About 6 months ago, I developed what appeared to be a blister or sore on the roof of my mouth. It stuck around for a week or two and finally went away. Now the thing is back, and has been stubbornly sticking around for weeks. It gets irritated depending on what I eat, and varies in size.

It looks like a big pimple, red with a whitish/yellowish center. I looked up "mucocele" but it seems to be smaller than that. My dentist didn't say anything about it, so I assume it isn't serious (I'm 34 and don't smoke) -but it is annoying!

Could this be a canker sore? A cold sore? can they stick around this long?

Go to the doc and double check just to make sure it's nothing serious. Our family has had breast cancer, luekemia, and mouth cancer pop up in the last 5 years. Always better to be safe then sorry.
Sorry I can't help any more:) Theres lots of great people on the board maybe they can chime in:)

chatty

Unlikely to be a canker sore--these are usually ulcers found on non-attached tissue to bone (such as lining of lips, cheeks ect)

It could be a variety of things, hard to say without seeing it or knowing more about s/s and duration. It could be benign (cyst). However, there are cancers that affect the palate also. Therefore, it would be in your best interest to seek professional advice when the condition appear. An oral surgeon or ENT are your best bet since your dentist would refer you anyway.