What kind of toothpaste best prevents or slows caries?

Fluoride. Fluoride is a natural cavity fighter which helps to strengthen tooth enamel and fight tooth decay. Not every toothpaste contains fluoride. You should use toothpaste which contains this cavity-fighting mineral.
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1.1 % NaF toothpaste. For reminrralization you need to add 1.1% Neutral Sodium Fluoride 5000 ppm and Calcium to your teeth. MI paste, Prevident or Fluoridex. .
Caries control. OTC t'paste w ADA seal of approval has appropriate anti-cavity activity. If decalcified areas present, your Dentist can prescribe appropriate remineralizing medicaments. T'paste must be coupled with appropriate brushing technique, cleaning between teeth where t'brush cannot reach, a diet that does not encourage cavity producing bacteria, and regular professional care.