Panavia F: the role of the primer

This study evaluated the rate of polymerization (R(p)) and degree of conversion (DC) of Panavia F when self- or dual-activated, and the influence of either using or not using a primer containing co-initiators (ED Primer) mixed with the material. The conversion reaction was monitored using real-time infrared spectroscopy with an attenuated total reflectance device. The cement was mixed, put onto the device and irradiated for 20 s (dual-cured). A self-cured group was also prepared. Similarly, dual- and self-cured groups were evaluated after mixing ED Primer with the cement. The DC was monitored for 1 h and the R(p) was calculated. For the dual-cured mode, the most significant effect of ED Primer was to reduce the R(p)(max). For the self-cured mode, the primer was shown to be essential for polymerization of Panavia F: without ED Primer, the reaction started only after approximately 500 s, with a final DC of 50%, whereas a continuous increase in conversion was observed for the group mixed with ED Primer, with a final DC of 74%. The ED primer is essential for proper polymerization of Panavia F; the cement becomes independent of the light when the primer is used.