Dentin pre-treatment with the CPP-ACP containing paste did not negatively affect bond strength for Clearfil SE Bond/Filtek Z250 and Filtek P90 adhesive system/Filtek P90 composite resin restorative systems and improved bond strength for the Adper SE Plus/Filtek Z250 restorative system.

The long-term color stability of composite restorations is a critical aspect of esthetic restorative procedures. Optimal Polymerization behavior of resin composite as indicated by the degree of conversion also influence on the color stability after artificial aging of composite restorations.

Extended curing time improved the conversion only for the flowable composite. The pit and fissure sealant presented lower conversion and higher plasticization than the flowable composite.

Active air-drying for 60 seconds to volatilize solvents can be necessary to increase the degree of conversion of some adhesive systems, which might be related to improved clinical performance. SUMMARYThis study evaluated the effect of five methods of solvent volatilization on the degree of conversion (DC) of nine one-bottle adhesive systems using Fourier transform infrared/ attenuated total reflectance (FTIR/ATR) analysis. Nine adhesives were tested: Adper Single

Preheating improved the DC for all tested adhesive systems. Also, it promoted a decrease of water sorption/solubility, except for the XP Bond adhesive system.

Conclusion: PPD isolated system promoted similar chemical and mechanical properties and less yellowing compared with the CQ isolated system, regardless of the LCU used.

The aim of this study was to evaluate the influence of different curing lights and chemical catalysts on the degree of conversion of resin luting cements. A total of 60 disk-shaped specimens of RelyX ARC or Panavia F of diameter 5 mm and thickness 0.5 mm were prepared and the respective chemical catalyst (Scotchbond Multi-Purpose Plus or ED Primer) was added. The specimens were lightcured using different curing units (an argon ion laser, an LED or a quartz-tungsten-halogen light) through shade A2 composite disks of diameter 10 mm and thickness 2 mm. After 24 h of dry storage at 37°C, the degree of conversion of the resin luting cements was measured by Fouriertransformed infrared spectroscopy. For statistical analysis, ANOVA and the Tukey test were used, with p≤0.05. Panavia F when used without catalyst and cured using the LED or the argon ion laser showed degree of conversion values significantly lower than RelyX ARC, with and without catalyst, and cured with any of the light sources. Therefore, the degree of conversion of Panavia F with ED Primer cured with the quartz-tungsten-halogen light was significantly different from that of RelyX ARC regardless of the use of the chemical catalyst and light curing source. In conclusion, RelyX ARC can be cured satisfactorily with the argon ion laser, LED or quartz-tungsten-halogen light with or without a chemical catalyst. To obtain a satisfactory degree of conversion, Panavia F luting cement should be used with ED Primer and cured with halogen light.

This study determined the influence of photoinitiator concentration on polymerization characteristics of experimental composites photoactivated by different methods. Composites based on BisGMA/TEGDMA and 65% of filler were prepared with the concentration of camphorquinone/amine C1-0.5%, C2-1%, C3-1.5%, and photocured using 4 methods: High-intensity (HI), Low-intensity (LI), Soft-start (SS) and Pulse-delay (PD). Were determined the degree of conversion (DC), depth of cure (DCure) and crosslink density (CLD). Data were submitted to ANOVA and Tukey's test (p < 0.05). DC and DCure revealed that there were no differences among the photoactivation methods. C3 and C2 showed higher DC than C1. The CLD evaluation revealed considerable differences among the photoactivation methods. Photoinitiator concentration is a determinant factor in the polymerization characteristics of composites. Composite with low photoinitiator concentration show decreased DC and DCure, when compared with the composites with higher concentrations. Photoactivation methods had no effect on the DC and DCure. However, photoactivation methods showed differences when CLD was tested for composites with higher concentration of photoinitiators.