Degree of Conversion of Etch-and-Rinse and Self-etch Adhesives Light-cured Using QTH or LED

Abstract

Clinical RelevanceThe effect of QTH and LED curing lights on the degree of conversion of bonding agents is material dependent. SUMMARYIn the current study, the degree of conversion (DC) of bonding agents photoactivated using QTH or LED light-curing units (LCUs) was eval- Bond-CS3) were tested. For SBMP and CSE, the primer was not used. The irradiance and spectral emission of the LCUs were obtained with a radiometer and spectrometer. The materials were placed onto the ATR cell as thin films, the solvent was evaporated (when necessary) and photoactivation was carried out for 20 seconds. The DC (%) was evaluated after five minutes (n=5 650Operative Dentistry between 420 and 520 nm (peak at 467 nm). Freelight 2 presented an emission spectrum between 415 and 520 nm, and for Bluephase, it was between 410 and 530 nm, both having a peak at 454 nm. SB2 generally showed higher DC compared with the other bonding agents. When cured using the QTH unit, the DC results were SB2=CS3>CSE>SBMP; for all LEDs, the DC results showed SB2>CSE>SBMP>CS3. For SB2, the highest DC was observed when the material was cured with Radii, while there were no significant differences among the other LCUs. CSE and CS3 showed higher DC when cured using the QTH unit, but similar results were observed among the LEDs. For SBMP, no significant differences among the LCUs were detected. In conclusion, the combination bonding agent vs curing unit had a significant effect on DC, mainly for the self-etch adhesives.

Tantalum oxide as filler for dental adhesive resin

“…The addition of 5 and 10 wt% of Ta2O5 influenced the DC compared to control group (p<0.05). However, all groups showed values above 50%, which is in agreement with the DC of the commercial adhesives in the literature 35,36) . The addition of fillers in an adhesive resin may change the DC 37) , due to the decrease of light transmission in the filled resin matrix.…”

Influence of different shades and LED irradiance on the degree of conversion of composite resins

“…8,10 In some situations, this characteristic favors the improved DC of dental adhesives. 11 However, the influence of different irradiances on the DC of composite resins is questionable.…”

Distinct Photopolymerization Efficacy on Dentin of Self-etch Adhesives

“…The EDX data were consistent with the Raman results. Previous studies have indicated a close relationship between DCs and bonding strengths of adhesives to dental hard tissues (Kanehira et al, 2006;Faria-e-Silva et al, 2010). A high DC may also reduce permeability of the bonding assembly (Cadenaro et al, 2005) and increase interfacial durability and resistance to degradation (Navarra et al, 2009).…”