Dental decay happens when the enamel and dentine of a tooth become softened by acid attack after you have eaten or drunk anything containing sugars. Over time, the acid makes a cavity (hole) in the tooth. ‘Dental decay' is the same as tooth decay and is also known as ‘dental caries'.
Dental decay is caused by plaque acids that gradually dissolve away the enamel and dentine of the tooth. Decay damages your teeth and may lead to the tooth needing to be filled or even taken out.
Decay happens when sugars in food and drinks react with the bacteria in plaque, forming acids. Every time you eat or drink anything containing sugars, these acids attack the teeth and start to soften and dissolve the enamel. The attacks can last for an hour after eating or drinking, before the natural salts in your saliva cause the enamel to ‘remineralise' and harden again. It's not just sugars that are harmful: other types of carbohydrate foods and drinks react with plaque and form acids. (These are the ‘fermentable' carbohydrates: for example ‘hidden sugars' in processed food, natural sugars like those in fruit, and cooked starches.) Always check the ingredients. Generally anything with ‘ose' in the name is a sugar, for example: sucrose, maltose and so on.
Having sugary or acidic snacks and drinks between meals can increase the risk of decay, because your teeth come under constant attack and do not have time to recover. It is therefore important not to keep having sugary snacks or sipping sugary drinks throughout the day.
Toothache is a sign that you should visit your dental team straight away, as it is a warning that something is wrong. If you don't do anything, this will usually make matters worse and you may lose a tooth that could otherwise have been saved.
If the decay is not too serious, the dental team will remove all the decay and repair the tooth with a filling. Sometimes the nerve in the middle of the tooth can be damaged. If so, the dentist will need to carry out root canal treatment by removing the nerve and then repairing the tooth with a filling or a crown. If the tooth is so badly decayed that it cannot be repaired, the dentist may have to take the tooth out.
The best way to prevent dental decay is by brushing your teeth thoroughly last thing at night and at least one other time during the day, with a fluoride toothpaste. Make sure that you brush the inner, outer and biting surfaces of your teeth. Using ‘interdental' brushes, or dental floss or tape, also helps to remove plaque and food from between your teeth and where they meet the gums. These are areas an ordinary toothbrush can't reach.