Okay, they chew with them, bite and chew on toys and chew items that are supposed to clean and take tartar off so do we have to clean them?
You should but life gets in the way of many of us so bones, things like a spray of Leba II etc will help and in some cases do the job.
Otherwise, when they have a good case of tartar, you ought to get them cleaned so they don't lose their teeth.
We use the Leba and a finger thing that we get from K9groomingsupplies and every now and then we have to get a teeth cleaning but it has reduced the times necessary.
I should be brushing each time I groom. But not all dawgs enjoy your fingers all over their teeth.
What do you do for YOUR dogs?