So! I'll start then. I have a number of thoughts regarding this condition, so I guess I want to compare some things.

1. What exact tooth do you mean? Mine is upper left lateral incisor, #10.

2. When did your pain start at first? Before or after root canal?

For me, it was after deep filling, but before root canal. I had to do root canal because of this pain, but it never went away.

3. Your symptoms worsened over time, with every root canal, correct?

Mine sure did.

4. How would you describe the pain? What is it like?

Mine is throbbing / burning / drilling! / sometimes shooting. In the gum and somewhere around the tooth, mostly. May wander a little bit to the left or to the right.

5. Is the pain constant, every day? Or are there days when you almost forget about it?

6. Does the pain radiate anywhere?

Sometimes, but not often, I feel tickling in my nose, like the pain wanders there. It may also hurt under my eye, but this is not that often.

7. Do you have reaction to warm and/or cold?

I cannot eat even slightly warm food now. I can drink water of only neutral temperature, too hot or too warm triggers the pain.

When it all started, I could eat more temperature ranged food. It gets worse

8. Do you sometimes feel that your gum is on fire?

Because all this time I multiply felt like I have burned my gum with something too hot. It was one of the first symptoms.

9. Does brushing your teeth make things worse?

10. Have your ever triggered pain by applying something hot to your face?

Because for me not only hot shower triggered the pain, but sitting with my left cheek IN SUN ON A HOT DAY. Maybe it was a coincidence, but.. who knows.

Woosh, 10 questions will be fine for now, I guess. But I'm sure I will have more thoughts later. Waiting for your replies.