M.M.A.C Velo, G.S. Zabeu, L.F.F. Brianezzi, R.M. Maesono, L. Wang, R.F.L. Mondelli University of São Paulo, Bauru School of Dentistry, Brazil e-mail:
[email protected]
#2407031
With the recent introduction of bulk-fill resin based composite, the compositional modifications have been made to allow such bulk placement that may also change the polymerization kinetics (Al-Ahdal et al., 2015); The flowable resin composite SDR (Dentsply) is one of the first marketed composite in this classe and the use of a 4 mm thickness is possible due their higher translucency (Lassila et al., 2012) and incorporation of a photoactive group in the methacrylate resin; Filtek Supreme flow (3M/ESPE) have an “intelligent monomer” and filler selection thereby enabling bulk placement and can be recovered with at least 2 mm of universal or posterior composite (Highviscosity bulk-fill). According to the manufactures, the shades of posterior restorations are semitranslucent and low stress curing, enabling up to 5 mm depth of cure. However, the data available for these materials are currently limited.
To evaluate the polymerization properties of bulk-fill resin composites using two diferente ligth-curing protocols, in terms of polymerization shrinkage stress and degree of conversion (%DC), comparing them to standard composites (conventional condensable and flowable resin composites).
DC measurements EXPERIMENTAL DESIGN Factors (2 levels)
Resin composites Graphic
Surefil SDR flow
Filtek bulk-fill flowable
Z350 XT flow Table 1. Polymerization contraction force according to the mode of polymerization
Filtek bulk-fill Posterior restorative
Z350 XT
Light-curing protocols Pulse activation technique
Continuous technique
RESPONSE VARIABLE
Uppercase letters represent differences between lines and columns (p
