I see VERY good results with the T/D prescription food. I just recommend using them as a treat a few times a day. My mother has a shihtzu who is 9 years old and has a history of bad teeth. We would get his teeth cleaned every year and he would still loose a tooth or 2 each year. So we started to use the vet recommended T/D as a treat and he hasn't had a dental in 2 years and his teeth are doing GREAT! Some of the smaller dogs with the flat or semi flat muzzles get teeth issues more then other breeds. My dogs are all larger dogs ranging from 2 yrs - 5 yrs and they chew ALOT and what works the best for their teeth are beef bones / knuckle bones. I think the crunchy style of the bone is what really cleans the teeth rather then the chewing type of bones. They all have beautiful teeth. =-) I am a firm believer in having the vet clean my dogs teeth when they get to a certain point which is not always at the same time for every dog. I have seen 4 year old dogs with teeth so bad it could have been the teeth of a 15 yr old dog. then we have seen 15 yr old dogs with beautiful pearly whites. It falls on the breed of dog and their habits of chewing and diet.