Metodologia: discos com resina Transbond XT foram fotoativados por 10, 20 e 30 segundos com QTH (Curing light XL 3000) ou com PAC (Apollo 95E) por 1, 2 e 3 segundos. A resina composta foi analisada por meio de espectrofotometria infravermelha (FTIR) e pelo teste de dureza Knoop (KHN). A temperatura na ponta dos aparelhos foi também avaliada. Os resultados foram analisados usando ANOVA e Tuckey ...

background and aims. the aim of the present study was to compare the efficacy of quartz tungsten halogen (qth) and light emitting diode (led) curing lights on polymerization of resin composite. materials and methods. a hybrid resin composite was used to prepare samples which were cured using two qth and ten led light curing sources. twelve groups, each containing ten samples, were prepared usin...

OBJECTIVES The aim of this study was to compare the cytotoxic effects of various dental composites polymerized with two different curing units. METHODS Disc-shaped test samples of composites Filtek Z250, Filtek A110, Filtek P60, Filtek Supreme, and SDI Rok were polymerized using one quartz tungsten halogen (QTH) and one light emitting diode (LED) light curing unit (LCU), namely Optilux 501 (Q...

The aim of this study was to determine the effect of different types of composites (Filtek Z250, Esthet X and Filtek Supreme) and dentin thicknesses (0.5 or 1.0 mm) on the generation of heat during photoactivation by QTH (conventional halogen light), LED (light emitting diode), and PAC (xenon plasma light) light-curing units. Temperature changes were recorded with a thermocouple type K connecte...

Correspondence: Flávio HB Aguiar Department of Restorative Dentistry, Piracicaba Dental School, State University of Campinas, Av. Limeira, 901, Piracicaba, SP, Brazil 13414-903 Tel +55 19 2106 5340 Fax +55 19 2106 5218 Email [email protected] Abstract: The aim of this in vitro study was to evaluate the influence of light-curing units and different sample thicknesses on the microhardness of ...

The aim of this study was to evaluate: (i) the absorption of photo-initiators and emission spectra of light curing units (LCUs); and (ii) the degree of conversion (DC) of experimental composites formulated with different photo-initiators when activated by different LCUs. Blends of BisGMA, UDMA, BisEMA and TEGDMA with camphorquinone (CQ) and/ or 1-phenyl-1,2-propanedione (PPD) were prepared. Dim...

This study evaluated, using Knoop hardness test, the polymerization depth of Rely-X dual-cured resin cement activated by chemical reaction alone (control group) or by chemical/physical mode with light curing through a 1.5-mm-thick ceramic layer (HeraCeram). Bovine incisors had their buccal surface flattened and hybridized. On this surface, a rubber mould (5 mm diameter; 1 mm high) was bulk fill...

We evaluated the curing efficiency of 4 high-intensity light-emitting diode (LED) devices by assessing percentage of residual C=C (%RDB), surface microhardness (SM), depth of cure (DC), percentage of linear shrinkage-strain (%LS), and percentage of wall-to-wall contraction (%WWC). The light-curing units tested were a QTH light, the Elipar TriLight (3M/ESPE), and 4 LED devices - the Allegro (Den...

A canonically defined mod 2 linear dependency current is associated to each collection ν of sections, ν 1 , ..., ν m , of a real rank n vector bundle. This current is supported on the linear dependency set of ν. It is defined whenever the collection ν satisfies a weak measure theoretic condition called " atomicity ". Essentially any reasonable collection of sections satisfies this condition, va...