Translucency,opalescence and fluorescence properties of six light-cured resin composites / 实用口腔医学杂志

Objective:To evaluate the translucency,opalescence and fluorescence reflection of 6 light-cured resin composites. Methods:Disks of 6 resin composites including Filtek Supreme XT-YT(XT),Filtek Supreme XT-A3B(3M),Clearfil Majesty-A3 (MJ),Gradia Direct-A3(GC),Venus-A3(VE)and Charisma Diamond-A3(CA)were prepared in the diameter of 9 mm with the thickness 2.0 mm.PR-650 spectral scanning colorimeter was used to measure and caculate translucency parameters(TP),opal-escence parameter(OP)and fluorescence reflection(FL)and to draw the fluorescence reflection curves.Results:Except XT and MJ,TP value of other resin composites were in the range of natural tooth.Only OP value of XT was in the range of natural tooth en-amel.FL value of XT was close to that of natural tooth dentin.Fluorescent peak wavelength of GC,MJ,VE and CA were in the range of natural tooth,but fluorescent peak height was higher than that of natual tooth.TP was positively correlated with OP(r =0.85,P <0.05).There was no statistic correlation between TP and FL,between OP and FL.Conclusion:The 6 resin composites can simulate optical property of natual tooth,but the opalescence of resin composites is defective.

Resinas compostas: estágio atual e perspectivas / Composite resins: current aspects and perspectives

Os conceitos de promoção de saúde, prevenção e a estética sedimentam a Odontologia atual, que atravessa um período de constante progresso. O surgimento das técnicas adesivas e materiais restauradores são um exemplo disso, devendo porém, sua aplicação clínica ser sustentada por bases científicas conseguidas por meio de pesquisas envolvendo novas técnicas e materiais. Devido a isso a resina composta foi o material mais intensamente pesquisado na última década com o intuito de melhorar suas propriedades negativas. Existem hoje no mercado diversos tipos de resinas, surgidas durante esse processo evolutivo, cada uma tendo suas indicações e limitações. As resinas mais atuais têm demonstrado, que não apenas a quantidade de carga vem sendo alvo de estudos como também seu formato, composição e distribuição, na tentativa de incrementar suas propriedades físicas e ópticas. Por isso, têm se dado bastante enfoque em diversas áreas sempre com o intuito de proporcionar aos pacientes melhores resultados estéticos, biológicos e funcionais. A nanotecnologia, que consiste na manipulação e medida de materiais na escala de abaixo de 100 nanômetros é um exemplo da exploração de novas áreas. Apesar de termos em mãos esse verdadeiro arsenal de materiais, nenhuma resina composta atingiu excelência de um material restaurador ideal. Prevêem-se para o início do milênio, melhoras consideráveis nas formulações das resinas compostas atuais e das novas que surgirão no sentido de melhorar as propriedades dos compósitos resinosos ampliando assim sua indicação.

In recent years the odontology suffered changes in some of its concepts, aesthetics and the search for conservatives treatments are part, nowadays, of the routine of the doctor’s offices and odontologic clinics. Because of this the composite resins was the material that has been more intensely searched in the last decade with intention to improve its negative properties. Types of resins, appeared during this evolutive process, each one having its indications and limitations. The most current resins have demonstrated, that not only the amount of load is theme for studies as well as its format, composition and distribution, in the attempt to develop its physical and optic properties. That is the reason why nowadays the nanotechnology, that consists of the manipulation and measure of materials in the scale below of 100 nanometers, is intensively being studied. These new materials present inorganic particles varying of 20-75nm, what diminishes the contraction of polymerization and it promotes satisfactory superficial smoothness. Although of having access to these new materials, no composite resin reached excellency of an ideal restoring material. They are foreseen for the beginning of the milenium, considerable improvements in the formularizations of current composite resins and the news that they will appear in the direction to improve the properties of the composite resins thus extending its indication.