IV sedation for dentisty and diabeties

Might be worth checking with the dentist whether he/she gave you a longer-acting painkiller in the mix or an injection. After I had my shoulder manipulated under general anesthetic, the surgeon gave me an injection in the shoulder to take away pain in the following days (I think it was cortisone, but it's been a while!)
Upshot of it was that the painkiller had the side effect of raising the blood glucose too. If you search the forum here, you'll probably find references to cortisone having that effect.