question: Hi i recently developed a canker soar in my left cheek back where my wisdom tooth is growing in. thought it was fine until i used my tongue to feel around it one morning and it had a boxy lump around it and it comes out all the way to my gums and it hurts to touch it open my mouth or spit and eat. What could it be and how should i treat it? The soar is white and it caves in a little.