I wouldn't expect a dental to
prevent future issues. Dentals just "correct" existing issues, and in the case of cleaning, possibly delay future issues. But IMO, they don't prevent them from happening. A species-appropriate diet, IMO, does. The body can and wants to heal itself. It just needs the right tools (nutrients) to do that.
You went all-raw with them. Because of that, they are now getting a super-healthy diet that's providing them the nutrients they need to maintain their health, including dental health. I truly think dental health is just as much (or more) about the proper vitamins and minerals than about "cleaning" the teeth with bones. I'm sure chewing on bones helps, but I personally think it's more about the nutrients IN the bones that makes the difference.
The furkids are getting what they need now. So I think, barring anything catastrophic, that it's very possible they won't have dental issues in the future, or if they do, that they'll be minimal, as long as they continue on raw.
Just my
.