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.

In vitro bacterial adherence on teeth submitted to whitening with musa paradisiaca / Adherencia bacteriana in vitro en dientes sometidos a blanqueamiento con musa paradisiaca

Objetive: To compare in vitro bacterial adherence on teeth submitted to whitening with 50% ethanolic extract of Musa paradisiaca and 35% hydrogen peroxide. Material and Methods: The study was experimental and used 18 premolars that were grouped into: G1 (control), G2 (50% ethanol extract of Musa paradisiaca) and G3 (35% hydrogen peroxide). The teeth were then exposed to a Streptococcus mutans culture for 24 hours, followed by centrifugation in thioglycolate broth. A culture on trypticase soy agar was done with a 1 in 100 dilution, and after 48 hours colony forming units (CFU) were counted. Statistical analysis was performed using the ANOVA test, complemented by the Bonferroni post-hoc. Results: Bacterial adherence was 77x105 CFU/ml in Group 3 using 35% hydrogen peroxide, 40x105 CFU/ml in Group 2 using 50% ethanol extract of Musa paradisiaca, and 89x104 CFU/ml in Group 1 (control). The difference between the three groups was significant (p=0.000). Conclusion: Both whitening methods cause bacterial adherence to the tooth surface, although to a lower degree with Musa paradisiaca.eses.

Objetivo: Comparar la adherencia bacteriana in vitro en dientes sometidos a blanqueamiento con extracto etanólico de Musa paradisiaca al 50% y con peróxido de hidrógeno al 35%. Material y Métodos: Comparar la adherencia bacteriana in vitro en dientes sometidos a blanqueamiento con extracto etanólico de Musa paradisiaca al 50% y con peróxido de hidrógeno al 35%.Resultados: La adherencia bacteriana fue de 77x105 UFC/ml con el peróxido de hidrógeno al 35%, de 40x105 UFC/ml con el extracto etanólico de Musa paradisiaca al 50% y de 89x104 UFC/ml con el control. La diferencia fue significativa entre los tres grupos (p=0.000). Conclusión: Ambos métodos de blanqueamiento causan adherencia bacteriana en la superficie dental, siendo menor con Musa paradisiaca.

Efectividad de la terapia láser combinada con la técnica convencional en pacientes con discromías dentales / Effectiveness of laser therapy combined with the conventional technique in patients with dental dischromya

Introducción: La discromía dental es una afectación estética, de causa multifactorial, caracterizada por el cambio de coloración de uno o varios dientes. Objetivo: Evaluar la efectividad de la terapia láser como fuente de luz y calor en pacientes con discromías dentales. Método: Se realizó un estudio cuasi experimental, de intervención terapéutica, en 24 pacientes con discromías dentales atendidos en la Clínica Estomatológica Provincial DocenteMártires del Moncada de Santiago de Cuba, desde julio de 2017 hasta julio de 2018. Los integrantes del estudio se asignaron de forma aleatoria a 2 grupos de tratamiento:a los pares (grupo de estudio) se les aplicó láser combinado con la técnica convencional de peróxido de hidrógeno;a los impares (grupo control), tratamiento convencional solamente.Se utilizaron las frecuencias absoluta y relativa como medidas de resumen, así como la prueba de X 2 de homogeneidad para la validación estadística, con un nivel de significación de 0,05. Resultados: Para los pacientes del grupo de estudio, la segunda y tercera sesiones fueron más efectivas. Al culminar el tratamiento, ambos resultaron efectivos, pero los que recibieron láser evolucionaron más rápidamente que los tratados solo con peróxido de hidrógeno. Conclusiones: El uso de la terapia láser y peróxido de hidrógeno fue efectivo en pacientes con discromías dentales y demostró que no provoca efectos adversos en los dientes tratados.

Introduction: The dental dischromya is an esthetic disorder, of multifactorial cause, characterized by the change of coloration of one or several teeth. Objective: To evaluate the effectiveness of laser therapy as a source of light and heat in patients with dental dischromya. Method: A quasi-experiment, of therapeutic intervention study, was carried out in 24 patients with dental dischromya assisted in Mártires del Moncada Teaching Provincial Stomatological Clinic in Santiago de Cuba, from July, 2017 to March, 2018. The members of the study were assigned at random with 2 treatment groups: a study group (pairs) to whom laser combined with the conventional technique of peroxide of hydrogen was applied; to odd number patients (control group), conventional treatment only. The absolute and relative frequencies were used as summary measures, as well as the chi-square test of homogeneity for the statistical validation, with a level of significance of 0.05. Results: For the patients of the study group, the second and third sessions were more effective. When culminating the treatment, both were effective, but those that received laser evolved more quickly than those treated with peroxide of hydrogen. Conclusions: The use of the laser therapy and peroxide of hydrogen was effective in patients with dental dischromya and it was demonstrated that doesn't cause adverse effects in the treated teeth.

Clinical Evaluation of 6-Month Efficacy of 40% in-Office Whitening Treatment

ABSTRACT Objective: To assess the 6-month efficacy of natural tooth color change in in-office bleaching treatment in terms of time by using a spectrophotometer. Material and Methods: A total of 20 participants were chairside treated with 40% hydrogen peroxide (HP), three applications each 20 minutes, in one appointment. Instrumental color measurement was performed on six anterior maxillary teeth before bleaching (baseline-t0), immediately after in-office bleaching and rehydration of the teeth (t1), 3 months (t2), and 6 months after bleaching treatment (t3). The spectrophotometer measured the tooth shades based on the CIE L*a*b* color notation system and Bleach index during the period of observation. CIE L*a*b* (ΔEab) color differences were calculated. Results: The color change at t1 was ΔEab = 3.2, at t2 was ΔEab = 1.8, at t3 was ΔEab = 1.2 and overall color change of in-office method was ΔEab = 3.6 (p<0.05). A significant effect for the mean CIEL*a*b* values was detected as within time b* values decreased significantly (p<0.05). Bleach index values significantly decreased during the time of observation, too (p<0.05). Conclusion: The in-office bleaching treatment using 40% hydrogen peroxide was effective, and the results showed a statistically significant decrease in color change during the period of 6-month observation.

Uso de Peróxido de Hidrógeno como Enjuague Bucal Previo a la Consulta Dental para Disminuir la Carga Viral de COVID-19. Revisión de la Literatura / Use of Hydrogen Peroxide as a Dental Pre-consultation Mouthwash to Decrease the Viral Load of COVID-19. Literature Review

RESUMEN: La utilización de enjuagues antisépticos previo a la atención odontológica favorecería la disminución del virus en la cavidad oral. Se ha planteado el uso de peróxido de hidrógeno preconsulta dental. Se revisaron las bases de datos PubMed, Cochrane y Elsevier publicados desde Enero 2019 a junio 2020. Los estudios que cumplieron los criterios de inclusión fueron revisados por 2 autores individualmente. Se realizó una revisión cualitativa de los datos. No existen ensayos controlados aleatorios o estudios de observación clínica sobre el efecto curativo o preventivo del peróxido de hidrógeno contra el COVID-19, pero si protocolos de ensayos clínicos que están en proceso de reclutamiento. El enjuague bucal con peróxido de hidrógeno podría ser una solución viable pre consulta dental que debe ser estudiada para reducir la carga viral del COVID-19.

ABSTRACT: The use of antiseptic rinses prior to dental care would favor the reduction of the virus in the oral cavity. The use of hydrogen peroxide prior to dental consultation has been proposed. PubMed, Cochrane and Elsevier databases published from January 2019 to June 2020 were reviewed. Studies that met the inclusion criteria were reviewed by 2 authors individually. A qualitative review of the data was performed. There are no randomized controlled trials or clinical observation studies on the curative or preventive effect of hydrogen peroxide against COVID-19, but there are clinical trial protocols that are in the process of recruitment. Hydrogen peroxide mouthwash could be a viable solution prior to dental consultation that should be studied, to reduce COVID-19 viral load.

Estabilidad del color en el blanqueamiento intracoronal / Color stability in intracoronal whitening

RESUMEN Introducción: El blanqueamiento intracoronal es una alternativa mínimamente invasiva que permite devolver el color a dientes no vitales tincionados. La estabilidad del color logrado es fundamental para evaluar la predictibilidad de este tipo de tratamiento. Objetivo: Evaluar la estabilidad del color 3 años después del blanqueamiento intracameral con peróxido de hidrógeno y carbamida a diferentes concentraciones. Métodos: Se utilizaron 44 premolares extraídos por indicación ortodóncica, los cuales fueron tratados endodónticamente y pigmentados artificialmente con cromógenos sanguíneos. Las muestras fueron divididas aleatoriamente en 4 grupos de estudio (n = 11) siendo: grupo A: peróxido de carbamida 37 por ciento, grupo B: peróxido de hidrógeno 35 por ciento, grupo C: peróxido de carbamida 100 por ciento y grupo D: control; para luego realizar 4 aplicaciones de agente blanqueador con un intervalo de 4 días entre cada aplicación. El registro del color se realizó mediante espectrofotometría, lo que permitió obtener los valores CIE L*a*b* para calcular la variación total de color entre los parámetros iniciales y finales del tratamiento, así como el control a los 3 años. Resultados: Los resultados fueron analizados mediante las pruebas de Shapiro-Wilks, ANOVA y Mann-Whitney, sin registrar diferencias significativas en la variación total de color al control de los 3 años (p > 0,05). Conclusión: Los resultados del blanqueamiento intracoronal, independiente del tipo y concentración del agente utilizado en este estudio son estables en el tiempo y cualquier variación regresiva de color debe ser atribuida a factores extrínsecos(AU)

ABSTRACT Introduction: Intracoronal whitening is a minimally invasive procedure to restore natural color to stained non-vital teeth. The color stability achieved is fundamental to evaluate the predictability of this type of treatment. Objective: Evaluate color stability 3 years after intracameral whitening with carbamide and hydrogen peroxide at various concentrations. Methods: A total 44 premolars were used which had been extracted by orthodontic indication. The premolars were treated endodontically and artificially pigmented with blood chromogenes. The samples were randomly divided into 4 study groups (n = 11): Group A: 37 percent carbamide peroxide, Group B: 35 percent hydrogen peroxide, Group C: 100 percent carbamide peroxide and Group D: control. Four applications were then made of the whitening agent with a 4-days' separation between them. Color was recorded by spectrophotometry, obtaining the values CIE L*a*b* to estimate total color variation between the initial and final parameters of the treatment, as well as control at 3 years. Results: The results were analyzed with Shapiro-Wilk, ANOVA and Mann-Whitney tests, not finding any significant differences in total color variation with respect to the 3 years' control (p > 0.05). Conclusion: The results of the intracoronal whitening studied are stable throughout time, regardless of the type and concentration of the agent used, and any regressive color variation should be attributed to extrinsic factors(AU)

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.

Effects of bleaching using 10% carbamide peroxide with calcium or amorphous calcium phosphate on enamel mineral content and hardness / Asociación entre la severidad de Hipomineralización Incisivo-Molar (HIM) y lesiones cavitadas de caries en escolares

ABSTRACT This study evaluated enamel mineral content and surface microhardness before and after bleaching treatment using 10% carbamide peroxide (CP) containing calcium (Ca) or amorphous calcium phosphate (ACP). Thirty-six bovine slabs were randomly allocated into 3 groups (n = 12) according to bleaching treatment: G1 - Opalescence PF 10% (CP), G2 -NiteWhite ACP (CP+ACP), and G3 - Opalescence PF (10%) with calcium (CP+CA). The bleaching agent was applied on enamel surface for 6 h/day over a period of 21 days. Enamel surface was evaluated by Knoop microhardness (KNH) and micro energy-dispersive X-ray fluorescence spectrometry (p-EDXRF) at baseline and at after bleaching treatment. Data were statistically analyzed by repeated measures ANOVA and Tukey's test (a = 0.05). There was a significant decrease in microhardness after bleaching treatments for all study groups, but no difference between bleaching gels. There was no difference in the Ca/P ratio measured by p-EDXRF for all groups at the study times, but the mean value was lower in group CP+CA than in group CP+ACP. Group CP was similar to both CP+ACP and CP+CA. It can be concluded that enamel microhardness decreased after the bleaching process, regardless of the presence of calcium or ACP, but there was no significant change in the Ca/P ratio of enamel after bleaching for each tested gel. This indicates that the bleaching gels have erosive potential, causing softening of enamel without promoting surface loss, regardless of the presence of calcium of ACP ions.

RESUMO Este estudo avaliou o conteúdo mineral do esmalte e a microdureza superficial antes e após o tratamento clareador, utilizando peróxido de carbamida 10% (PC) contendo cálcio (Ca) ou fosfato de cálcio amorfo (ACP) em sua composigao. Trinta e seis espécimes de esmalte bovino foram alocados aleatoriamente em 3 grupos (n = 12) de acordo com os tratamentos clareadores: G1 - Opalescence PF 10% (CP), G2 -NiteWhite (CP+ACP); e G3 - Opalescence PF (10%) com cálcio (CP + CA). O agente clareador foi aplicado na superficie do esmalte por 6 h/dia por um periodo de 21 dias. A superficie do esmalte foi avaliada por microdureza Knoop (KNH) e espectrometria de fluorescencia de raios X micro-dispersiva (p-EDXRF) no inicio e após o tratamento clareador. Os dados foram analisados estatisticamente pelo teste ANOVA de medidas repetidas e Tukey (a = 0,05). Houve uma diminuigao significativa da microdureza após os tratamentos clareadores para todos os grupos estudados, mas nao houve diferenga entre os diferentes géis. Nao houve diferenga da relagao Ca/P mensurada por p-EDXRF para todos os grupos nos tempos estudados; no entanto, o grupo CP+CA apresentou menor valor comparado ao grupo CP+ACP. O grupo CP foi similar aos grupos CP+ACP e CP+CA. Portanto, pode-se concluir que houve redugao significativa da microdureza do esmalte após o clareamento, independente da presenga de cálcio ou APC na composigao dos géis, embora nao tenha havido alteragao significando na relagao Ca/P do esmalte após o clareamento. Isto indica um potencial erosivo dos géis clareadores, causando o amolecimento sem perda da estrutura do esmalte, independente da presenga dos íons cálcio e ACP.

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.

Effects of hydrogen peroxide mouthwash on preventing ventilator-associated pneumonia in patients admitted to the intensive care unit

Abstract Aims The aim of the study was to determine the effect of hydrogen peroxide (HP) mouthwash on the incidence of ventilator associated pneumonia (VAP) in patients admitted to the intensive care unit (ICU). Methods This was a randomized clinical trial conducted on 68 patients. The intervention group used 3% HP as mouthwash and the control group used mouthwashes with 0.9% normal saline (NS) twice a day. Data were collected using a questionnaire and the Modified Clinical Pulmonary Infection Score (MCPIS). MCPIS includes five items, body temperature: white blood cell count, pulmonary secretions, the ratio of pressure of arterial oxygen (PaO2) to fraction of inspired oxygen (FiO2), and the chest X-ray. Each of these items scored 0–2. Scores ≥6 were considered as VAP signs. The SPSS-20 software was employed to analyze the data. Results In total, 14.7% patients of the HP group and 38.2% patients of the NS group contracted VAP. The risk of VAP in the NS group was 2.60 times greater than that in the HP group (RR = 2.60, 95% CI: 1.04–6.49, p = 0.0279). The mean ± SD MCPIS was calculated as 3.91 ± 1.35 in the HP group and 4.65 ± 1.55 in the NS group, a difference statistically significant (p = 0.042). There were no significant differences in the risk factors for VAP between the two groups. Conclusion HP mouthwash was found more effective than NS in reducing VAP. HP mouthwash can therefore be used in routine nursing care for reducing VAP.

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)

Clinical diagnosis and treatment of necrotizing ulcerative gingivitis in the orthodontic patient: a case report / Diagnóstico clínico y tratamiento de la gingivitis ulcerativa necrotizante en el paciente ortodóntico: reporte de un caso

Abstract: Introduction: about 0.1 percent of the population suffers from necrotizing ulcerative gingivitis, a disease of rapid progression and acute manifestation, which may progress to necrotizing ulcerative periodontitis and eventually to bone sequestration and loss of gingival tissue. Case report: A 21-year-old female patient undergoing orthodontic treatment for six months, diagnosed with necrotizing ulcerative gingivitis due to acute pain in the gingival tissue, spontaneous bleeding, halitosis and abundant plaque. The treatment was conservative and effective, obtaining total remission of the lesion after seven days and three months of postoperative follow-up. Conclusion: Today there are no epidemiological or clinical reports that support the relationship of necrotizing ulcerative gingivitis and orthodontic treatment. Prevention is critical to the success of the treatment, which is why the dentist should recognize the clinical features of necrotizing ulcerative gingivitis to raise awareness of its risks in the orthodontic patient.

Resumen: Introducción: alrededor del 0.1 por ciento de la población padece de gingivitis ulcerativa necrotizante, una enfermedad de progresión rápida y de presentación aguda que puede progresar a periodontitis ulcerativa necrotizante llegando a desarrollarse secuestros óseos y la pérdida de tejido gingival. Reporte del caso: Paciente femenino de 21 años de edad bajo seis meses de tratamiento ortodóntico, quien fue diagnosticada con gingivitis ulcerativa necrosante, debido a dolor agudo en el tejido gingival, sangrado espontáneo, halitosis y abundante placa bacteriana. El tratamiento fue llevado a cabo de manera conservadora y efectiva, obteniendo la remisión total de la lesión al término de siete días y los tres meses de seguimiento postoperatorio. Conclusión: Hoy en día no existen reportes epidemiológicos ni clínicos que sustenten la relación de la gingivitis ulcerativa necrotizante y el tratamiento ortodóntico. La prevención es decisiva para el éxito del tratamiento, es por ello que el odontólogo debe conocer las características clínicas de la gingivitis ulcerativa necrotizante para hacer conciencia en el paciente ortodóntico.

Dental bleaching with ozone: effects on color and enamel microhardness / Clareamento dental com ozônio: efeitos na cor e na microdureza do esmalte

The aim of this in vitro study was to evaluate the effects of dentalbleaching with ozone (O3) on color change and enamelmicrohardness. Enamel blocks (3 x 3 x 3mm) were randomlydistributed for treatments (n=10). Color change (ΔE) and Knoopmicrohardness of the enamel blocks were evaluated before andafter the following treatments: C – deionized water (control); HP– 37.5% hydrogen peroxide (Pola Office+/ SDI); PLA – placebogel; O3– ozone; and O2– oxygen. Four 8-minute applicationswere used for HP and PLA, and one 19-minute application for O3and O2.One-way ANOVA revealed that ΔE was not significantlyinfluenced by the treatment (p = 0.112). For the treatments withHP, PLA, O3 and O2, ΔE was greater than 3.3. The paired t testshowed significant decrease in microhardness after treatments (p< 0.001) but no significant difference between treatments(ANOVA; p = 0.313). Dental bleaching treatments with O3, HP,O2and PLA induced enamel color changes that may be clinicallydiscernible, although enamel microhardeness decreased.

O objetivo deste estudo in vitro foi avaliar os efeitos doclareamento dental com ozônio (O3) quanto à alteração de core microdureza do esmalte. Blocos de esmalte (3 x 3 x 3mm)foram aleatoriamente distribuídos entre os tratamentos(n=10). Alteração de cor (ΔE) e microdureza Knoop foramavaliados antes e após cada um dos seguintes tratamentos: C– água deionizada (controle); PH – peróxido de hidrogênio a37,5% (Pola Office+/ SDI); PLA – gel placebo; O3– ozônio;O2– oxigênio. Quatro aplicações de PH e PLA foramrealizadas por 8 minutos cada e uma aplicação de O3e O2foram realizados por 19 minutos em cada bloco de esmalte.ANOVA a um critério mostrou que os valores de ΔE não foramsignificativamente influenciados pelo tratamento (p = 0,112).Para os tratamentos com PH, PLA, O3 e O2, o ΔE foi maior que3,3. O teste t pareado mostrou diminução significativa dosvalores de microdureza no final do tratamento quandocomparado com o tempo baseline (p < 0,001), mas não houvediferença significativa entre os tratamentos (ANOVA; p =0,313). O tratamento com O3, PH, O2e PLA levou a alteraçãode cor do esmalte clinicamente perceptível, embora tenha sidoobservada diminuição da microdureza do esmalte com arealização dos tratamentos.

Effect of bleaching agents containing fluoride or calcium on enamel microhardness, roughness and permeability

To evaluate the effect of different in-office bleaching agents on the permeability, roughness and surface microhardness of human enamel. Methods: For evaluation of roughness and microhardness, 40 hemi-faces of 20 premolars were subjected to initial roughness (Ra parameter) and microhardness (VHN) measurements. Thirty-two premolar's crowns were used for permeability test. Then, all specimens were randomly divided into four groups: C - without bleaching (control), HP35 - bleaching with 35% hydrogen peroxide (HP), HPF38 - 38% HP+fluoride, HPC35 - 35% HP+calcium. Final roughness (FR) and microhardness (FM) measurements were evaluated. For permeability, the 32 crowns were immersed in 1% sodium hypochlorite (20 min) and silver nitrate solutions (2 h) and subjected to developing solution under fluorescent light (16 h). Three sections from the crowns were analyzed in light microscope (100x) to evaluate the scores of permeability: Score 0 - no tracer agent penetration; Score 1 - less than half the thickness of enamel penetration; Score 2 - tracer agent reaching half the enamel thickness; Score 3 - entire enamel depth penetration, without reaching dentin and Score 4 - tracer agent reaching dentin. For roughness and microhardness evaluation were used one-way ANOVA and Dunnet post-test for independent samples, and t test for paired samples. For permeability, the data were analyzed by Kruskal Wallis and Dunn tests. Results: A significantly higher permeability and surface roughness were observed in groups HP35, HPF38 and HPC35 compared to the C group, as well as decreased microhardness (p<0.05). Conclusions: All bleaching agents increased permeability and surface roughness, and decreased microhardness of human enamel; thus, the addition of fluoride or calcium was not beneficial...

Combinação de técnicas para clareamento dentário em dentes vitalizados / Combined technique for tooth bleaching of vital tooth

O objetivo deste artigo é descrever o clareamento de dentes vitais utilizando uma combinação de técnica caseira e de consultório. Foi utilizado peróxido de hidrogênio a 35% para a técnica de consultório em combinação com a técnica caseira utilizando peróxido de hidrogênio a 16%. A paciente foi monitorada quanto à mudança de cor dos dentes, de acordo com a escala Vitapan 3D-Master. Concluiu-se que, desde que bem planejado e com correto diagnóstico, a combinação de técnicas clareadoras é uma excelente opção de tratamento estético e conservador para clareamento de dentes com alteração de cor.

The aim of this paper was to describe a vital tooth bleaching employing a combination of in-office and at-home techniques. We used a 35% hydrogen peroxide for the in-office technique combined to home bleaching using hydrogen peroxide at 16%. The patient was monitored for teeth color change, according to the Vitapan 3D-Master scale. It was concluded that, with proper planning and diagnosis, the combination of bleaching techniques is an excellent option for aesthetic and conservative treatment of teeth chromatically altered.

Dental bleaching agents with calcium and their effects on enamel microhardness and morphology

Aim: To evaluate enamel microhardness and morphology after bleaching with hydrogen peroxide containing calcium in different concentrations. Methods: One hundred specimens of human teeth were ground and polished and had the initial microhardness evaluated. The specimens were randomly assigned into five groups (n=20): Group 1 - Control group (no treatment); Group 2 - Home Peroxide 6% (without calcium); Group 3 - Home Peroxide 7.5% (without calcium); Group 4 - White Class 6% (with calcium); Group 5 - White Class 7.5% (with calcium). For each group, the bleaching was performed according to the manufacturer's specifications. The specimens were bleached once a day for 5 days and subjected to pH cycling. Microhardness and scanning electron microscopy (SEM) analysis were performed before and after bleaching. Results: The results showed that groups submitted to bleaching treatment presented hardness loss compared to the control group. The group of 7.5% hydrogen peroxide with calcium showed a lower percentage of hardness loss in relation to other groups. Conclusion: Calcium in association with a higher hydrogen peroxide concentration may decrease microhardness changes on enamel.

Efeito dos tratamentos de superfície no manchamento e na rugosidade do esmalte após clareamento dentário / Effect of surface treatments on enamel staining and roughness after dental bleaching

O esmalte dentário submetido ao clareamento com peróxidos pode tornar-se mais rugoso e mais susceptível ao manchamento que o esmalte não clareado, especialmente logo após o tratamento clareador. O objetivo deste estudo foi avaliar o efeito de diferentes tratamentos de superfície e do tempo de espera para o contato com pigmentos, na rugosidade e na manutenção da cor do esmalte, após clareamento dentário. Cem espécimes de dentes bovinos foram clareados com peróxido de hidrogênio 35% (Whiteness HP, FGM) e tratados de acordo com a divisão em 5 grupos: G1 saliva artificial (controle), G2 fluoreto de sódio neutro 2% (Flugel, DFL), G3 pasta de fosfopeptídeos da caseína-flúor fosfato de cálcio amorfo (CPP-ACPF, MI Paste Plus, GC), G4 líquido para manutenção dos resultados do clareamento dentário (Keep White Rinse, DMC), G5 polimento coronário com discos de feltro impregnados com óxido de alumínio (Super Buff Disk, Shofu)...

Effect of finishing and polishing on surface roughness of composite resins after bleaching

AIM : To evaluate the influence of finishing and polishing techniques on the surface roughness of two composite resins (CRs) subjected to bleaching procedure. METHODS : Forty-eight CR specimens were divided into six groups (n=8). For G1 to G3, a microhybrid CR (Opallis; FGM) was used, and G4 to G6, received a nanohybrid CR (Brilliant NewLine; Coltène/Whaledent). All specimens were subjected to bleaching procedure with 35% hydrogen peroxide (two 45-min applications, with a 5-day interval). The surface roughness of all specimens was evaluated before and after the bleaching and/or finishing/polishing (Ra parameter) by a roughness meter. After bleaching, the groups were subjected to finishing and polishing procedures: G2 and G5 - felt discs + diamond pastes; and G3 and G6 - silicon rubber tips. The control groups (G1 and G4) had no finishing or polishing treatment after bleaching. Data were analyzed by ANOVA and Tukey's post-test, and t test for paired samples (a=0.05). RESULTS : bleaching treatment increased Ra values for the nanohybrid CR specimens, but both finishing/polishing techniques were able to reduce these values; for the microhybrid specimens, only finishing/polishing with silicon rubber tips decreased the roughness values. CONCLUSIONS : For both microhybrid and nanohybrid CRs, the silicon rubber tips were effective to reduce the surface roughness after bleaching procedure...

Effects of various hydrogen peroxide bleaching concentrations and number of applications on enamel

AIM: To evaluate the effects of three hydrogen peroxide (HP) concentrations on enamel mineral content (MC), following three peroxide applications and using three methods to measure the MC. METHODS : Forty samples were obtained from bovine incisors and randomly divided into 4 groups (n=10). The control group remained untreated, while the experimental groups were tested for three HP concentrations (10%, 35% and 50%). The HP gel was applied 3 times on the enamel surface for 30 min per application and the samples were analyzed after each application. The MC of the enamel was determined before and after bleaching using Fourier transform (FT-Raman) spectroscopy and micro energy-dispersive x-ray fluorescence spectrometry (µEDXRF). The calcium (Ca) lost from the bleached enamel was quantified with an atomic absorption spectrometer (AAS). The data were analyzed statistically by ANOVA, Tukey and Dunnett´s tests (p<0.05). RESULTS: The FT-Raman showed a decrease in MC for all bleaching treatments, without influence of the different HP concentrations or the number of applications. µEDXRF did not detect any changes in MC. CONCLUSIONS: Ca loss was observed by the AAS, with no difference among the three HP concentrations. The FT-Raman and AAS analyses detected MC reduction and Ca loss after HP bleaching.