Properties of four composite veneering materials polymerized with different laboratory photo‐curing units

Abstract

This study examined properties of four composite veneering materials polymerized with two different photo-curing units for the purpose of evaluating curing performance of the combination of composite material and curing unit. Two microfilled (Dentacolor and Thermoresin LC II) and two hybrid (Cesead II and Solidex) composite materials designed for prosthetic veneer were selected. The respective light sources of the units were a xenon (Dentacolor XS) and a metal halide (Hyper L II) lamp. The composite materials were exposed with the photo-curing unit for 60 s on each side (i.e. from top and bottom). Knoop hardness, compressive strength, flexural strength, flexural modulus, water absorption and water solubility were determined according to standardized testing methods. The specimens exposed with the metal halide unit generally exhibited greater Knoop hardness number, and compressive strength and lower solubility than those exposed with the xenon unit. A microfilled material (Thermoresin LC II) cured with the metal halide unit exhibited significantly improved results for all tests as compared with the same material cured with the xenon unit.

The impact of in vitro aging on the mechanical and optical properties of indirect veneering composite resins

“…The composition of these indirect, veneering composite resin systems is similar to that of the direct composite resins, but they differ in additional polymerization. 12 The mechanical and physical properties of veneering composite resins are based on their chemical composition: resin matrix, 13,14 filler particle type, 14 filler size, 15 filler percentage, 15,16 and filler-matrix bonding (silane coupling agent). 16,17 Temperature, 17,18 environmental conditions, 19 and light intensity of 18931-rev2-figs edits 3 the polymerization unit are all important factors.…”

Depth of cure and hardness of an indirect composite polymerized with three laboratory curing units

“…The influence of high-intensity light-polymerizing units on the hardness of light-activated composites has been reported by many researchers (6,9,15). The KHN test results with the greatest values were generated with the TH and LI units, possibly signifying that these two units have higher light intensities than AL.…”

“…All the KHN testing results were considerably low when compared with those for the other indirect composites (9). It might be because of the lower filler content of the material (44.7 wt%).…”

“…Post-curing properties of composite materials can be improved generally by high-intensity polymerization. Tanoue et al (9) examined certain properties of indirect composites polymerized with different light sources, and reported that hardness and water solubility were strongly influenced by the type of laboratory light-polymerizing units. The role of the laboratory light-polymerizing unit has also been indicated for improvement of curing depth and wear resistance (5,10).…”

Depth of cure and hardness of indirect composite materials polymerized with two metal halide laboratory curing units

“…Studies have shown that one such metal halide unit improved depth of cure (10) and hardness (2,11,12) of materials. In addition, use of a metal halide unit considerably reduced water solubility (1,11) and wear of indirect composites (3).…”