as far as i know there are no K-9 in the justice department. but i remember a comic with an "bloodhound robodog" (with the size of a vehicle...dredd rode on it on a pursuit of a perp via scent of the "dog")
i think i don't understand your "dentist question"
there is no special "DEA" or something like that. so "sugar crimes" will be fought by "normal" Judges (perhaps some undercover wally judges).
i think dentists are just normal dentists

but if a dentist thinks his patient is a regular sugar consumer and DON'T alarm the Justice Department, he is part of the crime.