However, I just had a tooth removed and was talking to this new Oral Surgeon. He thinks it might be a Galvanic Reaction to all the metals in my mouth from crowns, gold bridges, and fillings. He says it actually causes a small electrical current that keeps the mouth irritated. He says he usually sees it in women, and has also to do with other elements in the body like potassium, zinc, calicum.
Makes sense to me since this has really started since having the additional crown and some new fillings. Its not an allergic reaction to the metals, just the fact that there is so much in the mouth and the body chemistry. I do have some food allergies, like strawberries, almonds, walnuts, oats and when I eat these, my mouth does get worse. However, the allergy doctor says most allergic reactions to foods are stomach issues like indigestion, gas, etc. although I do know my mouth is tender all the time and these things do make it sore.

If it continues go see your dentist or an ENT. They can give you a prescription for a rinse called Miles Solution. It contains an antifungal, a little steroid, an antihistamine. It helps too but if its like mine, which comes and goes all over my mouth, nothing cures it. There are other reasons for sores, like infections stemming from other things so maybe you should see a doctor. Have you been to a dentist recently for dental work or do you need dental care that has not been done?

I never did figure out the cause, but I don't think I have had an issue since. It could be chocolate, but not Cadbury. I don't think I've ever had that brand.

Now that I am reminded of this, I'll ask my dentist when I go next month.

After eating chocolate it is much more apparent (Not specifically Cadbury but any chocolate). I also get it after McDonalds Milk Shakes - which makes me think it's something to do with high Sugar foods perhaps in certain peeps, maybe not all cases reading here.

More specifically the spot is always in the same place, only 1 spot and it sometimes disappears completely for weeks.