Have you had similar sores in the past? If so, have you noticed if anything in particular seemed to trigger them? If you have several canker sores, your doctor may prescribe a mouth rinse containing the steroid dexamethasone (dek-suh-METH-uh-sown) to reduce pain and inflammation or lidocaine to reduce pain. Topical products

Leukoplakia. This condition causes white or gray patches inside your mouth. It develops because of excess cell growth. Chronic irritation from things like smoking or chewing tobacco can cause it. But sometimes it happens for no apparent reason. Leukoplakia lesions usually aren’t cancerous. Make sure your child is drinking enough fluids like water and milk. Try offering them cold drinks through a straw if their mouth is very sore. Silver nitrate — another option for chemical cautery of canker sores — hasn't been shown to speed healing, but it may help relieve canker sore pain.Children, Women, and people with a family history are most prone to building up mouth ulcer. Following are the causes of mouth ulcers:

You can take up to four tablets a day, ideally leaving three to four hours between each dose. You can take them for up to five days at a time. Whilst they’re very effective, the fact that they contain a mild steroid means not everyone will be happy to take. Prescriptions must be written on an Authority Prescription Form, and the approval number must be noted on the prescription. Pharmacists cannot dispense the item as a pharmaceutical benefit unless it has been approved by Medicare Australia (indicated by the presence of the approval number). a long-term condition – such as inflammatory bowel disease (IBD), coeliac disease or Behçet's disease

We asked Susie Lloyd, dentist at Holt Dental Care and part of Bupa Dental care about the causes of mouth ulcers. “Mouth ulcers can usually be treated at home and should heal after 7-10 days. There are many reasons that we develop ulcers – some of which are predictable, some poorly understood. The cause of ulceration can be traumatic (wear from poorly fitting prosthesis – such as dentures, or an over-erupting wisdom tooth rubbing on the mucosa), infectious (herpes simplex virus, for example), drug induced (some drugs cause ulceration within the mouth as a side-effect or due to an interaction with other drugs you’ve been prescribed), due to systemic disease (erosive lichen planus or pemphigoid, for example), or as a result of malignancy or recurrent aphthous ulcers.