Properties of dual‐curable luting composites polymerized with single and dual curing modes

Abstract

The purpose of this study was to evaluate the influence of visible-light exposure on water absorption, solubility and colour stability of dual-curable luting composites. Using eight dual-curable luting composites (2bond2, Bistite II, G-CERA Cosmotech II, Imperva Dual, Linkmax, Lute-It, Panavia Fluoro Cement and Variolink II), disk specimens were prepared by the following two methods: (i) dual-cured specimens; exposed with visible-light from a light-curing unit, and (ii) chemical-cured specimens; chemically polymerized without exposure. Five specimens were produced for each material and curing mode. Water absorption and solubility were determined according to standardized testing methods, and the data were compared using analysis of variance (ANOVA) and contrasts. With regard to colour stability, the colour difference (DeltaE*) values between 24 h and the other immersion periods (1, 2, 3, 4, 8, 12, 16, 20 and 24 weeks) were calculated and then analysed by repeated measure ANOVA. The dual-cured specimens exhibited significantly lower solubility values than the chemical-cured specimens except for the Lute-It material. The dual-cured Linkmax material exhibited the lowest solubility (0.51 +/- 0.01 microg mm(-3)) and the lowest DeltaE* value after 24 weeks (2.64 +/- 0.39). The dual-curable luting composites should be light-exposed after seating of restorations in order to reduce water absorption and solubility, and to improve colour stability.

Influence of Cement Shade and Water Storage on the Final Color of Leucite-reinforced Ceramics

“…Water absorption may adversely affect the color stability of a dualpolymerizing luting resin composite by changing the refractive index of the material. Water absorption is reported to be a factor affecting short-term discoloration and, in the current study, the color change on the third day resembles previous studies 17 and could be due to water absorption.…”

“…The advantage of this system over the Munsell system (hue, chroma and value) is that CIELab units are evenly spaced in terms of visual perception, so that the spectral readings can be correlated with subjective operations. 10 The color difference (ΔE) between two specimens whose color is expressed in L*, a*, b* coordinates is derived from the following equation: [12][13][14][15][16][17][18][19] …”

Termal siklusun indirekt kompozit rezin materyallerinin renk stabilitesi üzerine etkisi

“…Önceki çalışmalarda ikinci polimerizasyon sonrası artan karbon çift bağlarının renk stabilitesini arttırdığı bildirilmiştir. 30 Çalışmamızda test edilen indirekt kompozit rezin materyalleri arasında, termal siklus sonrası önemli renk değişikliği gözlenmiştir; en fazla renk değişikliğine uğrayan Solidex için bulunan ∆E=6,87 değeri, Artglass ve Signum rezin materyallerininkinden istatistiksel olarak anlamlı düzeyde yüksektir. Artglass ve Signum materyalleri ise renk değişim değeri açısından istatistiksel farklılık göstermemiştir.…”

Effects of photocuring strategy on bonding of dual-cure one-step self-etch adhesive to root canal dentin

“…For dual-cure adhesive resins, it is of paramount importance that the resin surface is irradiated with sufficient light energy to ensure a high degree of polymerization, as the latter produces good adhesion 16,17) . Light energy is a unit that encompasses two factors: intensity of the light curing unit, also referred to as power density, and the duration of light application over a given area.…”

“…For this reason, it is important to irradiate dual-cure adhesives with sufficient light energy -through the post space -to minimize the adverse effects of uncured acidic resin monomers of one-step self-etch adhesives. Besides, the mechanical properties of dual-cure adhesives were also found to be affected by curing strategies 16,17) . Bond strength to the tooth substrate (enamel or dentin) depends on the mechanical properties of the adhesive resin, which means that dual-cure adhesives should be exposed to lightversus chemical activation alone -to ensure good bond strength 18,19) .…”