A lot of people have their dogs' teeth cleaned annually under anesthesia. Obviously it is more expensive than regular dental care but aside from the risks to anesthesia, is very common.
Lady had a tooth pulled while she was already under during her spaying and I was told to just feed her soft food/treats for a couple days. I think they generally recover very quickly unless an infection develops. If anything Leo will just be sleepy from being put under.
Before I got Gracie (I took her home when she was 3 years old) she had annual teeth cleanings under anesthesia but I don't think I will continue this since I am trying to keep up with regular dental care at home. But with their tiny mouths I know it can be hard! On top of regular brushing I try to give lots of raw bones (~ 3 per week) and I also use a water supplement called Healthy Mouth.
Good luck to Leo
Lady (1.5 year old tricolour) & Gracie (4 year old blenheim)
"Happiness is a warm puppy" - Charles M. Schulz