Cure behaviour of visible light-activated pattern materials.
OBJECTIVE
This study tested the hypothesis that the cure behaviour (depth of cure and polymerization contraction) of light-activated pattern materials was no worse than that of light-activated composite resins, allowing them to be handled in a similar fashion.


METHODS
Depth of cure was measured by a penetrometer method.


RESULTS
Cure depths were comparable to those of composite resins, ranging from 3.52 mm (Lumin-X paste) to 6.76 mm (Visioform) after visible light activation for 30 s. There were significant differences in the depth of cure of the three materials tested (P < 0.001). Polymerization contraction was assessed by a minimal load transducer method. Values ranged from 0.45% (Lumin-X paste) to 1.89% (Visioform), lower than that of composite resins. There were significant differences in the polymerization contraction values for each of the three materials (P < 0.001).


CONCLUSIONS
It was concluded that light-activated pattern materials cure in a manner comparable to composite resins, and may be built up incrementally in a similar fashion.
Whitworth
J M
JM
University of Newcastle-upon-Tyne Dental School, UK.
Makhani
S H
SH
McCabe
J F
JF
D000704:Analysis of Variance; D003188:Composite Resins / Q000737:chemistry; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000379:methods*; D008027:Light; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry
D003188:Composite Resins; D008689:Methacrylates; D011108:Polymers; D011140:Polyurethanes; C029824:urethane dimethacrylate luting resin