Aggressive behavior in female cat

Question
Hi Hilary:
Maybe you can help me, I'm at the end of my rope.
I have two cats, both 8 yrs old and they have always gotten along fine.
Last week, I had to take the boy cat in for a dental, and he had to have all his teeth removed - they were totally rotten. He's actually doing really well (bless his heart), but as soon as I brought him home from the vet's office, the girl cat went nuts. She's hissing and growling at him, and me sometimes too. My apartment has become a war zone and I've had it. It's gotten a bit better over the past couple of days, and I'm trying to soothe her and whatnot... but this isn't going away.
(She had a traumatic vet visit just last month)
Do you have any suggestions for me? I really need help with this or I'm afraid I'm really going to start smacking her around.
The advice I received from the vet's office was to pay more attention to her, and pet her and love her, etc... It's not helping.
(I also posted this question to another volunteer)
Thanks for listening - Wendy  

Answer
Hi Wendy!  I have 5 cats.  This happens everytime one of them goes to the vet. (all of them have been rescued and are skittish at one time or another)  I have been told and I have experienced, that when a cat comes home from the vet, they have the vet hospital's scent on them.  This panics the other cat(s) because they fear the vet.  This behavior usually wears off within a two week period.
What I have found to help, is spraying my cats with puppy cologne so they all smell the same.  I recommend this to alot of people, as it truly does have a good effect and takes away from the overpowering "vet scent."
I know how frustrating this behavior can be.  Keep patience...acting out on anger will only make it worse.  Hang in there...she hopefully will be over her temper tantrum soon!
I hope this helps and please keep me posted!
Hilary