Use a horsehair brush to clean excess polish and wax from cracks and trim. The toothbrush for your mouth is made of plastic and will scratch paint, chrome and plastic. While you’re at it, always remember to keep your detailing towels, cloths, brushes and sponges separated by the chemicals you use them with. Wash them separately too. Use the same cloths for polishing, a separate one for waxing, etc. This will reduce cross contamination and give you better results.
This is a companion discussion topic for the original entry at https://www.hagerty.com/articles-videos/articles/2007/01/02/use-your-toothbrush-for-your-teeth