Buying some dental floss last weekend and ran across "DenTck" Easy Brush. These little brushes are used instead of dental floss and to clean under and around dental work. I took one look and said I bet that would be good to clean cart air holes. I picked up a small pack and they are perfect for the task. Several companies make them and they even come in different sizes. Looks like all sizes will work on a cart. Just passing it along.