Canker sores are bacterial, non-contagious infections that occur on the gums, inner lips, inside the cheeks and sometimes on the tongue. They are usually red and round with a white center. Most canker ...

Canker sores often seem to pop up out of nowhere and, once you have them, they’re often painfully hard to ignore — especially when you try to eat or even talk. So what, exactly, are canker sores? They ...

Have you ever woken up to find an annoying red or white bump inside your mouth or on your tongue? It might just be a canker sore, also known as an apthous ulcer. Here's more information about why and ...