In reply to Mina Moheb If you're using bioceramics not much (depending on what fluid is in the canal). But if you're using a hydrophobic sealer then you won't have any adaptation to the walls and will likely have additional leakage. However, even with bioceramics you should try to use one or two paper points. You get additional information such as where the end of the root is and whether all bleeding has stopped and the canal is clean. So, there's more than one reason for using a paper point. 
Cheers.