u/boyferal

Hi everyone,
I noticed this white spot behind my last lower molar today (photo attached). The surrounding gum looks red and irritated. I’m not sure if it’s a canker sore, food stuck under the gum, pus from an infection, or something else.
I don’t know if it’s related to my wisdom tooth, but it’s located just behind my last molar. It’s a little sore, but not extremely painful.
Does this look like something that can be monitored at home, or should I see a dentist as soon as possible? Any idea what it might be?

Does anyone have a PDF copy of the book? I tried to buy it, but it’s out of stock in my country (I’m not from the US) i've been dying to read this book for years now but it’s almost impossible to find a copy :(