I have a pit of unknown age (guessed to be around 2-3 years old), and she does not have any odor to her breath. Well, that is unless she just ate something stinky like salmon or tripe. But, she does NOT have a permanent odor on her breath. All her teeth are a bright white with zero plaque build-up.
How old is your dog? If it is a really young dog (1-4 years of age), then you may have a broken/infected tooth or a mouth disease of some sort.
The best thing you can do for your dog is brush his teeth every day. I know that is a chore, but that is part of owning a dog. Things aren’t always easy and quick. Taking 5-10 minutes out of your day to protect the mouth of your dog is worth it, unless you want to spend thousands of dollars on tooth removal, professional tooth cleanings (which involves anesthesia), blood work, blood diseases, and heart conditions due to gum disease.
Gum disease in dogs (and humans) tends to lead to all kinds of trouble with the heart and the rest of the body. By not taking care of your dog’s mouth early on, you are shortening your dog’s life and looking to drain your bank account.
Just putting a treatment in the water dish isn’t enough. You need to do much more than that. Look at the teeth (canines through molars). Are they any color other than white? If so, you have plaque and possibly rotten teeth. A dog with a healthy mouth should rarely ever smell. It will smell temporaroly due to something he may have just eaten or licked. If it smells all the time, you have a serious issue at hand.
Look at the gums. What color are they? That is a sign of gum disease.
Get your dog to the vet and have his mouth looked at! Do both you and your dog a favor by taking care of his mouth.