Quantified marginal leakage of composites in vitro

In this in vitro study the marginal leakage of three composite systems--Sevriton, Consize and Isocap--has been quantified as a function of time. The method used (v.d. Veen et al., 1984) consists of the determination of the amount of nitrogen gas passing through restoration margins at 2 atm. The results show that the marginal leakage of all composites decreased strongly with time and became negligible after about 1 month. If we rank the three systems investigated according to their marginal leakage we have Consize greater than Isocap greater than Sevriton. The data suggest that water uptake and subsequent expansion of the polymers account for the leakage decrease.