Hugs for the toothache, have had more than my fair share, so can sympathize.
Just bringing up one point, on the off chance it relates to you. Ive had 3 years of pain/infections in the ear/nose/throat/dental area. All which I would put down to a yeast infection. Obviously high BG and yeast can go hand in hand. The mouthwash Corsodyl works on both yeast and bacteria, so might help. But the main thing is BG control. I realise its about a 1 in 50 chance this applies to you, but said I would mention it, in case it applied to others.
The other thing I have done in the past is swirl with whiskey, with mixed results. But sometimes it deadens the nerve, and gives a few hours relief.
Best of luck at the dentist.