Here's an interesting article from the AKC corner with video.  How simple you can make it, to brush your dogs teeth.   

https://youtu.be/F6S50BZU1D0

Here's my added 2 cents worth:  Find a toothpaste that they like, and it improves the whole process.  Poultry Flavor is thebest for my household! Just Saying!  KT