Does she enjoy the taste of the paste at all? Douglas' reward for it is he can lick the brush at the end. I hold him gently and pull his lip up with one hand and brush with the other. Be generous with the paste- it's safe for dogs, and it makes them more cooperative.
Our toothpaste was from the vet, it's chicken flavor.
I brush once in the morning with a chicken flavored toothpaste. At night, I put Petzlife gel on her teeth without brushing. The reason I use a regular toothpaste for brushing is because she tolerates its much more.
I also give her an edible chew twice a week. My girl is 7 years old with near perfect teeth now and I actually started brushing way later than I should have!
After poor little Prince man develop some issues with his teeth, I began brushing the whole crews teeth. They tolerate it suprsingly well. I started with a finger brush, then just let them chew on a pet sized toothbrush with some doggie toothpaste on it. I actually use a toddler toothbrush which is pet sized in my opinion. Like anything, keep it fun and if they resist, repeat tomorrow. I brush once a day. I use vanilla mint toothpaste for dogs (CET is the brand, available on Amazon). I also use an all natural dental spray by Healthy Clean Pet (also from Amazon). In fact, I need to start at least using the spray on Jewel to get her used to the idea. I think a good way to see if your dog will accept brushing is attempt to lift their lips, open their mouth and rub their teeth/gums with your fingers. The easier this is, the more they are likely to readily accept brushing. If this is not easy, I'd get them used to this before trying to brush.
I use petz life gel and the spray. I can use a baby tooth brush for Mojo and Mimi but with Leo, I use gauze on my finger. Lola doesn't let me brush her teeth but she does get dentals every 6 to 12 months.
Mia seems to like the taste..it's vanilla mint. I find that if I run hot water on the toothbrush and get the bristles really soft, she tolerates it better. I tried to use a finger brush but it's just too big.
She does sit and wait while I get it ready so at least she's not running away.
And if it's late like for Photobuff- you can always start right after a dental. I rescued Douglas with bad teeth and despite my efforts I could never get them under control. I feared putting him under but finally had to in order to have a tooth removed- so they did a full dental then. Since the dental keeping his tartar under control has been much easier and he will be less likely to need another dental later in life because I upkeep his little chompers.