introduction: discoloration of resin composites is a common reason for replacement of these restorations. the aim of this study was to eva-luate the influence of different light curing de-vices on color stability of a microhybrid resin composite. materials and methods: 80 disc-shaped speci-mens (8 mm in diameter, 2-mm height) were fabricated from filtek z250 resin composite. specimens were divid...

PURPOSE To evaluate the curing depth and compressive strength of dental composite using halogen light curing unit and light emitting diode light curing unit. MATERIALS AND METHODS Eighty cylindrical composite specimens were prepared using posterior composite P60(3M). Forty specimens, out of which 20 samples (group A) cured with halogen light and 20 samples (group B) cured using light emitting...

AIM The purpose of this study was to compare the surface hardness of a hybrid composite resin polymerized with different curing lights. METHODS AND MATERIALS Two 3.0 mm thick composite resin discs were polymerized in a prepared natural tooth mold using: (1) a conventional quartz-tungsten halogen light (QTH- Spectrum 800); (2) a high-intensity halogen light, Elipar Trilight (TL)-standard/expon...

Dental chair lights have been known to rapidly polymerize lightcured composites beyond the point of workability. Often in our dental clinics we are advised to switch off the dental chair light while light curing of dental composites. The purpose of this study was to determine whether the dental chair light causes any effect on the degree of polymerization of light cured composites using the qua...

objectives: the aim of this in-vitro study was to assess the thermal effect of light emitting diode (led) light curing unit on the enamel etching time. materials and methods: three treatment groups with 15 enamel specimens each were used in this study: g1: fifteen seconds of etching, g2: five seconds of etching, g3: five seconds of etching plus led light irradiation (simultaneously). the micro ...

objective: the aim of the present study was to compare microtensile bond strengths (μtbs) of glass fiber posts to different parts of intra-radicular dentin using conventional method and one-shot technique under different light intensities. materials and methods: twenty-eight single-rooted teeth were prepared to receive fiber posts: group 1: conventional method at light intensity of 600 mw/cm2; ...

The purpose of this study was to assess the effect of light-tip distance on the shear bond strength and failure site of brackets cured with three different light curing units: a high-intensity halogen (Astralis 10, 10-second curing), a light-emitting diode (LED, e-Light, six-second curing), and a plasma arc (PAC System, four-second curing). One hundred and thirty-five bovine permanent mandibula...

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...

background and aims. today light cured composites are widely used. physical and mechanical properties of composites are related to the degree of conversion. light curing unit (lcu) is an important factor for composite polymerization. aim of this study is evaluation of composite resins hardness using halogen and led light curing units. materials and methods. in this study, 30 samples of filtek z...

The potential ocular hazards associated with the use of dental curing lights were evaluated. Recommendations are provided for precluding exposure of personnel to hazardous levels of optical radiation. Users should not stare directly into the dental curing lights at distances shorter than 25 cm (which would not be a likely event). Eye protectors which filter wavelengths below 500 nm may be desir...