M.O.
Hi C.,
When my 4 year old had her tonsils out she had the same problem... doctor told me it was because of the healing/scarring in her throat and she just needed time. It was so bad you could smell it when you walked into the room she was in! Poor thing, but it did pass after a few days and as she began to eat more frequently and more solids. Brushing alone did not help her either. Hang in there, call the Dr. if you are concerned, but it should get better soon. Good luck, hope he's feeling better soon!
M.