Introduction: The present study was performed to evaluate the effects of light-curing modes and shades of methacrylate and silorane-based composite resins on temperature rise during polymerization of composite resins. Materials &Methods: In this in vitro study, ninety composite samples with two types of composite resin - methacrylate-based and a low-shrinkage silorane-based were prepared, in...

The effect of curing agent (6610) content and temperature on the rheological behavior of the epoxy resin CYD-128 was studied by DSC analysis and viscosity experiments. The results show that the resin system meets the requirements of processing technology. A complete reaction occurs when the curing agent content (40 parts per hundred resin, phr) is a little higher than the theoretical value (33....

AIM The study compared pulp temperature rise during polymerization of resin-based composites (RBCs) using halogen and LED light-curing units (LCUs). METHODS AND MATERIALS A total of 32 teeth extracted from patients aged 11-18 years were used in the study. Thermocouples placed on the roof of the pulp chamber using a novel 'split-tooth' method. In Group 1 a halogen LCU with a light intensity of...

Cold weather drastically shortens the construction season in northern regions. Low ambient temperatures are known to have detrimental impacts on reactivity and hardened performance of cementitious materials. This study therefore aims assess combined calcium silicate hydrate (C–S–H) seeds, binary chloride-free antifreeze admixture (i.e., urea nitrate), short-period precuring at room temperature ...

AIM The purpose of this study was to investigate the effect of different temperatures on the efficacy of polymerization during the insertion of composite resin using different light curing units. METHODS AND MATERIALS A total of 45 disc-shaped specimens were fabricated from Z250 composite resin (3M/ESPE, St. Paul, MN, USA) with 15 each prepared at three different temperatures (refrigerated to...

AIM The aim of this study was to evaluate the heat generation of three different types of light curing units. METHODS AND MATERIALS Temperature increases were recorded from a distance of 1 mm from a thermocouple to the tip of three different types of light curing units including one quartz-tungsten halogen (QTH), one plasma arc (PAC), and one light emitting diode (LED) unit. An experimental m...

This study presents an experimental overview for the development of photocatalytic materials based on geopolymer binders as catalyst support matrices. Particularly, geopolymer matrices obtained from different solid precursors (fly ash and metakaolin), composite systems (siloxane-hybrid, foamed hybrid), and curing temperatures (room temperature and 60 °C) were investigated for the same photocata...

In internal curing, pre-wetted lightweight aggregates (LWA) serve as internal reservoirs to supply the extra water needed by the cementitious and pozzolanic components of the concrete during their hydration processes. Due to their porous nature and reasonably high absorption capacity, the LWA can also be filled with other materials, such as phase change materials (PCMs). In this paper, three po...

A fiber optic ultrasonic system is described which monitors the cure of an epoxy resin. Ultrasound is generated using a high-power optical fiber to deliver high-energy pulses of light to the prepared surface of an aluminum mold that contains the curing epoxy resin. The generated ultrasound is detected using a local fiber optic ultrasound sensor embedded in the curing epoxy resin. The system was...

Room-temperature vulcanizing silicone and homopolymers of 2-hydroxyethyl methacrylate (HEMA) have been used to permanently inflate detachable balloons [1] . HEMA is preferred over silicone because it is less viscous and is water soluble. Goto et al. [2] described a commercially available (HEMA A, lnterventional Therapeutics, S. San Francisco, CA) polymerizing substance that includes HEMA as the...