I'm about to write a character who get painful cavities.
- How would the first pain be?
- When would they become impossible to ignore?
- What do they feel like?
I'm not looking for something requiring root canal, but it should be painful enough that eating is a bother. I'm also looking for colorful metaphors. This is someone that would be only vaguely aware that people can and do get cavities, and never brushed his teeth (although the character is not actually human).