Tooth decay - Prevention 

Preventing tooth decay 

Maintaining good oral hygiene through brushing and flossing your teeth is one of the most effective ways to prevent tooth decay. You can also change your diet.


Brush your teeth at least twice a day with fluoride toothpaste. 

Ideally, brush your teeth after eating rather than before. However, do not brush your teeth for at least 30 minutes after a meal as this can damage your teeth, particularly if you have eaten food high in carbohydrates or sugar.

It is also important you brush your teeth in the right way. The following advice may help:

  • Place the head of your toothbrush against your teeth, then tilt the bristle tips to a 45-degree angle against the gumline. Move the brush in small circular movements, several times, on all surfaces of every tooth
  • Brush the outer surfaces of each tooth, upper and lower, keeping the bristles angled against the gumline
  • Use the same method on the inside surfaces of all your teeth
  • Brush the biting surfaces of the teeth
  • To clean the inside surfaces of the front teeth, tilt the brush vertically and make several small circular strokes with the front part of the brush
  • Brushing your tongue will help freshen your breath and will clean your mouth by removing bacteria
  • Do not rinse your mouth with water or mouthwash after brushing as this washes the protective toothpaste away. Just spit out excess toothpaste

It is important to replace your toothbrush on a regular basis because they wear out and become less effective in removing plaque. Most toothbrushes need to be replaced every two to three months.

If you are considering buying an electric toothbrush, studies have shown the most effective type is one in which the head has a rotating oscillation action  meaning the head spins one way and then the other. As with manual toothbrushes, you need to replace the head of your electric toothbrush every two to three months.


Flossing is an important part of oral hygiene. It removes plaque and food particles from between your teeth and under the gumline  areas a toothbrush can not always reach. You should clean between your teeth at least once a day with floss.

Your dentist or hygienist can advise you on flossing techniques, but the following tips may help:

  • Break off about 45cm of floss or dental tape and wind most of it around one of your middle fingers. Wind the remaining floss around the same finger of the other hand. As you use the floss, you will take up the used section with this finger
  • Hold the floss tightly between your thumb and forefingers, with about an inch of floss between them, leaving no slack. Use a gentle rocking motion to guide the floss between your teeth. Do not jerk the floss or snap the floss into the gums
  • When the floss reaches the gumline, curve it into a C-shape against one tooth until you feel resistance
  • Hold the floss against the tooth. Gently scrape the side of the tooth, moving the floss away from the gum. Repeat on the other side of the gap, along the side of the next tooth
  • Keep to a regular pattern when you floss your teeth, which should help make sure you do not miss any food particles


Using dental mouthwash that contains fluoride can also help prevent tooth decay. However, this should not be used directly after toothbrushing. Choose a separate time to use mouthwash, such as after lunch. Do not eat or drink for 30 minutes after using a fluoride mouthwash.

Read more information about how to keep your teeth clean.


Try to avoid eating lots of food and drink high in fermented carbohydrates. This includes:

  • fizzy drinks
  • coffee and tea with sugar added
  • chocolate
  • sweets
  • cakes
  • crisps
  • biscuits
  • white bread

Healthier alternatives for snacks and drinks include:

  • cheese
  • fruit and vegetables
  • sugar-free gum
  • unsweetened tea, coffee

You should not avoid carbohydrates altogether, as they are an important part of a balanced diet. But try and choose the type of carbohydrates known as unrefined carbohydrates, as bacteria finds it harder to break these down into acid.

Good sources of unrefined carbohydrates include:

  • wholemeal or brown bread
  • pasta
  • rice
  • potatoes
  • leafy green vegetables
  • eggs

Read more information on lifestyle tips for healthy teeth.

Sugar and food labels

Check labels on foods to see how much sugar they contain. Sugar comes in many forms, so look out for the following ingredients:

  • glucose
  • sucrose
  • honey
  • dextrose
  • maltose
  • fructose
  • hydrolysed starch or syrup

Ingredients are usually listed in order of the amount used, with the main ingredient listed first. If sugar, or one of the ingredients above, is near the top of the ingredients list, it may mean the food is high in sugar.

Some products also use the traffic light system as part of their labelling to indicate whether they are high or low in sugar:

  • a red light indicates a high amount of sugar
  • an amber light indicates a medium amount of sugar
  • a green light indicates a low amount of sugar

In general:

  • high in sugar means more than 15g of sugar for every 100g of product
  • low in sugar means less than 5g of sugar for every 100g of product

Chewing sugar-free gum after you have eaten may also help prevent tooth decay. When you chew gum, your mouth produces saliva, which neutralises the acid in your mouth before it can damage your teeth.

Read more information about eating a healthy, balanced diet for healthier alternatives.

Page last reviewed: 07/06/2012

Next review due: 07/06/2014


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