BACKGROUND Modern dental composite restorations are wholly dependent on the use of Visible Light Curing devices. The characteristics of these devices may influence the quality of composite resin restorations. OBJECTIVE To determine the characteristics of light curing units (LCUs) in dental clinics in Nairobi and their effect on light intensity output, depth of cure (DOC) and surface micro-har...

PURPOSE Adequate polymerization is a crucial factor in obtaining optimal physical properties and a satisfying clinical performance from composite resin materials. The aim of this study was to evaluate the polymerization efficiency of dual-cure resin cement cured with two different light curing units under zirconia structures having differing thicknesses. MATERIALS AND METHODS 4 zirconia discs...

The aim of this study was to evaluate the effects of different light-curing units and resin cement curing types on the bond durability of a feldspathic ceramic bonded to dentin. The crowns of 40 human molars were sectioned, exposing the dentin. Forty ceramic blocks of VITA VM7 were produced according to the manufacturer's recommendations. The ceramic surface was etched with 10% hydrofluoric aci...

The aim of this study was to assess polymerization ability of three light-curing units by evaluating the influence of the light source, curing regimen and permeant (water or ethanol) on sorption, solubility and amount of residual monomers of a dental adhesive. Specimens of Adper Single Bond 2 were fabricated using a stainless steel circular matrix (8 mm x 1 mm). One quartz-tungsten-halogen (QTH...

The aim of this in vitro study was to evaluate the influence of light-curing units and different sample thicknesses on the microhardness of a composite resin. Composite resin specimens were randomly prepared and assigned to nine experimental groups (n = 5): considering three light-curing units (conventional quartz tungsten halogen [QTH]: 550 mW/cm(2) - 20 s; high irradiance QTH: 1160 mW/cm(2) -...

This study evaluated the bond strength (BS) of experimental resin cements formulated with different photoinitiators when activated by two kinds of light-curing units (LCUs) through a ceramic material. Seven resin blends with different camphorquinone (CQ) and/or phenylpropanedione (PPD) concentrations (weight) were prepared: C5: 0.5% CQ; C8: 0.8% CQ; P5: 0.5% PPD; P8: 0.8% PPD; C1P4: 0.1% CQ and...

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 ...

statement of problem: one of the factors affecting the degree of polymerization of light-cured composites is the type of light-curing unit used. in addition, physicomechanical properties of composite resins depend on the degree of conversion and polymerization. objectives(s): since the type of initiator in new composite resins is not explained by manufacturers, this study is an attempt to compa...

The study aimed at evaluating the depth of cure and knoop hardness of a microfine-hybrid composite resin that was photo-activated using different methods. A bipartite brass mold was filled with composite resin and photo-activation was performed using four methods: (1) Intermittent method using quartz tungsten halogen (QTH) light curing unit (LCU) (2) Continuous method (QTH) (3) Exponential meth...