
To be honest if the teeth are fine as a baby puppy you take your chance that they will be fine when the adult ones come in.
If you say she still has baby teeth then the dentition is yet not certain, but it is always a risk that a pups mouth will go.
The only way of being sure to get a show dog, rather than a show prospect is to buy the finished article, which needless to say will not usually be for sale.
It is the reason most breeders will sell a puppy as promising/show prospect, but primarily as a companion first and foremost.
Even if the dog was perfection itself, it may not like showing, or an injury stop it from attaining it's promise. Same with breeding, you can't guarantee an animal will be fertile, a good mother/stud or a producer.