I don't know the Lhaso standard without looking it up, but the Shih Tzu standard allows for undershot bites as long as the teeth do not show. I don't think you could even find a Shih Tzu with a scissors bite or if it would be correct.

Breed standard

Mouth
Upper incisors close just inside lower i.e. reverse scissor bite. Incisors in a broad and as straight a line as possible. Full dentition desirable.

My late, beloved Snorri-dog's lower jaw was undershot by at least 1/2 inch (Border Collie). It caused him no problems whatsoever, but, on his first visit to the vet (a few days after we got him), we were advised not to breed from him, for fear of passing it on. He even went into local shows, once coming second (admittedly, out of two!).Undershot jaw or not, he made a bl@@dy fine pet! RIP


Snorri

Puppies upper & lower jaws do not always grow in unison. If her bite was right at 6 & 8 weeks it should come right at the end. Have had shepherd puppies who have been both under & over shot at different times during their puppyhood but found if they were alright at 8 weeks they came right when they finished growing. Just enjoy her for now.

....... - look at any country with feral dog populations and they almost all conform to the same type - medium sized, prick ears, curly tail and wary temperament ( Think Canaan dogs or Basenji type) ...are you saying that anything that does'nt fit this 'blueprint' is 'deformed' - what utter nonsense !!

I tell you if this is what young vets are being told at Uni then god help us !!

Elaine V W

I have a seven year old Lhasa - he is absolutely beautiful and 3 days ago I got another, a lovely little 9 week old boy. Yesterday I took him for his first shot and the vet informed me that he would have an undershot jaw, which I felt very upset about. He doesn't even have any front teeth yet! I have no plans to breed from him but it's not nice to be told that your puppy is defective in some way. It was heartening to find that some people felt that his jaw structure was still forming and could change.

Lhasa's should have a reverse scissor bite. That is the top teeth are just behind the bottom ones. An undershot jaw (the correct term) is visible at birth if its bad enough, puppies dont need teeth for it to be seen.

Your puppy at 9 weeks should absolutely have front teeth and to be honest Id worry more about that than a possible undershot jaw.

Agree with the above , I would also be worried that my 9 week old pup had not front teeth.

What was the breeders explanation for this ?

The lower jaw is always the last thing to develop anyway, so you will need to be looking again at it when they are around 18 months.
No teeth at 9 weeks - deffo a more worrying thing and I would have been asking the breeder questions about that before paying any money over and collecting the pup!!!