups regarding the tooth color. Differences in tooth color changes immediately after (ΔE1_0) and 24 h after treatment (ΔE2_0) were calculated for both groups. The mean values (standard deviations) of tooth color changes for ΔE1_0 were 2.26 (0.92) in the test group and 0.01 (0.21) in the placebo group. The color changes for ΔE2_0 showed mean values of 2.15 (1.10) in the test group and 0.07 (0.35) in the placebo group. For ΔE1_0 and ΔE2_0 significant differences were found between the groups. Conclusion: In this short-term study, the results showed that a non-hydrogen peroxide bleaching agent has significant whitening effects immediately and 24 h after a single-use treatment.

Os pricipais efeitos colaterais do clareamento dentário: como amenizá-los / Tooth whitening: main T collateral effects and how to smooth them

Introdução: em busca de uma perfeita harmonia na forma e nas cores dos dentes, a dentística desenvolveu diversas alternativas para a melhoria da estética dentária, sendo que para o tratamento das alterações cromáticas, o procedimento mais utilizado atualmente é o clareamento dental. Objetivo: realizar uma revisão de literatura a cerca dos possíveis efeitos colaterais advindos das técnicas de clareamento dental e como minimizá-los. Material e Métodos: revisão de literatura por meio de busca bibliográfica nas bases de pesquisa online: PubMED, Medline, Lilacs, Scielo e Scopus, através do rastreio de artigos relevantes publicados entre o período de 2010 a 2016. Resultados: dentre os efeitos colaterais apresentados pelo clareamento dental, a sensibilidade durante e após o clareamento tem sido um dos efeitos adversos mais apontados na literatura, fato que pode ser resultado do aumento da permeabilidade do esmalte, com uma possível difusão do peróxido até a polpa, os tratamentos mais eficazes no controle da sensibilidade são: nitrato de potássio a 5%, fluoreto de sódio neutro a 2%, a terapia a laser e o uso de analgésicos e anti-inflamatórios. O gel clareador deve ser removido totalmente ao final do clareamento, porém se alguma quantidade do mesmo é deixada para trás, o paciente pode eventual deglutir, o que pode levar a irritação na mucosa gastrointestinal, dessa forma é importante que seja evitado o excesso de produto e de aplicações, atentando com a remoção cuidadosa dos excessos, para evitar sua ingestão e contato com tecidos moles. Conclusão: independentemente da técnica de clareamento a ser utilizada é necessária a supervisão e acompanhamento de um cirurgião-dentista, pois com o seu criterioso diagnóstico e adequado tratamento é que os resultados satisfatórios serão alcançados e os efeitos colaterais evitados e/ou minimizados. (AU)

Introduction: in order to achieve a perfect harmony in the shape and colors of the teeth, the dentistry has developed several alternatives for the improvement of dental aesthetics, and for the treatment of chromatic alterations, the most commonly used procedure is tooth whitening. Objective: to carry out a literature review about the possible side effects of dental bleaching techniques and how to minimize them. Material and Methods: a review of the literature was carried out through a bibliographic search in the following online databases: PubMED, Medline, Lilacs, Scielo and Scopus, through the screening of relevant articles published between 2010 and 2016. Results: among the side effects of tooth whitening, sensitivity during and after bleaching has been one of the most commonly reported adverse effects in the literature, a fact that may be a result of increased permeability of the enamel, with a possible diffusion of the peroxide to the pulp. The most effective treatments for sensitivity control are: 5% potassium nitrate, 2% neutral sodium fluoride, laser therapy and the use of analgesics and anti-inflammatories. The bleaching gel should be removed completely at the end of bleaching, but if any amount is left behind, the patient may eventually swallow, which may lead to irritation in the gastrointestinal mucosa, so it is important to avoid excess product And applications, with the careful removal of excess, to avoid its ingestion and contact with soft tissues. Conclusion: regardless of the technique of whitening to be used, it is necessary the supervision and follow-up of a dental surgeon, because with his careful diagnosis and appropriate treatment, satisfactory results will be achieved and the side effects avoided and/or minimized. (AU)

Tooth whitening recovers the color of pre-stained composites

Aim: To assess the effect of home-whitening on aged and stained composite. Methods: Fifteen disc-shaped specimens (10 mm diameter x 2 mm thick) of Filtek Z350XT, shade A2E were fabricated, polished and embedded in wax, leaving exposed the top surface. The specimens were allocated to three groups (n=5): A ­ the specimens remained dry; B ­ conditioning in distilled water and; C ­ conditioning in distilled water and coffee. They were next subjected to whitening with 10% carbamide peroxide (Whiteness Perfect) for 4 h daily for 1, 2 and 4 weeks. Shade was measured with a spectrophotometer Easyshade and expressed based on the CIE L*a*b* system (ΔE*). Surface roughness was measured with a roughness meter (Ra-µm). Data were analyzed with two-way ANOVA and Tukey's test (α=0.05). Results: Conditioning, grouping and the interaction between both, influenced the ΔE* (p<0.0001), which exceeded the 3.3 threshold for visible color change after conditioning of Group C in black coffee. Whitening for 1 week significantly reduced ΔE* in this group. There were no significant changes in surface roughness. Conclusions: Home-whitening did not alter significantly the color of the nanocomposite, except when it was previously stained. One-week whitening was sufficient to recover color change to an acceptable level (Au)

Comparative clinical study of the effectiveness of different dental bleaching methods - two year follow-up

This study evaluated color change, stability, and tooth sensitivity in patients submitted to different bleaching techniques. MATERIAL AND METHODS: In this study, 48 patients were divided into five groups. A half-mouth design was conducted to compare two in-office bleaching techniques (with and without light activation): G1: 35% hydrogen peroxide (HP) (Lase Peroxide - DMC Equipments, São Carlos, SP, Brazil) + hybrid light (HL) (LED/Diode Laser, Whitening Lase II DMC Equipments, São Carlos, SP, Brazil); G2: 35% HP; G3: 38% HP (X-traBoost - Ultradent, South Jordan UT, USA) + HL; G4: 38% HP; and G5: 15% carbamide peroxide (CP) (Opalescence PF - Ultradent, South Jordan UT, USA). For G1 and G3, HP was applied on the enamel surface for 3 consecutive applications activated by HL. Each application included 3x3' HL activations with 1' between each interval; for G2 and G4, HP was applied 3x15' with 15' between intervals; and for G5, 15% CP was applied for 120'/10 days at home. A spectrophotometer was used to measure color change before the treatment and after 24 h, 1 week, 1, 6, 12, 18 and 24 months. A VAS questionnaire was used to evaluate tooth sensitivity before the treatment, immediately following treatment, 24 h after and finally 1 week after. RESULTS: Statistical analysis did not reveal any significant differences between in-office bleaching with or without HL activation related to effectiveness; nevertheless the time required was less with HL. Statistical differences were observed between the results after 24 h, 1 week and 1, 6, 12, 18 and 24 months (intergroup). Immediately, in-office bleaching increased tooth sensitivity. The groups activated with HL required less application time with gel. CONCLUSION: All techniques and bleaching agents used were effective and demonstrated similar behaviors.

In vitro study on tooth enamel lesions related to whitening dentifrice.

Background: The tooth whitening substances for extrinsic use that are available in Brazil contain hydrogen peroxide or carbamide peroxide. Several studies have attributed the appearance of lesions in the enamel morphology, including hypersensitivity, to these substances. Such lesions justify fluoride therapy and application of infrared lasers, among other procedures. However, there is no consensus among researchers regarding the relevance of the severity of lesions detected on the tooth surface. Objectives: The present study was carried out with an aim of evaluating in vitro the effects of the hydrogen peroxide, carbamide peroxide and sodium bicarbonate contained in dentifrice formulations, on human tooth enamel. Materials and Methods: After darkening process in laboratory, human premolars were brushed using dentifrice containing the two whitening substances (Rembrandt - carbamide peroxide and Mentadent - hydrogen peroxide) and the abrasive product (Colgate - sodium bicarbonate). The degree of specimen staining before and after this procedure was determined using spectrophotometry. Scanning electron microscopy (SEM) was used to obtain images, which were analyzed to show the nature of the lesions that appeared on the enamel surface. Results: The effectiveness of the whitening caused by hydrogen peroxide and carbamide peroxide and the abrasion caused by bicarbonate were confirmed, given that the treated test pieces returned to their original coloration. Based on SEM, evaluation of the enamel surfaces subjected to the test products showed that different types of morphologic lesions of varying severity appeared. Conclusions: Whitening dentifrice containing hydrogen peroxide and carbamide peroxide produced lesions on the enamel surface such that the greatest sequelae were associated with exposure to hydrogen peroxide.