I've read a lot about how loss of back molars changes the face. Can this be true of wisdom teeth as well?

While it is true that tooth loss can affect facial structure, it's extremely unlikely that removing your wisdom teeth had any observable effect. Unless you're missing several other back to you, rest assured that you have not suffered any negative consequences as a result of your decision to have your wisdom teeth removed.

You will not have any appreciative negative consequences of having your wisdom teeth removed. Most of us do not have room for them anyway.Dental implants would not be an option because there is no reason to do them, there likely is no room for them, and they could encroach on the nerve that runs thru the jawbone back there.