Cleaning Stained Teeth

Hi

I have a 14 month old female Bull Terrier named Maggie. She was given antibiotics as a pup and they stained her teeth brown. Her teeth look like she is 14 years old not 14 months.

Is there any reliable way of removing the stains. I spoke to my vet who of course had no answer. Its only a cosmetic problem, the vet said there is nothing physically wrong with the teeth.

Cheers