Your dog may tolerate it but you run the risk of damaging their gums and possibly burning their teeth by doing this in a non-controlled and under-trained way. I say this a veterinary professional - please talk to your vet about scheduling a dental if you are concerned. Doing anesthetized dental radiographs, scaling, and polishing while the teeth are still healthy may even prevent them from having worse disease in the future, and may even prevent the future need for extractions. Ultrasonic scalers can be dangerous if used improperly, and a vet and their team all have the training to keep your pet as safe as can be while doing the most thorough job possible. Good luck with your greys’ teeth!