A review of the biological and clinical aspects of radiation caries.

AIM: The aim of this article is to review the clinical and biological features underlying the development and progression of radiation caries. BACKGROUND: Although radiotherapy (RT) plays an important role in the management of patients with head and neck cancer (HNC), it is also associated with several undesired side effects such as radiation caries which is a common, yet serious, complication. To review the condition, the Pubmed database was searched using the keywords "radiotherapy," "radiation," "caries," "hyposalivation," "prevention" and "management". Only studies published in the English language were selected. Cross-referencing identified additionally relevant studies. REVIEW RESULTS: RT leads to alterations in the dentition, saliva, oral microflora, and diet of patients. Consequently, irradiated patients are at increased risk for the development of a rapid, rampant carious process known as radiation caries. Motivation of patients, adequate plaque control, stimulation of salivary flow, fluoride use, and nutritional orientation are essential to reduce the incidence of radiation caries and ultimately improve the quality of life for HNC patients. CONCLUSION: Radiation caries is an aggressive side effect of RT. Dentists play an important role in the prevention of the condition via comprehensive oral healthcare before, during, and after the active cancer therapy. CLINICAL SIGNIFICANCE: Dentists should understand the clinical and biological aspects underlying radiation caries to prevent the development of lesions and provide optimal treatment when needed.

Clinical evaluation of in-office dental bleaching treatments with and without the use of light-activation sources.

This study clinically evaluated the alteration of color, color stability, dental sensitivity and gingival irritation on patients undergoing dental bleaching using varying bleaching methods and light-activation sources. According to pre-established criteria, 40 patients were selected and randomly divided into four groups (n=10): Group 1--35% Hydrogen Peroxide (HP); Group 2--35% HP plus Halogen Curing Light XL 3000 (3M/ESPE); Group 3--35% HP plus Demetron LED (Kerr) and Group 4--35% HP plus LED/LASER (Bio-art). For all groups, there were two sessions of bleaching with 35% HP, with a one week break between sessions. At each bleaching session, three applications of the bleaching gel were used. Two methods of shade evaluation were performed before and after the first week, second week, first month and after six months of the bleaching treatment. These methods were VITA Easyshade Spectrophotometer and Vita Classical Shade Guide. Statistical analysis using ANOVA demonstrated equality between the participating groups when evaluating the group and time variables. The In-Office dental bleaching treatments of vital teeth with 35% HP did not prove to be more effective when light sources were used. There was no difference in color stability between groups until the sixth month of evaluation.

Technology-enhanced caries detection and diagnosis.

The prevalence of dental caries in children and adults in the United States has been declining the past 40 years primarily because of increased use of fluoride, improved oral hygiene and better oral hygiene devices, a greater emphasis on disease prevention and control, and better access to dental care made available by the dental profession. Caries diagnosis and detection for pit-and-fissure lesions has changed dramatically in the past 25 years. Research has confirmed that the carious process is bacterially mediated and is accompanied by changes in salivary flow and pH and the intake of refined carbohydrates. In recent years a number of new technologies have become available as adjuncts to traditional methods of diagnosing carious lesions. While using these new technologies, the clinician still needs to understand the concepts of caries risk, diagnosis, detection, and assessment. Working from the evidence, dental practitioners can decide on a sound clinical diagnosis and treatment plan.

Interfacial morphology of self-etching adhesive systems in dentin.

OBJECTIVE: To portray and assess the interfacial morphology achieved with self-etching systems in dentin under observation by scanning electron microscopy. METHOD AND MATERIALS: Ten caries-free extracted erupted human third molars were used in this study. The occlusal enamel was removed, and 10 dentin disks with a thickness of 800 +/- 200 Microm were obtained by slow-speed sectioning with a diamond saw parallel to the occlusal surface. A standard smear layer was created on the occlusal surface by wet sanding with 600-grit sandpaper for 60 seconds. The dentin disks were randomly assigned to one of the systems: AdheSE (Ivoclar Vivadent), Optibond Solo Plus-Self-Etch (Kerr), Tyrian SPE (Bisco) as self-etching primers, and Adper Prompt Self-Etch (3M Espe) and One-Up Bond F (Tokuyama) as self-etching adhesives. All systems were applied according to the manufacturers' instructions. After application of the adhesive systems, a 1.0-mm-thick layer of a flowable composite resin (Filtek Flow; 3M Espe) was applied to the treated dentin surface and light cured for 40 seconds. The specimens were then processed for observation by scanning electron microscopy. RESULTS: All self-etching systems achieved the formation of sealed interfaces and hybridized areas with variable extents except for the self-etching adhesive One-Up Bond F, which showed some gap formation and poor hybridization. Optibond Solo Plus-Self-Etch presented a more consistent adhesive interface with thicker hybrid layers, numerous resin tags, and lateral branches. CONCLUSION: Regarding the micromorphology aspect, Optibond Solo Plus-Self-Etch showed the finest result, while One-Up Bond F was not able to produce a satisfactory ultrastructural morphology.

A simplified approach for layering composite resin restorations.

Although composite restorations can provide excellent results, it is possible that general dentists might find some of the currently proposed techniques to be complicated and demanding. This article reviews some of these concepts and presents a protocol that makes highly esthetic restorations simple yet predictable.

Effect of led light curing on the marginal sealing of composite resin restorations.

Light-emitting diode (LED) curing units are becoming increasingly popular; however, questions remain about their ability to adequately polymerize composite resins. This study was conducted to evaluate the marginal seal of restorations placed with a tungsten halogen curing unit compared to three LED curing units through a microleakage test. The results did not indicate statistical differences between the groups tested for both enamel and dentin margins. Variation of the light-curing unit (quartz tungsten halogen or LED) did not result in discernible differences in the marginal sealing of composite restorations.

Dentin bond strength of self-etching primers/adhesives.

This study compared the shear bond strengths (SBS) to dentin achieved with six self-etching systems and one total-etch one-bottle adhesive system. Seventy freshly extracted bovine incisors were mounted in acrylic molds and the facial surfaces ground to expose middle dentin, which was polished by 600-grit sand paper. The incisors were randomly assigned to groups (n=10): Adper Prompt Self-Etch Adhesive, 3M-ESPE (ADP) and One-Up Bond F, Tokuyama (OU) as self-etching adhesives; AdheSE, Ivoclar-Vivadent (ADH), Clearfil SE Bond, Kuraray (SE), Optibond Solo Plus-Self-Etch, Kerr (OP) as self-etching primers, Tyrian SPE, BISCO (TY) as a self-priming etchant and Single Bond, 3M-ESPE (SB), a total-etch one-bottle adhesive served as a control. All adhesives were applied according to the manufacturers' instructions with the respective hybrid composites. The specimens were thermocycled for 500 cycles (5 degrees C to 55 degrees C), then loaded to failure in an Instron Universal Testing Machine at a crosshead speed of 0.5 mm/minute. Mean bond strengths were analyzed with one-way ANOVA, followed by a Duncan's post hoc test. SBS (mean +/- SD) were: ADH = 13.2 (+/- 5.3)b;ADP = 6.8 (+/- 4.4)c; OP = 18.2 (+/- 3.8)a; OU = 3.5 (+/- 1.5)c; SB = 12.2 (+/- 4.2)b; SE = 12.4 ( +/- 4.0)b; TY = 5.5 (+/- 1.4)c. Superscript letters indicate Duncan's homogeneous subsets. The self-etching adhesives OU and ADP and the self-priming etchant TY resulted in lower dentin SBS. OP resulted in the highest mean dentin SBS, while the other materials tested in this study (SE and ADH) presented similar dentin SBS to a total-etch one-bottle bonding system (SB).

Effect of placement techniques on the marginal adaptation of Class V composite restorations.

STATEMENT OF THE PROBLEM: Several techniques are proposed for the restoration of Class V cavities but there is no agreement in the literature as to which technique is more effective. PURPOSE: To evaluate the effect of different techniques of composite increment placement on the marginal adaptation of Class V restorations. METHODS AND MATERIALS: Twenty-four human molars were selected and prepared with standardized saucer-shaped cavity dimensions of 3.0 mm (occlusal-gingival), 2.0 mm (mesial-distal), and 2.0 mm (depth). The margins are in reference to the cemento-enamel junction with 1.5 mm being located on enamel and 1.5 mm on dentin. The cavities were randomly assigned into three groups (n=8) and restored with composites as follows: Group 1, the occlusal increment was placed and cured first followed by the gingival increment; Group 2, the gingival increment was placed and cured first followed by the occlusal increment; and Group 3, the cavities were restored with one bulk increment. Restorations were immediately finished and stored for 24 h in tap water. Specimens were subjected to thermocycling (1000 cycles, 5 degrees C to 55 degrees C, 30 s dwell time) and immersed in 0.5% basic fuchsin solution for 24 h in room temperature. After rinsing with running water, the restorations were sectioned longitudinally and enamel and dentin margins were evaluated and scored according to the microleakage on a 0-3 scale. Data were subjected to Kruskal-Wallis test at p<0.05. RESULTS: Median of microleakage scores for all evaluated groups was zero. No statistical difference was observed among the three groups both in enamel (p = 0.5929) and dentin (p = 0.3679) margins CONCLUSION: The placement technique did not influence the marginal adaptation of moderate Class V restorations. CLINICAL SIGNIFICANCE: No differences on marginal adaptation were observed when restoring conservative Class V cavities using incremental or bulk placement techniques.

Flowable composites as "filled adhesives:" a microleakage study.

OBJECTIVE: The purpose of this in vitro study was to investigate the microleakage at dentin margins of a flowable resin composite associated with an adhesive, either light cured separately or co-cured, in Class V cavities. MATERIALS AND METHODS: Twenty four recently extracted human molars were prepared with standardized box-shaped Class V cavities of 3.0 mm (mesial-distal), 2.0 mm (occlusal-gingival), and 2.0 mm depth with margins located on enamel and dentin/cementum on the buccal or lingual surfaces. The cavities were randomly assigned into three groups (n=8): Group I - Single Bond + Filtek Z250 (control); Group II - Single Bond + Filtek Flow (light cured separately) + Filtek Z250; and Group III - Single Bond + Filtek Flow co-cured (light cured simultaneously) + Filtek Z250. After being immersed in tap water for 24 h, the specimens were thermocycled (1000x, 5 degrees -55 degrees C, 30 sec dwell time) and immersed in a 0.5% basic fuchsine solution for 24 h. The restorations were sectioned longitudinally and gingival margins were evaluated for microleakage using a 0-4 scale. Data were subjected to the Kruskal-Wallis test at p<0.05. RESULTS: A statistically significant difference at p = 0.0044 between Groups 1 and 3 and Groups 2 and 3 was observed. Although Group 2 performed slightly better than Group 1, no significant difference was observed. CONCLUSION: The use of a flowable resin composite cured simultaneously with an adhesive yielded the worst results in this study. As no statistical differences were seen between Groups 1 and 2, the use of a flowable composite as a means of minimizing microleakage at dentin margins may be questioned.

Silicone index: an alternative approach for tooth fragment reattachment.

UNLABELLED: Tooth fragment reattachment is a simple, conservative, fast, and affordable treatment option for fractured teeth when the fragment is available. However, this technique can present some difficulties, among which is the possibility of the fragment being positioned and bonded inadequately. To avoid this situation, it is necessary to establish a reference for the adequate positioning of the fragment using a silicone index. CLINICAL SIGNIFICANCE: This article presents an alternative approach for better handling of tooth fragments resulting from trauma by using a silicone index as a guide to proper positioning and bonding.

Efeito do clareamento dental sobre a resistência adesiva do esmalte / Effect of bleaching on the shear bond strength of the enamel

Objetivo: Avaliar o efeito do clareamento dental sobre a resistência adesiva ao esmalte. Métodos: Foram selecionados cinqüenta molares, os quais foram divididos aleatoriamente em cinco grupos (n=10); G1-sem clareamento (controle); G2-clareado com peróxido de carbamida a 10% e restaurado 24h após; G3-clareado com peróxido de carbamida a 10%e restaurado sete dias após; G4-clareado com peróxido de hidrogênio a 35% e restaurado 24h após; G5-clareado com peróxido de hidrogênio a 35% e restaurado sete dias após. Durante os intervalos de 24h e sete dias os corpos-de-prova ficaram armazenados em saliva artificial, quando então foram executados os procedimentos restauradores sobre o esmalte.Resultados: O ensaio de resistência adesiva por microcisalhamento indicou os seguintes resultados em MPa (ANOVA e Tukey poste-hoc):G1-43,15 a (±5,19); G2-31,34 ab (± 4,41); G3-36,66 ab (± 3,11); G4-22,87 c (±3,76) e G5-35,67 ab (± 4,64). Conclusão: Os grupos G1, G2, G3 e G5 não tiveram diferença estatística e o grupo G4 (clareado com peróxido de hidrogênio a 35% e restaurado 24 após) teve sua resistência adesiva entre o esmalte clareado e a resina composta diminuída.

Objective: To evaluate the effect of dental bleaching on the shear bond strength of enamel. Methods: Fifty molars were selected and divided into five groups (n=10); G1-without bleaching (control); G2-bleached with 10% carbamide peroxide and restored 24h later; G3-bleached with 10% carbamide peroxide and restored seven days later; G4-bleached with 35%hydrogen peroxide and restored a 35% and restored 24h later; G5-bleached with 35% hydrogen peroxide and restored a 35% and restoredseven days later. During the 24h and 7-day intervals the test specimens remained stored in artificial saliva, after which the restorative procedures were performed on the enamel. Results: The microshear bond strength test indicated the following results in MPa (ANOVA and Tukey post-hoc): G1-43.15 a (±5.19); G2-31.34 ab (± 4.41); G3-36.66 ab (± 3.11); G4-22.87 c (±3.76) and G5-35.67 ab (± 4.64). Conclusion: Groups G1, G2, G3 and G5 showed no statistical difference and Group G4 (bleached with 35% hydrogen peroxide and restored 24h later) showed diminished bond strength between the bleached enamel and resin composite.

Influência do gel de ascorbato de sódio na resistência adesiva entre resina composta e esmalte clareado / Influence of the sodium ascorbate gel on bond strength between resin composite and bleached enamel

O objetivo deste estudo foi avaliar o efeito de diferentes géis de ascorbato de sódio na resistência adesiva entre resina composta e esmalte clareado. Vinte e quatro molares humanos foram selecionados e seccionados no sentido mésio-distal, formando 48 espécimes de esmalte divididos em seis grupos (n = 8): G1- sem clareamento; G2 - somente clareado (P.H. a 7,5%); G3 - clareado + ascorbato (P.H. a 7,5% + 10% de gel ascorbato de sódio); G4 - clareado + ascorbato + flúor (P.H. a 7,5% + 10% de gel ascorbato de sódio com fluoreto de sódio a 2%); G5 - clareado + ascorbato (P.H. a 7,5% + 40% de gel ascorbato de sódio) e G6 - lareado + diário (P.H. a 7,5% + 40% gel de ascorbato de sódio). O clareamento foi executado por 1 hora/dia, durante 14 dias, com peróxido de hidrogênio a 7,5%. Nos Grupos 3, 4 e 5, os géis de ascorbato foram aplicados apenas uma vez após o término da última sessão de clareamento. No Grupo 6, o gel de ascorbato a 40% foi aplicado diariamente. Após 24 horas, foram realizados os procedimentos adesivos com Single Bond + Filtek Z-250 (3M-ESPE). Os espécimes foram cortados e a resistência adesiva testada em máquina de ensaio universal (Instron, Modelo 4444, Canton, Ma, EUA). As médias da resistência adesiva e do desvio padrão (MPa + SD): G1 - 25,78a (±9,19); G2 - 5,31b (±6,41); G3 - 14,02b (±7,11); G4 - 13,97b (±4,76); G5 - 20, 49ab (±4,64) e G6 - 27,11a (±6.67). A utilização do gel de ascorbato de sódio a 40%, tanto em única aplicação (G5) ou quando utilizado diariamente (G6), resultou em valores de adesão similares aos do grupo controle.

The objective of this study was to evaluate the effect of different sodium ascorbate gels on the bond strength between composite resin and bleached enamel. Twenty-four recently extracted human molars were selected and sectioned (mesio-distally) to form 48 enamel specimens, that were randomly divided into six study groups (n = 8): G1 - without bleaching (control group); G2 - bleaching (7.5% hydrogen peroxide); G3 - bleaching + 10% sodium ascorbate gel; G4 - bleaching + 10% sodium ascorbate gel with 2% sodium fluoride; G5 - bleaching + 40% sodium ascorbate gel and G6 - bleaching + 40% sodium ascorbate gel (daily use). Bleaching was performed 1h/day for 14 days with a 7.5% hydrogen peroxide. For groups 3, 4 and 5, the ascorbate gels were used only once, after the end of the bleaching procedure, for 1 hour. For group 6, the ascorbate gel 40% was used daily. After 24 h, adhesive procedures with Single Bond + Z-250 (3M-ESPE). The specimens were sectioned and bond strengths mensured with universal testing machine (Instron, Modelo 4444, Canton, Ma, EUA). Mean ìTBS and standard deviation (SD) in MPa were: G1 - 25.78a (±9.19); G2 - 15.31b (±6.41); G3 - 14.02b (±7.11); G4 - 13.97b (±4.76); G5-20.49ab (±4.64) and G6) 27.11a (±7.83). The use of a 40% sodium ascorbate gel either in a single application (G5) or when used daily (G6) achieved similar bond strengths to that of the non-bleached control group.

Diferenças clínicas e de tratamentos entre a fluorose e a hipoplasia do esmalte / Clinica differences and treatment of enamel hypoplasia and fluorosis

O objetivo deste trabalho é esclarecer, de forma didática, as diferenças clínicas para o diagnóstico, as possíveis causas e formas de tratamento da fluorose e da hipoplasia de esmalte. A forma de tratamento depende do grau de acometimento da lesão, que varia de acordo com a intensidade da alteração, podendo associar técnicas conservadoras ou, até mesmo, técnicas mais invasivas. Este artigo demonstra, através de casos clínicos, as formas de tratamento dessas alterações, obtendo resultados satisfatórios e previsíveis.

Novo conceito na clareação dentária pela técnica no consultório / New concept for the in-office bleaching technique

O objetivo deste trabalho foi avaliar o tempo de decomposição e o pH dos agentes clareadores utilizados na clareação do consultório, em relação ao tempo de aplicação. Foram selecionados 4 agentes clareadores e divididos em 4 grupos (n=5): G1 - Opalescence Xtra Boost (Ultradent); G2 - Whiteness HP Maxx (FGM); G3 - Lase Peroxide Sensy (DMC) e G4 - White Gold Office (Dentsply). A manipulação dos agentes clareadores seguiu as orientações do fabricante. Para avaliação da dosagem de peróxido de hidrigênio em relação ao tempo, foi utilizado o método de titulação do peróxido de hidrogênio com permanganato de potássio preconizado pelo manual de farmacopéia americana (USP) e avaliação do pH do agente clareador através do papel indicador universal de Merck. No teste estatístico de ANOVA, foi observado a hipótese de igualdade entre os grupos, avaliando o fator decomposição em relação ao tempo. No tratamento clareador de dentes vitais através da técnica no consultório com peróxido de hidrogênio, não há necessidade de trocas do agente clareador durante a sessão clínica, quando o agente clareador utilizado mantêm o pH neutro.

Clareação de dentes vitalizados através da técnica de consultório e a necessidade da utilização de fontes de luz / In-office vital tooth bleaching and the need to use auxiliary lights

Hoje em dia, sorrisos com dentes bem alinhados e brancos são tão cultuados pela mídia que estes passaram a ser o desejo de grande parte da população. Um dos tratamentos disponíveis, que tem como finalidade melhorar a aparência dos dentes, é a clareação dentária. Este procedimento pode ser realizado em dentes vitais através de duas técnicas: caseira e no consultório. Recentemente, a utilização de fontes auxiliares de luz foi proposta para aumentar a efetividade da clareação obtida em consultório. Este artigo tem como objetivo demonstrar clinicamente o efeito da utilização de uma fonte auxiliar associada à clareação dentária em dentes vitais, através da técnica no consultório, com um produto à base de peróxido de hidrogênio a 35%.

Clareação dentária associada à microabrasão do esmalte para remoção de manchas brancas / Dental bleaching asociated with microabrasion enamel to remove white spots

Atualmente são verificadas, com grande incidência, alterações na superfície do esmalte dentário. A crescente demanda dos pacientes por tratamentos que melhorem a aparência dos dentes, devido à preocupação estética, tem desafiado os cirurgiões-dentistas a buscarem tratamentos conservadores, que resultem em um sorriso harmonioso. O objetivo deste artigo é demonstrar, através do relato de um caso clínico, a remoção de manchas brancas no esmalte por fluorose nos dentes anteriores superiores, pelas técnicas de clareação dentária e microabrasão do esmalte.

Avaliação clínica do clareamento dental pela técnica no consultório / Clinical evaluate of the dental bleaching technique in the office

Este trabalho teve como objetivo avaliar clinicamente a alteração de cor, a sensibilidade dental e a irritação gengival em pacientes submetidos ao clareamento dental. Selecionados 40 pacientes que foram divididos aleatoriamente em 4 grupos: G1 - Peróxido de Hidrogênio (PH) a 35%; G2 - PH a 35% + Luz Halógena Curing Light XL 3000 (3M/ESPE); G3 - PH a 35% + LED Demetron (Kerr) e G4 - PH a 35% + Led/Laser (DMC). Para todos os grupos foi realizado 2 sessões de clareamento com PH a 35% (intervalo de 1 semana), com 3 aplicações do gel em cada sessão. Para avaliação da cor obtida antes a após a 1ª e 2ª sessões do tratamento clareador, foi utilizado dois métodos de avaliação: I - Espectrofotômetro VITA Easyshade; e II - Escala de cor da Vita Clássica. No teste estatístico de ANOVA foi observada a hipótese de igualdade entre os grupos avaliando o fator Grupo e diferença no fator Tempo. O tratamento clareador de dentes vitais através da técnica no consultório com peróxido de hidrogênio a 35%, não melhorou com o uso de fontes auxiliares. Uma sessão clínica através da técnica no consultório não é suficiente para o clareamento de dentes vitais.

Colagem transcirúrgica de fragmento dental: relato de caso clínico / Trans-surgical tooth fragment reattachment: clinical report

Artigo que demonstra a resolução de uma situação clínica complexa - fratura do incisivo central superior em nível subgengival, com alto grau de envolvimento estético -, em que havia grande expectativa por parte do paciente. Após exame clínico e radiográfico, sugeriu-se utilizar a técnica de colagem transcirúrgica do fragmento dental associada à cimentação de um pino de fibra de vidro.

Preparo de dentes para faceta de porcelana guiado por ensaio diagnóstico / Porcelain veneer preparation driven by a diagnostic mock-up

A restauração dos dentes anteriores com facetas de porcelana caracteriza-se por ser um procedimento primariamente estético e capaz de proporcionar a preservação de estrutura dental sadia, em comparação com as coroas totais de metalocerâmica ou as coroas de cerâmica pura. Entretanto, no intuito de obter espaço adequado para a porcelana, o preparo dos dentes por técnica inadequada provoca remoção desnecessária de estrutura dental, trazendo como conseqüência a indesejável exposição de dentina, especialmente em dentes que já apresentam perda parcial de esmalte. Com o propósito de preservar o esmalte, estrutura capaz de gerar maior resistência adesiva do que a dentina e restaurar o volume original dos dentes, este artigo apresenta uma estratégia para o preparo dental de facetas de porcelana guiado por ensaio diagnóstico prévio.