Wheel Hub Dust Cap Damaged; Required?

I dented the piss out of one of my wheel hub dust caps replacing my wheel bearing the other day. I can't see what it keeps dust or dirt from but I guess some muddy water could get in behind it then work it's way past the splines then get into the wheel bearing, but that seems very highly unlikely. It's $19 to replace but I will if necessary.
Does this actually provide any protection or no need to replace it?

 

To me it seems like cheap insurance against early wheel bearing failure considering time/labor plus parts to replace the hub/bearing assembly. I can't say that those caps do a whole lot, but Toyota thought we needed them.

 

It will keep any water out that's for sure. I have a small dent in my drivers side and compared to my passenger side, I can see difference. I applied some rtv on the dent to keep the crap out.

 

I would replace it. I've popped off peoples virgin dust caps, and it looks brand new in there.

Mine has a big dent in it from me impatiently prying it off. A few months later I popped it off again and there's a light surface rust everywhere. I'd replace it if I were you.

 

The thing is you have not lived a full life until you have tried to remove a CV shaft that has rusted its splines inside the hub. I had to use a 10 lb. sledge to get a rusted CV out of a Subaru one time. It ruined the CV, wheel bearing, hub, and made the knuckle suspect too. Very expensive.

 

Well, that settles it. I'll order a new one! Thanks.