Mouth ulcers are very common and often affect teenagers. They can be sore but usually only last about a week. They are normally up to 8mm in size – if you get ulcers bigger than this, go to see your dentist right away. Sometimes ulcers are a sign of a lack of vitamins or shortage of iron/zinc or even anaemia. A broken/sharp tooth or being a bit clumsy with your toothbrush can cause them. They can even be brought on by stress, or by being run down.
To help prevent ulcers, it important you eat healthily - 5 portions of fruit or vegetables is the recommended amount. Also, if you keep getting ulcers, take a multivitamin with iron and zinc. Avoid acidic foods as they will sting.

There isn’t really much you can do to make an ulcer go away more quickly, but you can use an antiseptic gel or an analgesic gel to make them less uncomfortable.

An ulcer should have gone in 2 weeks – if it hasn’t you must go to see your dentist.