Now read this pages symptoms = Bad breath. Maybe not, but a starting place for sure.
It also can cause the sinuses to be congested all the time.
Maybe there's still an infection where the RC was removed.
If it were me, I would stay away from antibiotics and after irrigating the sinuses would put droppers full of colloidal silver in each nostril repeatedly because if it's infected from the tooth it could keep re infecting until you get that problem fixed.
Also I would not do the recommendation for acetaminophen as it has been linked to liver problems,etc.