I have a 4 years old son and I am worried about his oral health. How is tooth decay caused and how can I avoid it?

Tooth decay occurs when several factors occur simultaneously. Firstly, there must be a tooth that is susceptible to decay. Secondly, there must be dental plaque i.e. bacteria. These bacteria transform carbohydrates to acids that dissolve the tooth enamel. In addition, there has to be sufficient time for demineralisation (dissolution of the tooth enamel) to occur and insufficient time for the body's natural defence mechanism (saliva) to "remineralise" the tooth and repair any damage.

In industrialized countries dental caries appears to be less related to the diet itself and more related to individual behaviours. That means a good oral hygiene and the appropriate use of fluoride will prevent dental caries.

Our recommendations are:

• Clean teeth with fluoride toothpaste twice daily. If possible clean around the teeth with dental floss or toothpicks once a day. Do not eat after cleaning teeth at bedtime as salivary flow decreases as we sleep.
• Visit the dentist about every 6 months for a check-up.
• How often you eat and drink counts. Allow time between eating occasions for saliva to neutralise the acids. Do not nibble food or sip drinks continuously.
• Sugar-free chewing gum has been shown to be "tooth-friendly" as it helps increase saliva flow and clears food debris from the mouth.