[The effect of different curing methods on the rate of base resin shrinkage]
OBJECTIVE:On the base of resin characters,the relation between the fit of deture base and curing ways was discussed.METHODS:Four resins and three processing techniques were evaluated in this study to measure the polymerization shrinkage and discuss the effect of different curing methods on base resin shrinkage. The processing techniques were conventional hot water curing method,microwave curing and microwave compression curing method. RESULTS:(1)The processing of hot water curing is long, though the linear shrinkage is the smallest.The shrinkage of each resin differs.It aslo shows great deformability. (2)Microwave curing is faster. Studies indicate that it is easy to produce porosity in the interior of the resin by mononer releasing quickly,and greater shrinkage was observed in polymerization than conventional hot water. (3)Microwave compresion curing method is cleaner and faster too. There's little difference among the resins and this system can produce a more homogeneous deture base and reduce porosity. But it has the greatest shrinkage. CONCLUSION:All of the data revealed that different curing methods have great influence on the shrinkage of base resin composites.
Ouyang
F J
FJ
Prosthodontics Department,School of Stomotology,Shanghai Second Medical University. Shanghai 200011,China.
Zhang
J Z
JZ