Back in the day we fed canned, but most of their food was off our plates, scraps, our one Mutt loved his bones.
When we started buying "popular" kibble in the '90s, all heck broke loose so just kept trudging them to Vets. Two dogs who were born in or prior to the early '80s wouldn't eat it, so we had to keep getting the canned and loading it with enough people-food for them to eat it. Funny how they lived so long, while the younger dogs suffered greatly. We thought it was just bad luck --and two dogs within two families died before their time from "bloody intestinal growths" in the mid-2000s; different households, ate the same brand. (We had 6; sister had 2, always finding strays...)
Other "mysteries" consisted of bloody hot-spots on paws and legs (wouldn't stop chewing despite all the Meds); another was going bald with them, and had chronic ear infections.
I know now it wasn't just "coincidence" the senior dogs living with them didn't have these issues, or ever needed "teeth cleanings".
That's our experience. How we got so far away from the basics, I'll never know. But having so many dogs certainly made buying those bags seem like an economically sound move!
You mention google so here is a favorite bookmark
http://www.rawfed.com/myths/kibble.html
and more insight here
http://www.cnpca.org/2011/01/14/anesthesia-free-teeth-cleaning-for-dogs-and-cats/