There are many simple things that one can do to prevent cavities:
Fluoride: Fluoride is a naturally occurring mineral that helps prevent cavities. Fluoride can even reverse the earliest stages of tooth damage — by helping the teeth repair themselves. Due to its benefits for cavity prevention, fluoride is now added to many public water supplies. It’s also a common ingredient in toothpaste and mouth rinses.
Practice daily home care: A highly fluoridated toothpaste (PreviDent) may be commended for you if you are very prone to dental decay. Always use a soft-bristled toothbrush that fits your mouth comfortably. Consider using an electric or battery-operated toothbrush, especially if you have arthritis or other problems that make it difficult to brush effectively. Floss; gently pull the floss from the gum line to the top of the tooth to scrape off plaque. Rub the floss against all sides of the tooth. If it’s hard to manipulate the floss, use a floss holder or an interdental cleaner — such as a dental pick or stick designed to clean between the teeth.
Minimize sugar and acid: Minimize sweets over periods of the day. It may not be quantity but frequency of the sugar intake that causes decay. Beware of sugar content in foods – e.g chips, milk, pasta sauce and fruit juice. Try using sugar substitutes in coffee and tea.
Dental checkups: Keep your regular dental checkups, at least every 6 months. Have appropriate radiographs (x-rays) taken for early detection, removal of decay and to receive professional fluoride treatments