Enamel properties after tooth bleaching with hydrogen/carbamide peroxides in association with a CPP-ACP paste.

BACKGROUND: This study evaluated the impact of bleaching teeth using blends of a CPP-ACP paste (MI Paste; MI) and carbamide/hydrogen peroxides in different proportions on surface properties of bleached enamel. METHODS: Ninety bovine incisors were bleached with 7.5% hydrogen peroxide (HP), 16% carbamide peroxide (CP), MI and blends of HP or CP:MI at three proportions (1:1, 2:1, 1:2). Hardness and roughness were measured at baseline and after bleaching. Enamel morphology was evaluated by Scanning Electron Microscopy (SEM). The data were analyzed by two-way ANOVA for repeated measurements and Tukey's test. RESULTS: Most of the samples bleached with MI in combination with peroxides presented increased hardness and roughness which were associated to mineral deposition, as observed by SEM images. Blends with higher fractions of MI did not offer superior benefits. CONCLUSIONS: The use of a CPP-ACP paste mixed to carbamide/hydrogen peroxides can decrease adverse side-effects from tooth bleaching on an enamel surface.

Influence of air abrasion and long-term storage on the bond strength of self-etching adhesives to dentin.

This study tested the effects of long-term storage and aluminum oxide air abrasion on the bond strength of self-etching adhesive systems. Extracted human third molars were ground flat with 600-grit SiC paper to expose middle coronal dentin. Clearfil SE Bond and One-Up Bond F were applied to dentin surfaces in accordance with manufacturers instructions with or without previous aluminum oxide 50 microm air abrasion. A crown was built up with the resin composite TPH Spectrum and the specimens were stored in water for 24 hours. The bonded assemblies were vertically sectioned into beams for microtensile bond testing. The beams of each tooth were individually immersed in bottles containing water at 37 degrees C for one day, three and six months; the water was changed daily. The specimens were then subjected to microtensile bond testing. The bond strength data were subjected to ANOVA and Tukey Kramer test. Fractured specimens were analyzed in a scanning electron microscope to determine failure modes. Air abrasion improved Clearfil SE Bond bond strength in the three month evaluation. No significant difference was found between the two adhesives systems, but bond strengths gradually decreased over time. Failure modes varied significantly among groups and were influenced by long-term storage and aluminum oxide air abrasion.

Step-cure polymerization: effect of initial light intensity on resin/dentin bond strength in class I cavities.

This in vitro study assessed the effect of a step-cure light curing method on resin/dentin bond strength on the buccal wall of Class I cavities in human teeth. Occlusal enamel was removed to expose a flat dentin surface. Twenty four box-shaped cavities (C-factor = 4.5) were prepared in dentin. Prime&Bond 2.1 was applied and TPH Spectrum (Dentsply) was inserted using a bulk-filling increment. The composite was light-cured using either a step-cure photoactivation technique or a one-step continuous curing method. For step-cure polymerization, the initial cure intensity was varied by changing the distance between the light source and the resin surface. The light-cured resins were cured using four low light intensities: 150(G1), 200(G2), 250(G3) and 300(G4) mW/cm2. In the continuous exposure curing method, the samples were light-activated for 40 seconds at 740 mW/cm2 and irradiation was applied in a box-shaped cavity and a flat cavity (exposed buccal wall, C-factor = 0.22). Samples were prepared for TBS testing by creating bonded beams (of approximately 0.8 mm2) obtained from the buccal wall. The data were analyzed using one-way ANOVA, Tukey Test and Dunnett's Test at a significance level of 0.05. The mean TBS values for the continuous exposure group in the flat and box-shaped cavities were 24.31 and 10.23 MPa, respectively. The corresponding TBS for step-cure polymerization was 23.13 (G3), 18.83 (G2), 14.87 (G1) and 13.26 MPa (G4). Bond strength values to the cavity wall were lower in the three-dimensional cavities and dependent on the light curing method (p < 0.05). The use of a low initial light intensity (200-250 mW/cm2) for 10 seconds followed by high irradiation intensity provided the best bond strengths, similar to bonding in a flat cavity.

Esthetic rehabilitation with indirect resin on anterior teeth: a clinical report / Reabilitação estética com resina indireta em dentes anteriores: um relato clínico / Rehabilitaciónestética con resina indirecta en dientes anteriores: reporte clínico

Introduction:The aesthetic rehabilitation of endodontically treated teeth depends on the destruction degree of the crown, the bone support, type of prosthesis, andchewing forces. In these cases, indirect restorations with composite resins are an excellent alternative. The indirect composite resins have improved physical and mechanical properties due toincorporatingof inorganic fillersand multifunctional monomers. These components offer a greater bonding strength to the indirect restorations, which is advantageous for further rehabilitations with ceramic crowns. Objective:To present an aesthetic rehabilitation of anterior teeth with indirect composite resin as a feasible and less expensive treatment alternative.Case Report:Upon clinical examination, extensive and deficient restorations were observed in the upper anterior teeth. The proposed treatment plan was the aesthetic rehabilitation of endodontically treated teeth with indirect restorations using ceromer.Conclusions:This treatment represented an excellent alternative for aesthetic rehabilitation of endodontically treated teeth in cases of great dental crown destruction or small dental absences (AU).

Introdução:A reabilitação estética de dentes tratados endodonticamente depende do grau de destruição da coroa, do dente em questão, do suporte ósseo, do tipo de prótese e dos tipos de forças a que esses dentes serão submetidos. As resinas compostas indiretas apresentam propriedades físicas e mecânicas aprimoradas graças à incorporação de componentes inorgânicos e monômeros multifuncionais com maior número de pontos de união, tornando-os capazes de solucionar os problemas em que seriam indicadas restaurações cerâmicas. Objetivo:Apresentar um relato de caso clínico de uma reabilitação estética de dentes anteriores com resina composta indireta como alternativa de tratamento viável e de menor custo.Relato de Caso:Ao exame clínico foram observadas restaurações amplas e deficientes nos dentes anteriores superiores. O plano de tratamento proposto reabilitação estética dos elementos dentários com cerômeros.Conclusões:Este tratamento representou uma opção viável e demenor custo que pode ser utilizado tanto em situações de grande destruição dentária como em pequenas ausências dentárias, em substituição às restaurações de cerâmica (AU).

Introducción: La rehabilitación estética de los dientes tratados endodónticamente depende del grado de destrucción de la corona, el diente en cuestión, el soporte óseo, el tipo de prótesis y los tipos de fuerzas a las que estos dientes serán sometidos. Las resinas compuestas indirectas tienen propiedades físicas y mecánicas mejoradas gracias a la incorporación de componentes inorgánicos y monómeros multifuncionales con mayor número de puntos de unión, lo que las hace capaces de resolver los problemas en los que estarían indicadas las restauraciones cerámicas. Objetivo: Presentar un caso clínico de rehabilitación estética de dientes anteriores con resina compuesta indirecta como alternativa de tratamiento viable y menos costosa. Reporte de Caso:En el examen clínico, se observaron restauraciones extensas y deficientes en los dientes anteriores superiores. El plan de tratamiento propuesto para la rehabilitación estética de elementos dentales con cerómeros. Conclusiones:Este tratamiento representó una opción viable y menos costosa que se puede utilizar tanto en situaciones de gran destrucción dentaria como en pequeñas ausencias dentales, en sustitución de las restauraciones cerámicas (AU).

Técnica minimamente invasiva em lesão branca hipoplásica: relato de caso / Minimally invasive technique in hypoplastic white injury: case report / Técnica minimamente invasiva en lesiónblancahipoplástica: caso clínico

Introdução:As manchas dentárias, dentre elas a hipoplasia do esmalte,corresponde a um dos motivos que fazem com que os pacientes busquem alterações no seu sorriso.O tratamento proposto deve ser sempre o mais conservador possível e buscar devolver a autoestima do paciente. Objetivo:Este trabalho objetivou apresentarum relato de caso clínico de paciente do sexo feminino, 26 anos, insatisfeita com a estética do seu sorriso por apresentar dentes escurecidos e hipoplasia de esmalte na face vestibular, em incisivo superior.Descrição do caso:Ao exame clínico foi observado escurecimento fisiológico e hipoplasia de esmalte no incisivo lateral superior esquerdo (22).O plano de tratamento proposto foi clareamento dental pela técnica associada (técnica de consultório + técnica caseira), remoção da mancha hipoplásica de formaminimamente invasiva e restauração em resina composta direta. Conclusões:Através de um correto diagnóstico, associado a uma técnica e seleção de material adequado, foi possível conseguir excelência estética com preservação de estrutura dentária sadia (AU).

Introduction:Dental stains, including enamel hypoplasia, correspond to one of the reasons that make patients seek changes in their smile. The proposed treatment should always be as conservative as possible and seek to restore the patient's self-esteem.Objective:This study aimedto present a clinical case report of a 26-year-old female patient, dissatisfied with the aesthetics of her smile as she had darkened teeth and enamel hypoplasia on the vestibular face, in anupper incisor. Case description:On clinical examination, physiological darkening and enamel hypoplasia were observedon the left upper lateral incisor (22). The proposed treatment plan was dental bleaching using the associated technique (In-office bleaching+ at-home bleaching), removal of the hypoplastic stain in a minimally invasive manner and restoration in direct composite resin.Conclusions:Through a correct diagnosis, associated with a technique and selection of suitable material, waspossible to achieve aesthetic excellence with preservation of healthy dental structure (AU).

ntroducción: Las manchas dentales, incluida la hipoplasia del esmalte, corresponden a una de lasrazones que hacenquelos pacientes busquencambios em susonrisa. El tratamiento propuestosiempredebe ser lo másconservador posible y tratar de restablecerla autoestima del paciente.Objetivo: Este estudio tuvo como objetivo presentarun informe de caso clínico de una paciente de 26 años de edad, insatisfechacon la estética de susonrisa, ya que habíaoscurecidolosdientes y la hipoplasia del esmalte en lasuperficie vestibular, en el incisivo superior.Descripcióndel caso: Enelexamen clínico, se observó oscurecimiento fisiológico e hipoplasia del esmalte en el incisivo lateral superior izquierdo (22). El plan de tratamiento propuestofueel blanqueamiento dental utilizando la técnica asociada (técnica de consultorio + técnica casera), eliminación de la mancha hipoplásica de maneramínimamente invasiva y restauraciónen resina compuestadirecta. Conclusiones: A través de un diagnóstico correcto, asociado con una técnica y selección de material adecuado, fueposible lograr laexcelencia estética conlapreservación de una estructura dental sana (AU).

Effect of polymerization modes and resin composite on the temperature rise of human dentin of different thicknesses: an in vitro study.

This in vitro study evaluated the effect of different polymerization modes and the presence of resin composite on the temperature rise (TR) in human dentin of different thicknesses. For this purpose, 90 specimens were assigned to 30 groups (n=3): five polymerization modes (1-conventional; 2-soft-start; 3-high intensity; 4-ramp cure: progressive and high intensity; 5-high intensity with the tip of the light cure at a distance of 1.3 cm for 10 seconds and the tip leaned in the sample); two levels of resin composite presence (absence or presence of resin composite) and three dentin thicknesses (1, 2, 3 mm). During polymerization, temperature was measured by a digital laser thermometer (CMSS2000-SL/SKF). Three-way ANOVA and Tukey tests were performed. There were statistical differences in TR among polymerization modes, presence of resin composite and dentin thicknesses. Within the limits of this study, it can be concluded that 1) conventional and high intensity polymerization modes presented lower TR means, and it was statistically different from soft start, distanced tip and ramp curing polymerization modes; 2) the presence of resin composite showed a statistically significant reduction TR means and 3) the thicker the dentin, the less the temperature rise.

Harmonização do sorriso com laminados cerâmicos: relato de caso / Harmonization of smile with ceramic veneers: case report / Armonización de la sonrisa con laminados cerámicos: informe de caso

Introdução: Os padrões de beleza atuais aumentaram o nível de exigência estética e a busca por sorrisos cada vez mais harmônicos. As facetas cerâmicas destacam-se dentre as opções de tratamentos por associarem estética, longevidade e previsibilidade. Objetivo: Este trabalho objetivou apresentar um caso clínico de substituição de facetas diretas de resina composta por facetas indiretas de porcelana. Descrição do caso: A pacienteC.L.M, 25 anos, sexo feminino relatou insatisfação com a estética do seu sorriso, destacando o formato, o tamanho e a cor 1M2dos elementos dentários 11 e 21. Diante da queixa e da situação clínica observada, propôs-se a confecção de laminados cerâmicos de dissilicato de lítio, mediante a realização prévia de gengivoplastia e de clareamento dentário. Conclusões: Conclui-se que o planejamento cuidadoso, o conhecimento da técnica operatória e a execução adequada do protocolo reabilitador permitem que os laminados cerâmicos reestabeleçam o sorriso de forma estética e funcional (AU).

Introduction:The current beauty standards have increased the level of aesthetic demand and the search for more and more harmonious smiles. The ceramicveneers stand out among the treatment options for combining aesthetics, longevity and predictability. Objective:This study aimed to present a clinical case of substitution of direct resin veneers composed of indirect porcelain veneers. Case description:Patient C.L.M, 25 years old, female, reported dissatisfaction with the aesthetics of her smile, highlighting the shape, size and 1M2 colorof dental elements 11 and 21. In view of the complaint and the clinical situation observed, it was proposed to make lithium disilicate ceramic veneers, through previous gingivoplasty and tooth bleaching. Conclusions:It is concluded that the careful planning, the knowledge of the operative technique and the proper execution of the rehabilitation protocol allow the ceramic veneers to reestablish the smile in an aesthetic and functional way (AU).

Introducción: los estándares de belleza actuales han aumentado el nivel de demanda estética y la búsqueda de sonrisas cada vez más armoniosas. Las facetas cerámicas se destacan entre las opciones de tratamiento para combinar estética, longevidad y previsibilidad. Objetivo: Este estudio tuvo como objetivo presentar un caso clínico de sustitución de carillas de resina directas compuestas de carillas de porcelana indirectas.Descripción del caso: La paciente C.L.M, 25 años, mujer, refirió insatisfacción con la estética de su sonrisa, destacando la forma, tamaño y color 1M2de los elementosdentales 11 y 21. En vista de la queja y la situación clínica observada, se propuso hacer laminados de cerámica disilicato de litio, mediante reparación gingival previa y blanqueamiento dental. Conclusiones: se concluye que la planificación cuidadosa, el conocimiento de la técnica operativa y la ejecución adecuada del protocolo de rehabilitación permiten a los laminados cerámicos restablecer la sonrisa de una manera estética y funcional (AU).

A quantitative method of measuring the microleakage of thermocycled or non-thermocycled posterior tooth restorations.

This study quantified microleakage in restorations made with three packable resin composites-Solitaire, SureFil and P60; one hybrid resin composite-Z250 and an amalgam-Dispersalloy, with or without the thermocycling process. Sixty sound, freshly extracted human molars were sectioned mesiodistally, creating buccal and lingual blocks. One hundred blocks with the flattest surface were selected. Cylindrical cavities with a diameter of 1.85 +/- 0.05 mm and a depth of 1.5 mm were prepared with a special diamond bur. The blocks were randomly assigned to 10 test groups (n = 10): five restorative materials and two thermal stress groups (thermocycled groups at 3,000 cycles at 5 degrees C and 55 degrees C with a dwell time of one minute at each temperature, or non-thermocycled). After the thermocycling test, the samples were immersed in 2% methylene blue for 12 hours. The samples were ground and the powder prepared for analysis in an absorbance spectrophotometer. All the results were statistically analyzed by the Kruskal-Wallis test and the Mann Whitney test. For the non-thermocycled groups, the means (microg/ml) of microleakage were: Amalgam-4.279 (a); Solitaire-4.148 (ab); Z250-3.418 (abc); P60-3.184 (bc); SureFil-2.890 (c). For the thermocycled groups, the means were: Amalgam-7.572 (a); Solitaire-5.471 (a); Z250-4.330 (ab); P60-3.418 (bc) and SureFil-2.779 (c). Thermocycling analysis showed no significant differences between the thermocycled and non-thermocycled groups for each material tested. It was concluded that no test material prevented microleakage. Only SureFil and P60 showed leakage means significantly lower than amalgam, with SureFil showing lower leakage than Solitaire. P60 only showed lower leakage than Solitaire in the thermocycled groups and Z250 showed results similar to the others materials.

Influence of adhesion promoters and curing-light sources on the shear bond strength of orthodontic brackets.

CONTEXT: The effect of different curing units on bond strength of orthodontic brackets is still unclear when utilizing nanofilled composites in comparison with traditional Transbond-XT. AIM: To evaluate the influence of two adhesive promoters and two curing-light units on the shear bond strength (SBS) of orthodontic brackets. SETTINGS AND DESIGN: The factors under study were adhesive promoters (nanofilled composite - Filtek-Z350 flowable restorative and conventional orthodontic adhesive - Transbond XT) and curing-light units (halogen lamp - Ultralux and LED device - Radii-Call). MATERIAL AND METHODS: Forty lower bovine incisors were utilized. The teeth were distributed in four groups (n = 10) according to the combination between adhesive promoters and curing-light units. Scotchbond Multipurpose-Plus and Transbond-XT primer were used to bond Filtek-Z350 Flowable Restorative and Transbond-XT, respectively. After storage in distilled water for 24 h, the brackets were subjected to SBS test at a speed of 0.5 mm/min until bracket debonding. The Adhesive Remnant Index (ARI) was assigned at fractured specimens. STATISTICAL ANALYSIS USED: Analysis of variance and Tukey test were utilized. The Kruskal-Wallis test was used to compare ARI scores between the groups (p<0.05). RESULTS: There was statistically significant difference between the adhesive promoters tested. Transbond-XT showed higher SBS means than Filtek-Z350. There was no statistically significant difference between both curing-light units tested in this study, neither between ARI scores. CONCLUSIONS: The conventional orthodontic adhesive presented higher bond strength than the nanofilled composite, although both materials interacted similarly to the teeth. The curing-light devices tested did not influence on bond strength of orthodontic brackets.

Efficacy of in-office bleaching techniques combined with the application of a casein phosphopeptide-amorphous calcium phosphate paste at different moments and its influence on enamel surface properties.

OBJECTIVES: The aim of this in vitro study was to investigate the efficacy of in-office bleaching technique combined with the application of a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (MI Paste-MI) at different moments and its influence on enamel surface properties. METHODS: Eighty bovine dental crowns were randomly allocated into eight groups (n = 10), and bleached with either 35% hydrogen peroxide (HP) or 37% carbamide peroxide (CP). Four different protocols of application of MI were considered: without MI, MI applied before bleaching, MI applied after bleaching, and MI applied both before and after bleaching. Bleaching effectiveness was measured by the VITA EasyShade spectrophotometer utilizing the CIEL*a*b* system (ΔE, ΔL*, Δa*, and Δb*). Color readings were measured at baseline, 7, 14, and 21 days. Hardness and roughness were measured at baseline (T0) and immediately after bleaching (T14). Data were subjected to the two-way ANOVA for repeated measurements and Tukey's test at 5%. RESULTS: HP groups achieved the greatest color change. The application of a CPP-ACP paste did not reduce the efficacy of bleaching peroxides. Samples bleached with CP showed decreased hardness at T14. Samples bleached with HP that received the application of MI before and before/after bleaching did not present hardness decrease at T14. Samples bleached with peroxides only and received MI after bleaching showed increased roughness at T14. CONCLUSIONS: The use of CPP-ACP was able to prevent negative changes in roughness and hardness of bovine enamel when associated to hydrogen peroxide, and might be applied before/after the bleaching protocol.

Impact of adhesive and photoactivation method on sealant integrity and polymer network formation.

We evaluated the influence of photoactivation method and hydrophobic resin (HR) application on the marginal and internal adaptation, hardness (KHN), and crosslink density (CLD) of a resin-based fissure sealant. Model fissures were created in bovine enamel fragments (n = 10) and sealed using one of the following protocols: no adhesive system + photoactivation of the sealant using continuous light (CL), no adhesive system + photoactivation of the sealant using the soft-start method (SS), HR + CL, or HR + SS. Marginal and internal gaps and KHN were assessed after storage in water for 24 h. The CLD was indirectly assessed by repeating the KHN measurement after 24 h of immersion in 100% ethanol. There was no difference among the samples with regard to marginal or internal adaptation. The KHN and CLD were similar for samples cured using either photoactivation method. Use of a hydrophobic resin prior to placement of fissure sealants and curing the sealant using the soft-start method may not provide any positive influence on integrity or crosslink density.

Preliminary clinical reports of a novel night-guard tooth bleaching technique modified by casein phosphopeptide-amorphous calcium phosphate (CCP-ACP).

Although supervised night-guard bleaching has proved successful for whitening teeth, both mineral loss and tooth sensitivity are still common problems. The present study introduces a novel remineralizer as well as describes the utilization of a possibly low sensitivity supervised night-guard vital tooth bleaching technique. A 22% carbamide peroxide gel was mixed with the casein phosphopeptide-amorphous calcium phosphate-containing MI Paste. The peroxide/MI Paste mixture was prepared with 1 ml of each material until obtaining a homogeneous paste. Five patients were instructed to follow a home bleaching protocol for 3 weeks. The outcome was assessed visually with a Vitapan scale. All subjects presented reduction of at least two Vitapan scale units after bleaching and no sensitivity was reported. The concomitant use of MI Paste and peroxide might not affect the gel effectiveness and still reduce hypersensitivity levels.

Update on nonsurgical, ultraconservative approaches to treat effectively non-cavitated caries lesions in permanent teeth.

Dental caries on tooth surfaces is still a problem in many industrialized countries. For many years, dentistry was influenced by a mechanical approach characterized by the use of high-speed rotary cutting instruments, and dentists predominantly used surgical methods to address caries. This included radical removal of diseased portions of the tooth, along with material-driven geometric extensions to areas that were assumed to be caries-resistant. This concept of extension for prevention was introduced by G. V. Black and influenced dentists for more than 120 years. Recently, a new paradigm of operative conservatism, sometimes referred to as "minimally invasive dentistry," has gained popularity. This paradigm is designed to promote maximum preservation of healthy dental structures over a lifetime. The aim of this review is to discuss the efficacy of current nonsurgical treatments for non-cavitated caries lesions in permanent teeth. Based on results obtained from clinical trials, this review evaluates treatments such as consumption of CPP-ACP added gums, resin infiltration and fissure sealing. Although in a few cases an invasive approach is needed to arrest caries progression, the non-surgical approach generally provides potential benefits that include conserving structure by delaying intervention or minimizing the operative procedure. All current non-invasive methods are effective in treating non-cavitated caries lesions. The adoption of non-invasive approaches in the management of these lesions can preserve dental tissues, thus increasing tooth longevity.

Microinfiltração em restaurações de resina composta e sua relação com o ultrassom / Microleakage of composite resin restorations and its relationship with ultrasonic devices

As microinfiltrações em restaurações de resina composta constantemente são referidas como principal motivo de insucesso do procedimento restaurador. Com a necessidade de otimizar o tempo de atendimento aos pacientes e torná-lo menos desconfortável, passou-se a utilizar os aparelhos de ultrassom como instrumentos atuantes no auxílio de procedimentos de raspagem periodontal. Este artigo discorre sobre estudos na literatura que abordam a relação entre o uso da instrumentação ultrassônica em procedimentos periodontais e as deficiências no selamento marginal das restaurações em resina composta(AU)

Microleakage of composite resin restorations is consistently reported as the main reason for failure of this restorative procedure. Ultrasonic devices have been developed to reduce patient's chair time and to make periodontal scaling procedures less uncomfortable. This article discusses studies that address the relationship between the use of ultrasonic instrumentation used for periodontal procedures and failure of the marginal sealing of composite resin restorations(AU)

Effect of irradiation times on the polymerization depth of contemporary fissure sealants with different opacities.

The aim of this study was to evaluate the depth of curing of 10 contemporary blue light-activated dental flowable materials at several opacities, influenced by different irradiation times using FT-IR spectroscopy. Fifty-five specimens (n = 5) with a 5-mm diameter and 1-mm thickness of translucent (Opallis Flow T), yellowed (Master Flow A2; Opallis Flow A2; Natural Flow A2; Fluroshield Yellowed), and opaque materials (Master Flow OA2; Natural Flow O; Opallis Flow OA3.5; Opallis Flow OP; Fluroshield White) were obtained at six curing times (10s, 20s, 30s, 40s, 50s, and 60s) using a high-intensity LED (Coltolux, Coltène/Whaledent). The degree of conversion (DC) (%) was obtained using the Nexus 470 FTIR Spectrometer (Nicolet Instruments, USA). The FTIR-ATR spectra for uncured and cured samples were analyzed using a ZnSe crystal. The top and bottom surfaces of the cured specimens were analyzed to obtain the depth of curing. Two-way ANOVA was used to analyze the data. The highest curing depth was obtained by Natural Flow OA2, while the lowest was shown by Master Flow OA2. The shortest curing time generated similar depths of cure in comparison with the most extensive for Opallis Flow A2 and Fluroshield Yellowed. Therefore, depth of curing, influenced by the irradiation time, was dependent on the materials. Using the Natural Flow OA2 opaque sealant and the 10-s curing time for Opallis Flow A2 and Fluroshield Yellowed may represent alternative approaches to sealing tooth fissures.

Microabrasão na estética dentária: sucesso com procedimento minimamente invasivo / Microabrasion in cosmetic dentistry: success with minimally invasive procedure / Microabrasion in cosmetic dentistry: success with minimally invasive procedure

Introdução A estética do sorriso tem motivado pacientes a buscarem o tratamento odontológico. Assim, apresença de manchas brancas pode causar desconforto para o paciente, necessitando de intervenção por parte do cirurgião dentista. Objetivo: Descrever a técnica de microabrasão aplicada para o tratamento estético de múltiplas lesões brancas inativas de cárie dentária, visualizadas após remoção de aparelho ortodôntico. Métodos: A microabrasão dentária foi realizada através da manipulação e aplicação de uma pasta à base de pedra pomes e ácido fosfórico a 37%. A pasta foi aplicada, sob isolamento absoluto, com taça de borracha, perfazendo um total de 6 aplicações, com duração de 15 s cada. Ao final de cada aplicação foi realizada lavagem com jato de água.Resultados: A utilização da técnica de microabrasão demonstrou resultado estético satisfatório para o tratamentode múltiplas lesões brancas inativas de cárie superficiais no esmalte dentário. Conclusões: A preservação daestrutura dentária, bem como a devolução da estética, obtidas através da microabrasão sugerem queprocedimentos minimamente invasivos devem ser sempre utilizados como a primeira opção de tratamento paralesão branca inativa de cárie que cause desconforto estético para o paciente

Introduction: The aesthetics of the smile has motivated patients to seek dental treatment. Thus, the presence ofwhite spot lesions may cause discomfort for the patient, requiring intervention by the dentist. Objective: To describe the microabrasion technique applied for the aesthetic treatment of multiple inactive white spot lesions after removal of orthodontic appliance. Methods: The dental microabrasion was accomplished through the manipulation and application of a paste based on pumice and 37% phosphoric acid. The paste was applied, under rubber dam,with rubber cup, making a total of six applications, lasting 15 seconds each. At the end of each application washingwith water jet was done. Results: The use of microabrasion technique showed satisfactory aesthetic result for thetreatment of multiple inactive white spot lesions on the enamel surface. Conclusions: The preservation of toothstructure as well as the return of aesthetics obtained by microabrasion reinforce that minimally invasive procedures should always be used as the first treatment option for inactive white spot lesions that cause aesthetic discomfort for the patient

Influence of light-curing units and restorative materials on the micro hardness of resin cements.

AIM: The aim of this study was to evaluate the effect of indirect restorative materials (IRMs) and light-curing units (LCUs) on the micro hardness of dual-cured resin cement. MATERIALS AND METHODS: A total of 36 cylindrical samples (2 mm thick) were prepared with dual-cured resin cement (Relyx ARC) photo-activated with either a QTH (Optilight Plus) for 40s or a LED (Radii) light-curing unit for 65s. Photo-activation was performed through the 2-mm- thick IRMs and the samples were divided into six groups (n=6) according to the combination of veneering materials (without, ceramic and indirect resin) and LCUs (QTH and LED). In the control group, the samples were light-cured with a QTH unit without the interposition of any restorative material. Vickers micro hardness test was performed on the top and bottom surfaces of each sample (load of 50 g for 15 secs). The data were statistically analyzed using a three-way ANOVA followed by Tukey x s post-hoc test ( P < 0.05). RESULTS: There were no statistically significant differences on the top surface between the light curing-units ( P > 0.05); however, the LED provided greater hardness on the bottom surface when a ceramic material was used ( P < 0.05). The mean hardness in photo-activated samples, in which there was no interposition of indirect materials, was significantly greater ( P < 0.01). CONCLUSIONS: It may be concluded that the interposition of the restorative material decreased the micro hardness in the deeper cement layer. Such decrease, however, was lower when the ceramic was interposed and the cement light-cured with LED.

Clareamento dentário como etapa prévia à restauração de dentes com alteração severa de cor / Dental bleaching as a step prior to restoration of severe discolored teeth

RELATO DE CASO: Paciente do gênero masculino, 30 anos, procurou serviço odontológico especializado devido à insatisfação com o escurecimento dos elementos 11 e 21. Facetas indiretas em cerâmica foram indicadas no planejamento inicial. Previamente à realização do tratamento restaurador, foi proposta a realização de clareamento dentário dos dentes escurecidos. Após o sucesso obtido pela associação das técnicas de clareamento não vital em consultório, e clareamento caseiro, foi traçado novo planejamento, pautando a realização de facetas diretas em resina composta. Assim, foram realizadas facetas em resina composta (elementos 11, 12, 21 e 22), instalação de pinos de fibra de vidro (elementos 11 e 21), além de ajuste cosmético (elemento 23), tendo como resultado principal a estética do sorriso e a satisfação do paciente. CONCLUSÃO: O clareamento dentário, como uma etapa prévia ao tratamento restaurador de dentes escurecidos, orientou a definição do plano de tratamento e contribuiu para adoção de procedimentos menos invasivos

CASE REPORT: Male patient, 30 years, looked for specialized dental service due to dissatisfaction about darkening elements #11 and #21. Firstly, indirect ceramic veneers were indicated and in order to achieve a better aesthetic result tooth whitening was secondly proposed. As soon as the combination of non-vital and home bleaching techniques succeeded, a new treatment planning was drawn approaching the use of direct composite resin veneers. Resin veneers (elements #11, #12, #21, #22), fiber post cementation (elements #11 and #21), and cosmetic adjustment (element #23) were made, resulting in smile aesthetics and patient satisfaction. CONCLUSION: Tooth bleaching as a step prior to restorative treatment of discolored teeth guided the treatment planning design and contributed to the adoption of less invasive procedures

A proporção áurea como complemento na determinação da dimensão vertical / The golden proportion as a method for the determination of complementary vertical dimension

O objetivo deste estudo foi avaliar se as medidas faciais utilizadas em métodos tradicionais para determinação da Dimensão Vertical de Oclusão estão em Proporção Áurea (1: 1,618) e, por conseguinte, se podem ser utilizadas como método complementar para determinação desta dimensão. Foram selecionados aleatoriamente pacientes entre 20 e 30 anos, da clínica de Odontologia da Universidade Estadual da Paraíba. A amostra foi composta por 30 indivíduos, sendo 15 do gênero masculino e 15 do gênero feminino. Através da análise de fotografias frontais destes indivíduos, e traçados que trespassam pontos cefalométricos, foi possível elucidar novas abordagens nos tratamentos de reabilitação oral. Em relação ao grau da DTM dos pacientes pesquisados, 63,3% (n = 19) apresentavam algum grau de DTM, sendo que 50% (n = 15) apresentavam DTM leve, 10% (n = 3) apresentavam DTM moderada e apenas 3,3% apresentavam DTM severa. O restante, 36,7% (n = 11), não apresentava sinais ou sintomas de disfunções de ATM. Podemos afirmar, através deste estudo, que em pacientes sem DTM tanto os métodos de mensuração facial como os métodos fisiológicos, como o de Litle modificado por Tamaki, são eficientes na determinação da Dimensão Vertical. Porém, em pacientes com disfunções, os métodos se mostraram imprecisos.

The purpose of this study was to evaluate whether the facial measures used in traditional methods of determination of the Occlusion Vertical Dimension are in Divine Proportion (1:1,618) and, subsequently, whether this Proportion can be used as a complementary method for determination of the dimension. For that, 20 to 30 year-old patients were selected at random from Odontology Clinics of the Paraíba State University. The sample was composed by 30 individuals, 15 of male gender and 15 female gender. Through the analysis of frontal photographs of these individuals, and the designs that trespass cephalometric points, it was possível to elucidate new approches on treatements of oral reabilitation. With regard to the degree of the Temple-mandible Disfunction, 63,3% (n=19) of the patients showed some degree of TMD, of whom 50% (n=15) showed mild TMD, 10% (n = 3) showed moderate TMD and only 3.3% showed severe TMD. The rest, 36.7% (n=11), did not show any signs or symptoms of TMA disfunctions. We can state that in patients without TMD, both the methods of facial measures and physiologic methods, such as Litle's Method modified by Tamaki, are efficient in the determination of the Vertical Dimension. However, in patients with TMD the physiologic methods were imprecise.

Influência de protocolos adesivos simplificados na resistência ao cisalhamento de bráquetes ortodônticos / Influence of simplified adhesive protocols on the shear bond strength of orthodontic brackets

O objetivo deste trabalho foi avaliar in vitro a resistência ao cisalhamento de bráquetes ortodônticos metálicos. Para isto, foram utilizados três sistemas de fixação: resina convencional ortodôntica Transbond XT- 3M ESPE, cimento resinoso Rely-X U100-3M e resina Flow Filtek Z350 XT-3M ESPE. Foram selecionados 30 dentes bovinos recém-extraídos, com esmalte, sem defeitos e sem manchas. Os dentes foram limpos individualmente e armazenados em solução de timol 0,5% em temperatura ambiente por sete dias. Logo após, foram divididos aleatoriamente em 3 grupos, cada um com 10 dentes. Foi realizada profilaxia e em seguida escolhida a área mais plana do dente para fazer o condicionamento com ácido fosfórico a 37%, aplicação do adesivo selecionado e colagem do bráquete ortodôntico com o sistema de fixação selecionado. Utilizou-se um aparelho de luz led Radii (SDI) para fotoativar o sistema de fixação durante o procedimento da colagem. Em seguida, os dentes foram submetidos ao teste de resistência ao cisalhamento, em uma máquina eletrônica de ensaios eletromecânicos SHIMADZU AG-I, (10KN), com velocidade de pressão de 0,5mm/min e carga de ruptura registrada em Megapascal (MPa). Os resultados foram submetidos a estatística, utilizando análise de variância (ANOVA) e teste de Tukey ao nível de 5%de significância. Baseado nos resultados obtidos, os bráquetes apresentaram diferença adesiva de resistência ao cisalhamento. Pôde-se concluir que a resina ortodôntica transbond XT-3MESPE mostrou ser a mais resistente ao cisalhamento dos bráquetes ortodônticos.

The purpose of this in vitro study was to test the shear bond strength of metallic brackets bonded with three different materials (Transbond XT - 3M ESPE, Rely-X U100 ? 3M ESPE and Flow Filtek Z350 XT ? 3M ESPE). Thirty extracted bovine incisive teeth with sound enamel surface were cleaned and stored in thymol 0.5% at room temperature for 7 days. After that, teeth were randomly divided into three groups. The prophylaxis was carried out, followed by choosing the plainer area of the teeth surface undergone acid etching with 37% phosphoric acid, adhesive system and bracket bonding. Led light from Radii (SDI) was used for curing. Teeth were submitted to shear bond strength test in the SHIMADZU AG-I (10K) universal testing machine at 0.5 mm/min pressure speed and the tensile strenght was measured in Mega Pascal (MPa). Data analyzed by one-way Anova and Tukey test as post-hoc test. Significant difference was found among materials and Transbond XT presented the highest shear bond strength.