Bit of an odd query but is there some kind of vitamin insufficiency that would cause a dogs teeth to break / crack?  A colleague has a Japanese Akita that has 3 broken teeth that he is blaming on a boarding kennels where he boarded his dogs for a week about 3 weeks ago (and has only just spotted the teeth??).  Other than chewing something hard, fighting with his other Akita etc would there by any kind of heath issue that could cause this tooth damage - I have told him that it's not fair to lay blame on the kennels when they may not want to inspect a Japanese Akita's teeth (esp when he told me the dogs were not too friendly towards the staff) and therefore may not have spotted the bad teeth, I am trying to give him alternatives such as the dog could have done this in the time that he has been back and not only when in the boarding kennels.  I too put my dogs in this kennels for 4 days and they were great, no probs at all and I did check them over when I collected them.

He could be right.  If his dog was trying to escape from the kennels by attempting to bite his way out then he may have snapped his teeth this way.  Some dogs can get extremely stressed in a kennel environment.