Smart Rinse Mouthwash Mild Mint Listerine® Smart Rinse® is a fluoride mouthwash that helps protect your child’s teeth against cavities when used twice daily after brushing. Contains Fluoride, which strengthens teeth and reduces cavities by up to 40% more than brushing alone. Fights bad bacteria, a major cause of plaque and gum disease. Goes around the whole mouth, reaching teeth, gums and tongue. It attracts and tints the bits that brushing misses, showing your child the proof in the sink. Does not contain alcohol.