Both. But they are not enough. Sometimes you still have to be clever. blabla....

with pure dedication to your work you will be more focused hence more self confident to your work, so according to me dedication is more essential than self confidence

I think both are quite important but what's more closer to my heart is "Self Confident". Because with it you can achieve what so ever your dreams are. And truth me, it can definiately lead someone to a massive success beyoug imagination.

In my opinion, dedication to success.