Up to about 2 you don't need toothpaste. Once he reaches that age, any toothpaste by a well know brand will be fine.
At the moment you can use a soft face cloth to clean the tooth, or any small specially made toothbrush. Have 2 toothbrushes. One for you to use & one for him to play with, it will get him used to the sensation of the toothbrush in his mouth & should help ease the way for tooth brushing when he needs it.