my dog, boxer has bad breath?

If a dog has particularly bad breath then you need to look for reasons.

It can be internal disorders and some of them serious. It can also be gum disease or it can be just the food you are feeding.

Whatever way a dogs breath shouldn't just smell. It is ok using all the dentastix etc but if there is a problem then you need to know about it.

Have his anal glands checked to see if they need excreting.
This can cause bad breath as they lick their rear end a lot as its uncomfortable.
A vet or groomer can do this easily.

Brush his teeth and daily dentastix (the fresh kind, they are green, made by pedigree) ... also, the vet can do a dental cleaning. And of course, rawhides and nylabones! We do all of these things, minus the dental cleanings, our pup has pretty white teeth and fresh breath! Good luck!

Give him a bone or at Pet smart has a breathe spray.

Don't brush his teeth! It will make his breath smell worse!
What works for my dog is having him drink a lot of water. It cleanses his mouth.