Ah....I've experienced it varies by geographic region. Ex. - when I live in Texas, I had my Shepherd of 13 1/2 years teeth cleaned, at the advice of the vet, once a year, starting at about age 3. He had bones, lots to chew, never ate soft foods (like cat food which gets stuck in gums and can impact gum and teeth health). I moved to Colorado, had a short stay on Illinois, with my sweet pup today, she's a 65 lb mix, now 4 years old. When I first got her at age 2 - the vets in Colorado looked at me like I was crazy for wanting to do a teeth cleaning, advised unless there was a problem, they wouldn't look to clean her teeth until age 5 or older, and even then it would not likely be annually - more of a "as needed". Moved to Chicago for a year....those vets had a similar message. Interesting learning for me....here is what else I can share....
First - ENZYMATIC doggie toothpaste. Please, spare yourself trying to go after your dog with a toothbrush out of the gates. You'll have a longer adjustment time but the ENZYMATIC kind (there are many out there that are NOT enzymatic) will at least have a positive benefit without using the toothbrush :-) So find one your dog likes, look at Amazons top seller. I started giving my dog a taste, no force. Just 2-3 times a week. She loves it. Next, when she's relaxed, laying down, we're watching TV (it's on the coffee table or nearby) I can place some on a finger and rub it on a few of her teeth. Of course 30 seconds in, she's done - she gets up - but hey! mission accomplished. No brush required. Next step, maybe next month, will be the finger toothbrush and that is where I will be happy that I've got her teeth cleaning under control. Per the vet, it can buy a couple of years before a formal cleaning under anesthesia.
Second - I discovered FIGO pet insurance. The annual premium is, or at least was less than $160 for the annual premium. Paid for itself within the first visit to the vet for an upset tummy. While it wont cover regular vaccines or annual exams, routine, I have found it a pocketbook saver. Shop around, but I think this is the best investment in covering health care for your furry family.