Is the wood unfinished?? You can try steaming it out with a clothes iron. Drop filling with CA or clear epoxy can hide it pretty well too. It will look like part of the grain once finished.
If its on a finished uke.....I'm not sure what you could do.
I've steamed them out of finished instruments but you have to creep up on it slowly. I placed several damp paper towels over the dent and used an iron. Personally, I think dents and scratched give instruments character.
thanx guys it is on my lava fluke, the dent not that big, just wondered if it could be repaired, no problem i'll just have to call it a war wound, thanx for takin the time to reply guys