I use the little gum stimulator/anti-periodontal disease brushes from Oral-B that can be found at any drugstore. They work quite nicely for the pupose, and have a robust wire that can be bent into nearly any position. They do tend to shed bristles a bit if you clean with zeal, but you can use another one dry to remove any excess bristles. Good for 9 pin sockets - for anything larger like an octal, you would obviously need something of larger diameter. Good listening,
-Richard