Are they nails ??, ( I am assuming they are similar to brads and have a flattened area at the back) !! If so you can use a Dremel tool and cut off the flat part at the back then try a screwdriver, thin and small one, to pry them loose at the front !! If they are regular nails, get another nail of slightly smaller size or a nail punch and gently drive them out from back to front !! If you can get them loose enough you can pull them easily with pliers !! Use screws to put them back after restoring !!