Radiopacity and physical properties evaluation of infiltrants with Barium and Ytterbium addition.

Radiopaque properties in the infiltrant should be interesting for clinicians to feel more confident to indicate this treatment. Thus, the aim of this study was to evaluate the effect of the incorporation of barium and ytterbium particles on the physical properties of resin infiltrants. Groups were divided according to the addition of ytterbium oxide (Y) alone (30 or 40%) or Y with barium (YB) (15/15% or 20/20% respectively) in the Icon commercial infiltrant and in the experimental infiltrant base. Digital radiography (n=5), Microradiography (n=5), Microtomography (n=3), degree of conversion (n=5), water sorption (n=16), solubility (n=16), contact angle (n=16), flexural strength (n=16), elastic modulus (n=16) and Energy dispersive X-ray Spectroscopy (n=10) were performed. Analyses were performed using the R program, with a significance level of 5%, and microradiography and Microtomography analyses were evaluated qualitatively. In groups with 30 or 40% of ytterbium, radiopacity was higher or equal to enamel. Microradiography and Microtomography appear to have more radiopacity in groups with 40% (Y). Among the groups with no particle addition, those of the experimental infiltrant presented a higher degree of conversion than those of Icon®. In most groups, there was solubility below the ISO-recommended levels. The addition of particles resulted in higher viscosity. Groups with Icon had higher flexural strength and elastic modulus than groups with experimental infiltrant. The addition of 40% (Y) improved polymerization, had low solubility, and had greater radiopacity than enamel, however negatively affected the viscosity increasing then. Experimental groups with the base showed a higher water sorption than Icon groups.

Influence of bioactive particles and onium salt on the physicochemical properties of experimental infiltrants.

This study evaluated physicochemical properties of experimental infiltrants after addition of hydroxyapatite nanoparticles (HAp) or 58S bioactive glass (BAG) and diphenyliodonium hexafluorophosphate (DPI). The resin matrix was composed of TEGDMA/Bis-EMA (3:1), 0.5 mol% CQ, and 1 mol% EDAB. The blends received or not 0.5 mol% DPI and 10% wt BAG or HAp. Icon was used as commercial control. The groups were characterized by XRD, FT-IR spectrometry, and SEM before and after simulated body fluid (SBF) immersion for up to 7 days. Polymerization kinetics (n =3 ), water sorption and solubility (n=10), and viscosity (n = 3) were surveyed. For polymerization kinetics, the samples were polymerized for 5 min and the data were obtained from 40 s and 5 min. Statistical analysis was made using ANOVA and Tukey's test (a = 0.05). After 7 days of SBF immersion, XRD and FT-IR showed that the HAp crystalline phase was present only in the HAp groups. A lower degree of conversion (DC) and polymerization rate were observed for the Icon and BAG groups, whereas HAp showed higher values. For the BAG group, DPI increased polymerization rate and DC in 40 s. After 5 min, all groups presented DC above 80%. In groups with particles, the HAp groups exhibited higher viscosity, whereas DPI groups showed a decrease in viscosity. Icon had the highest water sorption. To conclude, BAG neither improved the physicochemical properties studied, nor did it show bioactive properties. The addition of DPI reduced viscosity caused by particle addition and also attenuated the DC decrease caused by BAG addition. The addition of bioactive particles to infiltrants should be seen with caution because they increase viscosity and may not bring major clinical improvements that justify their use. DPI might be indicated only if any component is added to the infiltrant to act as a compensation mechanism.

Radiopacity and physical properties evaluation of infiltrants with Barium and Ytterbium addition

Abstract Radiopaque properties in the infiltrant should be interesting for clinicians to feel more confident to indicate this treatment. Thus, the aim of this study was to evaluate the effect of the incorporation of barium and ytterbium particles on the physical properties of resin infiltrants. Groups were divided according to the addition of ytterbium oxide (Y) alone (30 or 40%) or Y with barium (YB) (15/15% or 20/20% respectively) in the Icon commercial infiltrant and in the experimental infiltrant base. Digital radiography (n=5), Microradiography (n=5), Microtomography (n=3), degree of conversion (n=5), water sorption (n=16), solubility (n=16), contact angle (n=16), flexural strength (n=16), elastic modulus (n=16) and Energy dispersive X-ray Spectroscopy (n=10) were performed. Analyses were performed using the R program, with a significance level of 5%, and microradiography and Microtomography analyses were evaluated qualitatively. In groups with 30 or 40% of ytterbium, radiopacity was higher or equal to enamel. Microradiography and Microtomography appear to have more radiopacity in groups with 40% (Y). Among the groups with no particle addition, those of the experimental infiltrant presented a higher degree of conversion than those of Icon®. In most groups, there was solubility below the ISO-recommended levels. The addition of particles resulted in higher viscosity. Groups with Icon had higher flexural strength and elastic modulus than groups with experimental infiltrant. The addition of 40% (Y) improved polymerization, had low solubility, and had greater radiopacity than enamel, however negatively affected the viscosity increasing then. Experimental groups with the base showed a higher water sorption than Icon groups.

Resumo O objetivo desse estudo foi avaliar o efeito da incorporação de partículas de Bário e Itérbio nas propriedades físicas de infiltrantes resinosos. Os grupos foram divididos de acordo com a adição de Itérbio puro (30 ou 40%) ou Itérbio com Bário (15/15% ou 20/20% respectivamente) no infiltrante comercial Icon e no Infiltrante experimental base. Foram realizados os testes de: radiografia digital (n=5), microradiografia Transversa (n=5), microtomografia (n=3), grau de conversão (n=5), sorção (n=16), solubilidade (n=16), ângulo de contato (n=16), resistência flexural (n=16), modulo de elasticidade (n=16) e Espectroscopia por energia dispersiva (n=10). As análises foram realizadas utilizando o programa R, com nível de significância de 5%, e os testes de microradiografia e microtomografia foram analisados qualitativamente. Nos grupos com 30 ou 40% de Itérbio, a radiopacidade foi maior ou igual ao esmalte dentário. Na microradiografia e microtomografia parece ter maior radiopacidade nos grupos com 40% de itérbio. Dentre os grupos sem adição de partículas, os do infiltrante experimental apresentaram maior grau de conversão do que os do Icon e o grupo controle experimental e com 40% de itérbio apresentaram os melhores resultados. Na maioria dos grupos, a solubilidade foi abaixo dos níveis recomendados pela ISO. A adição de particulas resultou em maior viscosidade. Os grupos com Icon apresentaram maior resistência flexural e modulo de elasticidade do que os grupos com infiltrante experimental e a quantidade de partícula aumentou a resistência e o módulo de elasticidade. A adição de 40% de itérbio melhorou a polimerização, apresentou baixa solubilidade e maior radiopacidade do que o esmalte, porém afetou negativamente a viscosidade, aumentando-a.

Effects of the Incorporation of Bioactive Particles on Physical Properties, Bioactivity and Penetration of Resin Enamel Infiltrant.

Purpose: The resinous infiltrant lacks remineralizing activity. This research aimed to develop and evaluate bioactivity, physico-mechanical properties and penetration of resin infiltrants containing Biosilicate or nanohydroxyapatite. Methods: Experimental resin infiltrant (ERI; 75/25 wt.% TEGDMA/BisEMA) was divided among the groups Pure Experimental (PE); ERI + Biosilicate 5 or 10% (Bio5; Bio10), ERI + 10% nanohydroxyapatite (Hap10), and Icon (DMG, Germany). Bioactivity was analyzed by SEM, EDS and FT-IR/ATR after soaking in SBF. Degree of conversion (DC), sorption and solubility (SO; SOL), flexural strength, modulus of elasticity (FS; E-modulus), contact angle (CA) and penetration were characterized. Extent of penetration was analyzed by treating white spot lesions (WSL) in human dental enamel samples with the infiltrants and subsequently analyzing specimens by confocal laser scanning microscopy. Data from each test were submitted to ANOVA and Tukey's tests (p < 0.01). Results: SEM, EDS and FT-IR showed the formation of precipitates and increase in the rates of Ca and P in the groups with bioactive particles, after storage in SBF. Hap10 showed higher DC and CA values than all the other groups. Groups Bio5 and Bio10 showed CA values similar to those of Icon, higher SO and SOL values, and reduction in other properties. All infiltrants were capable of penetrating into the WSLs. Conclusion: The incorporation of Biosilicate (5 or 10%) or nanohydroxyapatite (10%) into ERI induced mineral deposition on the surface and did not compromise infiltration and penetration into WSLs, however, compromising their physico-mechanical properties.

Influence of bioactive particles and onium salt on the physicochemical properties of experimental infiltrants

Abstract This study evaluated physicochemical properties of experimental infiltrants after addition of hydroxyapatite nanoparticles (HAp) or 58S bioactive glass (BAG) and diphenyliodonium hexafluorophosphate (DPI). The resin matrix was composed of TEGDMA/Bis-EMA (3:1), 0.5 mol% CQ, and 1 mol% EDAB. The blends received or not 0.5 mol% DPI and 10% wt BAG or HAp. Icon was used as commercial control. The groups were characterized by XRD, FT-IR spectrometry, and SEM before and after simulated body fluid (SBF) immersion for up to 7 days. Polymerization kinetics (n =3 ), water sorption and solubility (n=10), and viscosity (n = 3) were surveyed. For polymerization kinetics, the samples were polymerized for 5 min and the data were obtained from 40 s and 5 min. Statistical analysis was made using ANOVA and Tukey's test (a = 0.05). After 7 days of SBF immersion, XRD and FT-IR showed that the HAp crystalline phase was present only in the HAp groups. A lower degree of conversion (DC) and polymerization rate were observed for the Icon and BAG groups, whereas HAp showed higher values. For the BAG group, DPI increased polymerization rate and DC in 40 s. After 5 min, all groups presented DC above 80%. In groups with particles, the HAp groups exhibited higher viscosity, whereas DPI groups showed a decrease in viscosity. Icon had the highest water sorption. To conclude, BAG neither improved the physicochemical properties studied, nor did it show bioactive properties. The addition of DPI reduced viscosity caused by particle addition and also attenuated the DC decrease caused by BAG addition. The addition of bioactive particles to infiltrants should be seen with caution because they increase viscosity and may not bring major clinical improvements that justify their use. DPI might be indicated only if any component is added to the infiltrant to act as a compensation mechanism.

Conservative treatment of interproximal incipient caries lesions by resin infiltration

Minimally invasive dentistry is based on conservative techniques for the treatment of initial caries lesions, the so-called white spot lesions. One of the conservative maneuvers includes the use of enamel resin infiltrant: a low viscosity material that penetrates the enamel pores to stop lesion progression. Aim: Therefore, this case report aimed to describe the clinical case of a 28-year-old female patient under routine consultation, in which a radiographic examination showed the presence of two incipient caries lesions in the left upper premolars. Methods: The application of a resin infiltrating agent (Icon®, DMG ­ Hamburg, Germany) was chosen as treatment to stop caries lesions progression. Conclusion: The use of this conservative technique can be considered a promising approach for the prevention of dental tissue wear, and the resin infiltrant is considered an effective material

Can surface protection prevent the loss of hardness on dentin and composite resin surfaces exposed to erosive challenges? / ¿Puede la protección de la superficie prevenir la pérdida de dureza en las superficies de dentina y resina compuesta expuestas a erosión?

Objective: This study investigated the effect of endogenous erosion on the microhardness of dentine and a nanofilled composite resin. Procedures for preventing erosion were also studied. Materials and Methods: 90 bovine dentine specimens were divided into three groups in accordance with the method for preventing: negative control, topical application of fluoride and resin-modified glass ionomer varnish. 120 composite resin specimens were distributed into four groups, which also included a resin sealant, among the preventive procedures. Specimens were then randomly divided into three sub-groups according to the exposure to simulate gastric acid solution and subsequent remineralization: negative control, 9 and 18 cycles. Surface analysis was carried out by measuring the Knoop hardness. The data obtained were statistically analyzed using 2-way ANOVA and Tukey test. Result: The mean hardness of dentine and of the composite specimens resin exhibited lower hardness after 18 cycles. However, the resin-modified glass ionomer varnish resulted in greater values compared to the other preventive procedures. Conclusion: A resin-modified glass ionomer varnish seems to be a promising method for minimizing the damage caused by endogenous acid, but its protection can be reduced depending on the intensity of the erosive challenge.

Objetivo: Este estudio investigó el efecto de la erosión endógena sobre la microdureza de la dentina y una resina compuesta de nanorrelleno. También se estudiaron los procedimientos para prevenir la erosión. Materiales and Métodos:90 muestras de dentina bovina se dividieron en tres grupos de acuerdo con el método para prevenir: control negativo, aplicación tópica de fluoruro y barniz de ionómero de vidrio modificado con resina. Se distribuyeron 120 muestras de resina compuesta en cuatro grupos, que también incluían un sellador de resina, entre los procedimientos preventivos. Las muestras se dividieron al azar en tres subgrupos de acuerdo con la exposición para simular la solución de ácido gástrico y la remineralización posterior: control negativo, 9 y 18 ciclos. El análisis de la superficie se realizó midiendo la dureza Knoop. Los datos obtenidos se analizaron estadísticamente mediante ANOVA de 2 vías y prueba de Tukey. Resultados: La dureza media de la dentina y de la resina de muestras compuestas exhibió una dureza más baja después de 18 ciclos. Sin embargo, el barniz de ionómero de vidrio modificado con resina resultó en valores mayores en comparación con los otros procedimientos preventivos. Conclusión: Un barniz de ionómero de vidrio modificado con resina parece ser un método prometedor para minimizar el daño causado por el ácido endógeno, pero su protección puede reducirse dependiendo de la intensidad del desafío erosivo.

In vitro study of marginal, internal and proximal adaptation of implant-supported single-crown CAD/CAM restorations

Aim: This study evaluated the precision of a CAD/CAM system by measuring marginal, internal and proximal fits in implant-supported single-crown restorations. Methods: Ten models of the upper arch were made in which implants replaced the upper left premolars. For fabrication of the zirconia infrastructures, titanium bases (TiBase) were coded and scanned using a scan body. A second digital impression was made for the fabrication of prostheses. Silicone impression material was used to determine the internal clearance between the TiBase and infrastructure and between the infrastructure and crown, whose thickness was measured at three points [P1 (cervical), P2 (middle) and P3 (occlusal)] with a stereoscopic microscope at 70x and 100x magnification. One-way ANOVA for repeated measures and the Student t-test were used for the analysis of internal and marginal adaptation. Proximal contacts were analyzed qualitatively. Results: There was no significant difference between the teeth evaluated (Student's t-test; p>0.05) or between the corresponding points evaluated in either tooth (one-way ANOVA; p>0.05). Analysis of the internal clearance between the infrastructure and crown demonstrated that all points were significantly different compared to the reference standardized at 100 µm (Student's t-test p<0.0001). There was no significant difference between P1 and P2, with the thickness at these two points being lower than that obtained at P3 (one-way ANOVA, p<0.05). The proximal contacts did not coincide with the quality defined by the device. Conclusion: The system tested was unable to produce implant-supported single-crown ceramic restorations with marginal, internal and proximal fits matching the digital workflow, with the inferior fits requiring adjustment prior to cementation

Effect of Dental Erosion and Methods for its Control on the Marginal and Internal Adaptation of Restorations with Different Adhesive Systems / Efeito da Erosão Dental e de Métodos para seu Controle na Adaptação Marginal e Interna de Restaurações Confeccionadas com Diferentes Sistemas Adesivos

The dentin exposed to erosive challenges is often superficially protected to prevent progression of the lesion. This study investigated the marginal and internal adaptation of composite resin restorations made on surfaces that had first been treated with different methods for controlling erosion. Cavities with margins in dentin were prepared in bovine incisors (n=360) and were divided into three groups according to the method for controlling the erosive challenge: negative control, topical application of fluoride and resin-modified glass ionomer varnish. The specimens were then randomly divided into three sub-groups according to the exposure to simulated gastric acid solution (DES) (5% HCl, pH=2.2) and subsequent remineralization (RE): negative control, 9 and 18 cycles of DES-RE. Finally, teeth were divided into four groups, depending on the bonding agent used for composite resin restoration (n=10): conventional etch-and-rinse adhesive system (2 and 3 steps) and self-etching (1 and 2 steps). Front and internal images of the interface tooth/restoration were recorded in stereoscopic microscope (15x) to quantify the percentage of adhesive failures. Despite the promising results of the resin-modified glass ionomer varnish after 9 cycles; no protective material prevented increased internal defects after 18 erosive cycles. More continuous internal margins were noted with etch-andrinse acid systems after more intense erosion. The maintenance of internal margins in eroded substrates was positively influenced by the resinmodified glass ionomer varnish and, under the most aggressive challenge, by the use of etch-and-rinse adhesives systems. (AU)

A dentina exposta a desafios erosivos é muitas vezes superficialmente protegida para prevenir a progressão da lesão. Este estudo investigou a adaptação marginal e interna de restaurações de resina composta realizadas em superfícies que foram previamente tratadas com diferentes métodos para controlar a erosão. Cavidades com margens em dentina foram preparadas em dentes incisivos bovinos (n=360) e divididas em três grupos de acordo com o método de controle do desafio erosivo: controle negativo, aplicação tópica de flúor e verniz de ionômero de vidro modificado por resina. Os espécimes foram então divididos aleatoriamente em três subgrupos de acordo com a exposição à solução de ácido gástrico simulada (DES) (HCl a 5%, pH = 2,2) e posterior remineralização (RE): controle negativo, 9 e 18 ciclos de DES-RE. Por fim, os dentes foram divididos em quatro grupos, de acordo com o agente de união utilizado para a restauração da resina composta (n=10): sistema adesivo convencional (2 e 3 passos) e autocondicionante (1 e 2 passos). Imagens frontais e internas da interface dente/restauração foram registradas em microscópio estereoscópico (15x) para quantificar a porcentagem de falhas adesivas. Apesar dos resultados promissores do verniz de ionômero de vidro modificado por resina após 9 ciclos; nenhum material de proteção impediu o aumento de defeitos internos após 18 ciclos erosivos. Margens internas mais contínuas foram observadas com sistemas adesivos convencionais após erosão mais intensa. A manutenção das margens internas em substratos erodidos foi influenciada positivamente pelo verniz de ionômero de vidro modificado por resina e, sob o desafio mais agressivo, pelo uso de sistemas de adesivos convencionais. (AU)

Conservative Esthetic Approach of Anterior Teeth Using Minimal Intervention and Preservation of all Sound Tooth Tissue: a Case Report / Abordagem Estética Conservadora dos Dentes Anteriores Utilizando Intervenção Mínima e Preservação de Todo o Tecido Dentário Sadio: Relato de Caso

This clinical case report describes a conservative approach to a smile harmony rehabilitation performing a gingivoplasty, dental bleaching and resin-based composites to finalize the case. This clinical article describes the case report of a patient in need of an esthetic and corrective solution for the anterior teeth, which presented a disharmonic smile, in its shape and color, besides the gingival smile. As a result, gingivoplasty, dental bleaching and restoration with composite resin were done. Gingivoplasty with bone preservation was possible because there was a large volume of soft tissue, and a distance ≥ 2 mm from the bone crest to the junction cementum enamel was confirmed. Bleaching was performed with the use of associated techniques: office (Whiteness HP 35%) and supervised at-home (Whiteness Perfect 10%) bleaching were performed, and then the "buccolingual technique" using a nanocomposite resin IPS was used from a diagnostic wax-up to perform the restorative procedure for the anterior teeth. The use of minimally invasive techniques is an effective alternative for the anterior teeth rehabilitation. As in this case, the gingivoplasty, dental bleaching with associated techniques, and restorations with nanocomposites allowed satisfactory esthetic results, even more so in relation to dental preservation, mainly in young patients. (AU)

Este relato de caso clínico descreve uma abordagem conservadora de uma reabilitação para harmonia do sorriso que foi realizado com gengivoplastia, clareamento dentário e resinas compostas para finalizar o caso. Este artigo clínico descreve o relato de caso de uma paciente com necessidade de solução estética e corretiva para os dentes anteriores, que apresentava um sorriso desarmônico, em sua forma e cor além do sorriso gengival. Como resultado, gengivoplastia, clareamento dental e restauração com resina composta foram realizados. A gengivoplastia com preservação óssea foi possível por apresentar grande volume de tecidos moles e uma distância ≥ 2 mm, desde a crista óssea até a junção do cemento esmalte. Clareamento com o uso de técnicas associadas: Clareamento de consultório (Whiteness HP 35%) e caseiro supervisionado (Whiteness Perfect 10%) foram realizados, e depois, a "técnica da barreira palatina" utilizando a resina IPS Empress direta foi realizada a partir de um enceramento diagnóstico para iniciar o procedimento restaurador dos dentes anteriores. O uso de técnicas minimamente invasivas é uma alternativa eficaz para reabilitação de dentes anteriores. Como no caso, a gengivoplastia, o clareamento dental com técnicas associadas e restaurações com nanocompósitos têm permitido resultados estéticos satisfatórios, ainda mais em relação à preservação dentária, principalmente em pacientes jovens. (AU)

Reabilitação Estética Funcional de Paciente Odontopediátrico: Relato de Caso / Aesthetic and Functional Rehabilitation in Pediatric Dentistry Patient: Case Report

A cárie dentária na atualidade continua sendo um problema de saúde pública, apesar do grande avanço tecnológico e de novas técnicas para preveni-la. Esta, se caracteriza como uma doença multifatorial, infecciosa e dieta dependente. Além disso, se apresenta mais prevalente em crianças devido a maior ingestão de carboidratos e sacarose, além de falta de controle motor durante higienização. O tratamento é dividido em quatro fases: sistêmica, preparatória, reabilitadora e manutenção. Assim, este artigo tem como objetivo relatar o caso clínico de criança de 6 anos de idade acometida por cárie precoce, descrevendo o tratamento em fases, compreendendo a reabilitação com resina composta nas unidades acometidas pela cárie e mantenedor de espaço com intuito de substituir as unidades na qual foram perdidas. Ao final do tratamento proposto, a paciente demonstrou satisfeita com o resultado, o que foi possível devolver a qualidade de vida da mesma. (AU).

Currently, caries is still a major problem in public healthy, despite the great technological development and new prevention methods. The caries is a multifactorial, infectious, transmissible and diet dependent disease. It is more prevalent in kids because of their higher intake of carbohydrates and sucrose, and the lack of motor control during the toothbrushing. The treatment is divided into four stages: systemic, preparatory, rehabilitative and maintenance. Thus, this article aims to report a case about a six-year-old child affected by early childhood caries, describing the treatment phases, comprising rehabilitation with composite created in units and space maintainer to replace the missing units. At the end of the treatment, the patient showed satisfaction with the outcome, restoring the quality of her life. (AU).

Water sorption and solubility of a nanofilled composite resin protected against erosive challenges / Sorção de água e solubilidade de uma resina composta nanoparticulada protegida contra desafios erosivos

Objective: Erosive challenges are capable of demineralizing dentin and promote physical and mechanical changes in restorative materials. The present study investigates the water sorption and solubility of one nanofilled composite resin submitted to erosive challenges. It also studies procedures that can protect these surfaces. Material and Methods: 120 specimens were used. It was divided into four experimental groups according to the type of surface protection used (negative control, topical application of fluoride, resin-modified glass ionomer varnish and resin-based sealant). Subsequently, they were randomly assigned to three subgroups (n = 10), (negative control, 9 and 18 cycles of DES-RE). According to the exposure to the simulated solution of gastric acid (DES) (5% HCl, pH = 2.2) and subsequent remineralization (RE). The specimens were dehydrated until a constant mass was obtained and immersed in deionized water for 7 days, when they were weighed and submitted to a new dehydration. The values of water sorption and solubility were calculated according to the ISO 4049:2000 specifications and analyzed statistically (2-way ANOVA / Tukey, alpha = 5%). Results: The water sorption and solubility averages after 18 cycles of DES-RE were statistically higher than negative control. Independently of the erosive challenge received, the specimens protected with the resin-modified glass ionomer varnish presented a significant increase in the values of loss and mass gain in relation to the other groups. Conclusion: No control method presented promising surface protection capacity of composite resin against to erosive challenges (AU)

Objetivo: Os desafios erosivos capazes de desmineralizar o esmalte também podem promover alterações físicas e mecânicas nos materiais restauradores. O presente trabalho investigou a sorção de água e solubilidade de uma resina composta nanoparticulada submetida a desafios erosivos. Também estudou procedimentos que possam proteger estas superfícies. Material e Métodos: Foram confeccionados 120 corpos de prova. Foram divididos em quatro grupos experimentais, de acordo com o tipo de proteção superficial empregada (controle negativo, aplicação tópica de flúor, verniz de ionômero de vidro modificado por resina e selante resinoso). Após, foram aleatoriamente distribuídos em três subgrupos (n=10) (controle negativo, 9 e 18 ciclos DES-RE). De acordo com a exposição à solução simulada de ácido gástrico (DES) (HCl a 5%, pH=2,2) e posterior remineralização (RE). Os espécimes foram desidratados até obtenção de massa constante e imersos em água destilada por 7 dias, quando foram pesados, e submetidos à nova desidratação. Os valores de sorção e solubilidade foram calculados de acordo as ISSO 4049:2000 e analisados estatisticamente (2-way ANOVA /Tukey, alfa = 5%). Resultados: Independentemente do desafio erosivo recebido, os corpos de prova protegidos com o verniz de ionômero de vidro modificado por resina, apresentaram aumento significativo dos valores de perda e ganho de massa em relação aos demais grupos. Conclusão: Nenhum método de controle apresentou promissora capacidade de proteção superficial da resina composta frente aos desafios erosivos(AU)

Minimally invasive aesthetic rehabilitation in composite resin: report of two clinical cases / Reabilitação estética minimamente invasiva em resina composta: relato de dois casos clínicos

Patient demand looking for the perfect smile has been steadily growing in the last few years. Thus, these two case reports discuss some ultra-conservatives approach to achieve good esthetic results. In the first case the clinical protocol of a restorative approach is described, the cosmetic remodeling of the teeth and in the second case, the replacement of extensive unsatisfactory composite restorations. The treatment planning was based on diagnostic waxing and the making of mock-up in both cases. Teeth bleaching were also performed before restoration. To conclude, these conservative relative therapies with composite resin restorations provide an ultra-minimally invasive protocol with excellent esthetic appearances and fuction, especially for young people. (AU)

A demanda do paciente que procura o sorriso perfeito tem crescido constantemente nos últimos anos. Assim, esses dois relatos de casos clínicos discutem uma abordagem ultraconservadora para alcançar bons resultados estéticos. No primeiro caso é descrito o protocolo clínico de uma abordagem restauradora, a remodelação cosmética dos dentes e, no segundo caso, a substituição de restaurações compostas extensas insatisfatórias. O planejamento do tratamento baseouse em enceramento diagnóstico e a confecção de mock-up. O clareamento dos dentes foi realizado antes da restauração. Para concluir, essas terapias relativas conservadoras com restaurações de resina composta fornecem um protocolo ultra minimamenteinvasivo com excelentes aparências estéticas. (AU)

Can surface protection prevent damage in margins of composite resin restorations after simulated endogenous erosion?

Aim: The study investigated the effect of using surface protection agents in the adaptation of external and internal margins of restorations subjected to simulated erosion. Methods: Cavities with margins in dentin were prepared in bovine incisors (n=120). Adhesive restorations were placed using a three-step etch&rinse adhesive system and nanofilled composite resin. The specimens were divided into four groups, according to the surface protection: negative control, topical application of fluoride (TAF), resin sealant and resin-modified glass ionomer varnish (RMGI varnish). Afterwards, they were divided into three sub-groups, according to the exposure to a simulated solution of gastric acid (DES) (5% HCl, pH=2,2) and subsequent remineralization (RE): negative control, 9 and 18 cycles of DES-RE. The evaluation of the tooth-restoration interface was performed on the internal and frontal images with the aid of a stereoscopic microscope (15x), and the percentage of continuous margins without adhesive failures was quantified. Results: In the external margins, only those groups with surface protection using sealants (resin and glass-ionomer) did not exhibit a significant decrease in the percentage of continuous margins after the erosive challenges. After 18 cycles of DES-RE, the use of resin-modified glass ionomer varnish resulted in the highest percentage of continuous margins. Conclusion: It was concluded that physically covering the surfaces with a sealing agent preserved the marginal adaptation of composite resin restorations exposed to endogenous erosive challenges

Minimally invasive approach to diastema closure using lithium disilicate porcelain veneers: clinical report / Abordagem minimamente invasiva para fechamento de diastema usando laminados cerâmicos de dissilicato de lítio: relato clínico

Objective: Numerous advances in dentistry techniques and material have allowed patients to have not only a functional but also an aesthetic smile in a conservative way. This case report describes a treatment with ceramic laminates to solve the aesthetic problems of an 18-year-old male dissatisfied with his smile. Following the correct protocols, using minimally invasive abrasions, ceramic laminates, and strong adhesion between porcelain and dental enamel can provide predictable results and clinical longevity through follow-up. (AU)

Objetivo: Devido aos inúmeros avanços das técnicas e materiais odontológicos tem sido possível proporcionar ao paciente não só a função, mas também a estética do sorriso de maneira minimamente invasiva. Esse relato de caso descreve o tratamento com laminados cerâmicos para resolver problemas de um paciente de 18 anos gênero masculino insatisfeito com o seu sorriso. Seguindo os protocolos corretamente, utilizando desgastes minimamente invasivos, laminados cerâmicos, e forte adesão entre a porcelana e o esmalte dental, é possível obter resultados previsíveis e longevidade clínica mediante acompanhamento. (AU)