Should I be worried?

Cats don't lose teeth because of cat fights. They lose them because of infections. The most common are periodontal diseases such as gingivitis. These can be very painful, which is probably why your cat was snarling like that.

He really needs to see a vet as soon as possible. The vet will be able to clean his teeth, treat his infection and give you some advise on the best diet for him.

You probably know yourself how painful toothache can be so please don't wait. He should get this seen to right away.

Cats pawing at their face always worries me - it means something is bothering them so much that they need to physically reach out and do something about it, and often times, especially when it involves their mouths, it's quite painful. Changes in behaviour can be a result of pain as well, so the unexpected trigger that made him crazy just as he was dozing off could have been a spike of pain. Even perfectly healthy people have bad bouts at some point or another - you can't be in perfect health forever. Best to be proactive and get it treated sooner as opposed to later, when it's not only more painful and severe, but expensive too.

Please have him seen by a vet ASAP.

Take your cat to a vet.  If he/she is loosing teeth there is something wrong.  Have him tested for FIV.

Thanks guys! But, when he goes to the vet, other then being so aggressive they have to knock him out, he always comes back healthy. (Seriously, this cat would eat a baby if he could.) And, like I said before, this has been going on for a couple years and the vets always say he's fine and not to worry, 'He's just getting old/knocked around by younger cats' and has never been sick.

I suppose I should tell you guys a bit about him, right?

He was rescued from a hoarding/breeding spot as a very young kitten. However, almost never having human contact caused him to become feral. He was infested with fleas so badly that he had more fleas than fur. Up until he was (what we guess to be) 8, he openly attacked anybody who came near him. Its only now that he's losing teeth that I can comfortably be near him. Which, paid off because he now sleeps with me each night and purrs. I still cannot pick him up or snuggle him. But he likes a good scratch behind the ears once in a while. And, looking at him now (asleep in my sweater) you wouldn't know he was as mean as he is.  Funny how that works, right?

I've got a mean old tom cat as well. That's him in my avatar. He's actually nowhere near as mean as he looks, he'll let me pick him up and hug him and since I got him neutered a few years ago he never fights with the other cats. But he had a rough life on the streets before I picked him up.

If you look closely you'll see that his mouth is lopsided. That's because he had to have most of his teeth removed. He had an oral tumour around one tooth when we first found him, then lost two more teeth to gum disease. Cats don't lose teeth because of fighting. Think about it, it's not like they punch each other in the jaw, right? Cat fights are more likely to result in scratches, puncture wounds and infections. If his teeth are falling out it's because he has something wrong with them.

Is there another vet near by that you could get a second opinion from? Pawing at his mouth and snarling the way you described really sounds like he is suffering. When I have to take my wilder cats to the vet I get one of those big laundry nets, put them inside and zip it closed before I put them in the carrier. It makes it easier to get them out of the carrier when you get to the vets and easier for the vet to examine them.

It sounds like your cat had a rough start in life, the same as my Gin kun. That could be why he's having problems with his teeth now.

Have you ever had a toothache -  "crazed with pain" is a saying for a reason and a toothache can definitely get you there. 

You clearly have a soft spot for the cat (even though your avatar says dog person!) and he loves you.   I agree with the other posters that you need to take a shot at a different vet.  He definitely needs someone in his corner  to get to the bottom of this.  Keep us posted OK!

I have two vets, one who treats my indoor cats and one the treats my semi-feral cats.  When they are in the carrier they are scary.  They wear leather gloves and reach right in and scruff them with no fear.   The vets I use for my indoor cats would have no idea how to handle the other ones. Maybe a vet used to handling the more feral animals can do a proper exam on him.

Wow! So much input! (Seriously. Thanks!)

Okay, first off, there are NO OTHER VETS in my area. And I CANNOT afford the gas to go driving around to another vet. (Over $100.) And, before you all ask, he's fixed and he GOT WORSE after. Seriously, if cats never sprayed, I would have just let him remain intact. Also, he very well could be losing teeth from getting smacked around; he's gotten a few smacks from people he's attacked. And...I have seen him fly into mirrors...a lot. (Not the brightest bulb in the box.) And, like I said, the vets all say he's fine. (When I got him, there were two vets.) The first one closed out shortly after they saw him about his teeth. They said he was fine and transferred his papers to the one we go to now and they re-examined him and said he was fine. After they pulled his teeth/claws from their faces. Scruffing doesn't work. Nothing works. If he wants to bite you, he bites you. I have scars from where he's dig his teeth right in.

And yes...I have a soft spot for him. Up until he came around, I liked KITTENS. And ONLY kittens. (HATED cats.) I actually spent most these years begging somebody to just take him. No questions asked. Couldn't stand him. (Or well, his behavior.) But...when there was a fire (a nearby fire pit wasn't put out right and something from that got on my roof. Thankfully, only a small part of the roof burned and nothing else.) and we (my family, the dogs and I) were all out, I realized he wasn't with us. Everybody said he was probably in under the bed or had gotten out and was hiding under a car but I was worried. Smoke inhalation is HELL. And, if the fire department uses their oxygen on an animal, they get arrested. So, I really was worried he was gone. A few days later, though, he was found a couple houses down under their house. We might not have gotten along or liked each other. But, that proved we loved each other.

So, over 10 years in, I have saved and collected/rehomed a lot of cats. Though, the only ones with a worse temper or who are larger than Mr. Fuzzy Feral  are wild cats. Looks like a mini cougar and sounds like one, too. Right now, he's asleep. Has been all day. Like everyday, he's asleep and then up all night. Like me.

Oh, and something I forgot to mention...no rescues here will take ferals; they'll put them down. They say you CANNOT tame them. (I proved them wrong. Kinda. He's still a savage but...he's also a top-notch snuggle buddy. When he wants to be.)