The aim : This study aims to evaluate and compare the microleakage between nano
and hybrid composite.
Materials and Methods : the sample consisted of forty extracted premolars for
orthodontics purposes , class v cavities were prepared with a speci
fic dimensions on the
buccal surface. The sample divided into two groups ; group A restored by nanocomposite (
Z350) , group B restored by hybrid composite ( Z250) , after that, the samples were placed
in the incubator with thermo cycling for a month ,The samples were then immersed in 0.5
% methelyne blue dye for 24 hours , each tooth was mesial-distal sectioned vertically ,
finally, of all samples was studied using stereomicroscope to evaluated the microleakage .
Results : there was no statistical significant difference between the nano and hybrid
composite according to microleakage.