As long as you get him used to your brushing his teeth - that is the main obstacle.
Barley used to queue up with the children when they were younger - she had their old brushes (Power Rangers/Glow in the dark Scooby Doo) and seemed to like the raspberry gel children's toothpaste. After we had brushed, we rinsed (by flushing the loo so she could have a drink ...)
Depending on their teeth, some dogs seem fine, whereas others definitely benefit from brushing - you can get those little finger things (like they used to use in the Bank for counting notes !!!) which aren't as invasive as a brush ...
Dentals cost the earth if you have to have a Vet do it, but it is better than having the dog suffer with toothache or have to have lots of teeth removed ...