Crest Plus Cavity Protection toothpaste helps stop cavities before they start. Crest Cavity Protection Toothpaste gives you a cavity treatment that helps take care of your mouth by protecting your teeth and exposed roots. Regular brushing can help protect your teeth and strengthen weak spots to help fight cavities. Plus it'll leave your breath feeling fresh. Instructions: Adults and children 2 years older: Brush teeth thoroughly after meals or at least twice a day or use as directed by a dentist.