The Role of ED Primer on Polymerization of Panavia F

Objectives: This study investigated the role of ED Primer on the polymerization of Panavia F (Kuraray). Methods: The conversion reaction was monitored using real-time infrared spectroscopy with attenuated total reflectance device. The cement was mixed, placed onto the device, covered with a Mylar strip and then with a resin composite disc, and light-activation was performed for 20 s (dual-cured). A self-cured group was also obtained. Similarly, dual and self-cured groups were evaluated after mixing 0.1 µL of ED Primer with the luting material. One scan every 6 s was obtained (1665–1580 cm^-1 range, resolution of 4 cm^-1) during 1 h of monitoring, and the degree of conversion (DC, %) for each scan was calculated. Non-linear regression was used for fitting the polymerization kinetics curve, and the maximum rate of polymerization (Rp^max) calculated. Results: For the dual-cured mode, the most significant effect of ED Primer was to reduce the Rp^max, with only slight additional conversion of C=C. For the self-cured mode, the ED Primer showed to be essential for polymerization of Panavia F: without ED Primer, the reaction only started after approximately 500 s, with a final DC of 50%, whereas a continuous increase in DC was observed for the group mixed with ED Primer, with a final DC of 74%. Conclusion: ED Primer is essential for proper polymerization of Panavia F; the luting material becomes independent of the light when ED Primer is used.

This study was supported by FAPESP/Brazil, Grants # 2007/00998-0 and 2007/01006-1.