Marginal microleakage of low-shrinkage composite silorane in primary teeth: an in vitro study

Background and aims. despite the increasing demand for adhesive restorations in pediatric dentistry, polymerization shrinkage and subsequent marginal microleakage remains a problem. the aim of this study was to evaluate of the sealing ability of novel low-shrinkage composite silorane in class v cavity of primary canines in comparison with three types of composite resin.materials and methods. ninety-one non-carious extracted primary canines were randomly divided in six groups (n=15). standard class v cavities were prepared on the buccal surface of each tooth that the occlusal margin was in the enamel and the cervical margin extending 1 mm below the cemento-enamel junction. the preparations were restored with the different composite materials in normal consistency with application the bonding in six groups (filtek silorane; etch + filtek silorane; z250; filtek supreme; els saremco; aelite ls). teeth were then exposed to thermal cycles (1000 cycles, 5°c and 55°c), sealed and immersed in a 0.5% basic fuchsine for 24 hours, and finally sectioned. buccolingual and mar-ginal leakage was assessed with dye penetration.results. the best seal were obtained with etch + filtek silorane (p < 0.05) and the weakest seal with z250 composite res-torations (p > 0.05). except for etch + silorane, there was no significant differences in sealing ability (p > 0.05), and in the microleakage degree at the cementum and enamel margins (p > 0.05) between the groups.conclusion. according to the results, low-shrinkage silorane composite restorations with etching the cavity provide the highest seal in primary teeth