Surface Topography, Gloss and Flexural Strength of Pressable Ceramic After Finishing-Polishing Protocols.

This study evaluated the effect of different finishing-polishing protocols on surface roughness, gloss, morphology and biaxial flexural strength of pressable fluorapatite glass ceramic. Thirty ceramic discs (12x1 mm) were produced and divided into five groups (n=6): CT: control (glaze); DA: fine grit diamond bur; DG: DA + new glaze layer; DP: DA + felt disk with fine grit diamond paste; DK: DA+ sequential polishing with silicon abrasive instruments, goat hair brush and cotton wheel. The specimens were analyzed for surface roughness (Ra) under profilometry and atomic force microscopy (AFM). Gloss was measured with spectrophotometry and micromorphology with scanning electron microscopy (SEM). Flexural strength was assessed by biaxial flexural strength test. Data were analyzed using one-way ANOVA and Tukey's post hoc test (a=0.05). DK showed the lowest surface roughness values and DA presented the highest in the perfilometer analysis. No significant differences were observed in the AFM for the CT, DG and DK groups, which presented the lower surface roughness; DA and DP had the higher Ra values. The DA, DP and CT showed the lowest surface gloss values, and the reflectance was significantly different from those observed for DK and DG groups. SEM analysis revealed the smoothest surface for DK group, followed by DG and CT groups; DA and DP groups exhibited variable degrees of surface irregularities. No significant differences were observed among groups for the biaxial flexural strength. The polishing protocol used in DK group can be a good alternative for chairside finishing of adjusted pressable fluorapatite glass ceramic surfaces.

Effect of acidic drinks on shade matching, surface topography, and mechanical properties of conventional and bulk-fill composite resins.

STATEMENT OF PROBLEM: Posterior composite restorations may be negatively affected by acidic and colored drinks. Little information is available about the effect of acidic drinks on bulk-fill composite resins. PURPOSE: The purpose of this in vitro study was to investigate the effect of acidic drinks on the different properties of conventional and bulk-fill composite resins. MATERIAL AND METHODS: A conventional composite resin and 2 representative bulk-fill composite resins were used to prepare disk-shaped specimens. The degree of conversion (DC) was monitored by spectroscopy (n=5). The specimens were divided into 5 groups: control, artificial saliva, acai juice, red wine, and Coca-Cola and were maintained for 30 days of challenge (3 periods of 15 min/d). Surface topography parameters were measured by interferometry (n=5). Elastic modulus (E) and Vickers hardness (VH) were determined by microhardness dynamic indentation (n=5). Diametral tensile strength (DTS) was determined at 0.5 mm/min (n=5). Shade matching was evaluated by using the Vitapan Classic Shade Guide. The DC, Sa, Ssk, Sku, Sdq, and DTS were statistically analyzed using 2-way ANOVA, followed by the Tukey HSD tests. E and VH were statistically analyzed by 3-way ANOVA, followed by Tukey HSD tests (α=.05). Shade matching was analyzed with the Kruskal-Wallis test. RESULTS: DC values were similar for the immediate evaluation and after 24 hours, regardless of the composite resin (P<.05). All surface topography parameters increased significantly after the acidic drinks and were greatest for Coca-Cola. The E, VH, and DTS decreased significantly for all composite resins tested (P<.05). Acai juice and red wine produced more surface staining than Coca-Cola. CONCLUSIONS: Acidic drinks negatively influenced the physical and mechanical properties of conventional and bulk-fill composite resins.

Surface topography, gloss and flexural strength of pressable ceramic after finishing-polishing protocols

Abstract This study evaluated the effect of different finishing-polishing protocols on surface roughness, gloss, morphology and biaxial flexural strength of pressable fluorapatite glass ceramic. Thirty ceramic discs (12x1 mm) were produced and divided into five groups (n=6): CT: control (glaze); DA: fine grit diamond bur; DG: DA + new glaze layer; DP: DA + felt disk with fine grit diamond paste; DK: DA+ sequential polishing with silicon abrasive instruments, goat hair brush and cotton wheel. The specimens were analyzed for surface roughness (Ra) under profilometry and atomic force microscopy (AFM). Gloss was measured with spectrophotometry and micromorphology with scanning electron microscopy (SEM). Flexural strength was assessed by biaxial flexural strength test. Data were analyzed using one-way ANOVA and Tukey's post hoc test (a=0.05). DK showed the lowest surface roughness values and DA presented the highest in the perfilometer analysis. No significant differences were observed in the AFM for the CT, DG and DK groups, which presented the lower surface roughness; DA and DP had the higher Ra values. The DA, DP and CT showed the lowest surface gloss values, and the reflectance was significantly different from those observed for DK and DG groups. SEM analysis revealed the smoothest surface for DK group, followed by DG and CT groups; DA and DP groups exhibited variable degrees of surface irregularities. No significant differences were observed among groups for the biaxial flexural strength. The polishing protocol used in DK group can be a good alternative for chairside finishing of adjusted pressable fluorapatite glass ceramic surfaces.

Resumo O objetivo deste estudo foi avaliar o efeito de diferentes protocolos de acabamento e polimento na rugosidade da superfície, brilho, resistência à flexão biaxial e morfologia de cerâmica prensada. Trinta discos de cerâmica (12x1 mm) foram produzidos e divididos em cinco grupos (n=6): CT- controle (glaze); DA- ponta diamantada de granulação fina; DG: DA + nova camada de glaze; DP: DA + disco de feltro com pasta de diamante de granulo fino; DK: DA + polimento sequencial com instrumentos abrasivos de silício, escova de cabra e roda de algodão. Os espécimes foram analisados quanto à rugosidade da superfície (Ra) sob profilometria e microscopia de força atômica (AFM). O brilho foi medido com espectrofotometria e a micromorfologia com microscopia eletrônica de varredura (SEM). A resistência à flexão foi avaliada pelo teste de resistência à flexão biaxial. Os dados foram analisados ​​usando ANOVA um fator e teste post hoc de Tukey (a=0,05). DK mostrou mais baixos valores de rugosidade da superfície e DA apresentou o maior na análise do perfilômetro. Não foram observadas diferenças significativas no AFM para os grupos CT, DG e DK, que apresentaram a menor rugosidade de superfície; DA e DP apresentaram os maiores valores Ra. O DA, DP e CT mostraram valores de brilho superficial mais baixos, e a reflectância foi significativamente diferente da observada para os grupos DK e DG. A análise de SEM revelou a superfície mais homogênea para o grupo DK, seguido de grupos DG e CT; Os grupos DA e DP exibiram graus variáveis de irregularidades da superfície. Não foram observadas diferenças significativas entre os grupos quanto à resistência à flexão biaxial. O protocolo de polimento utilizado no grupo DK pode ser uma boa alternativa para o acabamento em consultório das superfícies de cerâmicas prensadas após ajustes.

Reabilitação estética do sorriso por meio de procedimento restaurador direto com resina composta nanoparticulada: relato de caso / Esthetic smile rehabilitation throught direct restorative procedure with nanoparticulate composite resin: a case report

Pacientes acometidos por traumas em dentes anteriores são comumente encontrados na prática clínica. Estes traumas ocasionam diversas complicações, que podem prejudicar a função como fonética, estética e em casos mais graves, até resultar em perda do elemento dentário. Na ocorrência de fraturas dentárias, uma das alternativas de reabilitação é o procedimento restaurador por meio de técnica direta, com utilização de resina composta. Tais materiais possuem facilidade na execução da técnica, apresentam baixo custo, quando comparado às restaurações indiretas e ainda possuem propriedades físicas e mecânicas que são semelhantes à estrutura dentinária, funcionando de forma a biomimetizar a estrutura perdida do elemento dentário. O presente caso clínico relata reabilitação funcional e estética do sorriso de um paciente jovem, por meio de procedimento restaurador direto, o qual foi possível devolver aspecto de naturalidade aos dentes e harmonia do sorriso.

Patients affected by injuries in anterior teeth are commonly encountered in clinical practice. These cause a variety of complications, which may impair the function as phonetics, esthetics and in more severe cases, even result in dental element loss. On dental fractures occurrence, one of the rehabilitation alternatives is the restorative procedure through direct technique, using composite resin. Such materials have ease in execution of the technique, feature low cost, when compared to the indirect restorations and still possess physical and mechanical properties, which are similar to dentin structure, working in order to resemble the lost dental element structure. The present clinical case reports functional and esthetic smile rehabilitation of a young patient, through direct restorative procedure, which was possible return aspect of naturalness to the teeth and the smile harmony.

Reabilitação estética do sorriso com laminados cerâmicos: Relato de caso clínico / Aesthetic Restabilishment with laminates venners: Case report

Resumo: A busca por um sorriso harmônico eleva o nível de exigência e a expectativa dos pacientes. Esse fato propicia o desenvolvimento de novos materiais e técnicas odontológicas que visam procedimentos conservadores e resultados mais previsíveis. As cerâmicas têm se tornado alternativa para essas reabilitações de alta exigência estética, uma vez que possuem propriedades como biocompatibilidade, estabilidade de cor, longevidade e resistência, ou seja, apresentam biomimetismo com esmalte. Dessa forma, esse relato de caso tem como objetivo descrever a sequência clínica de uma reabilitação estética dos dentes 11, 12, 21 e 22 empregando laminados de cerâmica vítrea a reforçadas de dissilicato de lítio, proporcionando a reprodução das características naturais dos dentes. Os laminados cerâmicos promoveram excelentes resultados estéticos, sendo que o conhecimento da técnica operatória e dos materiais restauradores e qualidade do trabalho protético são essenciais parao planejamento e execução de restaurações estéticas.

The search for a harmonious smile raises the level of demand and the expectations of patients. This fact enables the development of new dental materials and techniques to conservative procedures and more predictable results. The ceramic has become an alternative to these highly demanding aesthetic restorations since they possess properties such as biocompatibility, color stability, durability and resilience, ie with the present biomimetism tooth structure. Thus, this case report aims to describe the clinical sequence of an aesthetic rehabilitation of the teeth 11, 12, 21 and 22 using laminated glass-ceramic reinforced of lithium di-silicate, providing playback of the natural characteristics of the teeth. The ceramic laminates promoted excellent aesthetic results, and the knowledge of the surgical technique and restorative materials and quality of the prosthetic work areessential for planning and execution of esthetic restorations.

Acabamento e polimento em resina composta: reprodução do natural / Polishing composite resin: reproduction of natural

As restaurações diretas em resina composta em dentes anterioresconstituem tratamento estético, entretanto, dependendo da composição e do uso inadequado destes compósitos resinosos, podem resultar em restaurações insatisfatórias provenientes da inadequada rugosidade superficial, porosidade, ausência de brilho e alteração de cor. Estas características podem ser evitadas ao se realizar adequado acabamento e polimento. Diante deste quadro, este artigo tem como objetivo apresentar uma técnica de acabamento e polimento para restaurações em resina composta. O acabamento e polimento é uma etapa imprescindível para a harmonia do sorriso e sucesso das reabilitações com resina composta.

Direct composite resin restorations in anterior teeth are aesthetic treatment, however, the some composition and the inappropriate use of these resin composites can be result in unsatisfactory restorations from inadequate surface roughness, porosity, lack luster and color change. These characteristics can avoid when management correct finishing and polishing. The aim of this article was to describe finishing and polishing techniques in composite resin restorations. The finishing and polishing is essential to smile harmony and success of restorations with composite resin step.

Does bonding to dentin reduce microleakage of composite restorations?

This study evaluated the effect of adhesive application only to enamel on the marginal microleakage of composite resin restorations performed with different adhesive systems. Standardized cylinder-shaped cavities were prepared on the buccal surface of eighty bovine incisors. Two etch-and-rinse (Adper Scotchbond Multi-purpose [3M ESPE, St. Paul, MN USA] and Adper Single Bond 2 [3M ESPE]) and two self-etching (Clearfil SE Bond [Kuraray, Osaka, Japan] and Adper Prompt [3M ESPE]) adhesive systems were evaluated. The adhesives were applied only to enamel or to both dentin and enamel. After adhesive light-activation, the cavities were restored with composite resin. The samples were coated with two layers of nail polish, except an area of 1-mm wide around of the restoration, and immersed in a methylene blue solution. Afterwards, the specimens were ground in order to obtain powder which was immersed in absolute alcohol. The solutions were centrifuged and the supernatant was analyzed using an absorbance spectrophotometer. Linear regression was used to estimate the dye concentration. Data were analyzed using ANOVA and Tukey's tests (alpha = 0.05). The etch-and-rinse adhesives showed lower microleakage means compared to those of the self-etching adhesives. Adper Prompt presented higher microleakage means. There was no difference between the modes of application of the adhesive on the cavity for all adhesive systems, except for Clearfil SE Bond. This showed lower microleakage when applied to the whole cavity. Bonding to dentin may not reduce microleakage of composite restorations.

Effect of acid etching time and technique on bond strength of an etch-and-rinse adhesive.

The aim of this study was to evaluate the effect of acid etching time and technique on bond strength of a two-step etch-and-rinse adhesive system to dentin and enamel. Thirty human third molars were mesio-distally sectioned, parallel to the long axis of each tooth, in two halves. Buccal/lingual surfaces were abraded to obtain both flat exposed enamel and dentine. The etchant was applied with and without the use of dispensing tips provided by manufacturer. When the tip was not used, the etchant was agitated (active) over the substrate or left undisturbed (passive). The etchings were done for 15 or 30s. After rinsing the acid, the adhesive XP Bond (Dentsply Caulk, Milford, DE, USA) was applied and light-cured. Resin composite cylinders were built up on dentin and enamel substrates. A shear load was applied to the samples at a crosshead speed of 0.5 mm/min until failure. Data were statistically analyzed by three-way ANOVA and Tukey test (alpha = 0.05). There was no difference between the etching techniques in bonding to enamel. Application with the tip or active without the tip promoted higher bond strength to dentin than passive application. Extending the etching time reduced the bond strength to dentin and did not alter the values for enamel. The passive application without tips produced the lowest bond strength when the etchant was applied for 15s. All techniques demonstrated similar values for application during 30s. The acid etching time and technique significantly influence the bond strength of etch-and-rinse adhesive to dentin.