Hello, I'm new here. Read a post about overshot jaw. My English Mastiff pup had a perfect scissor bite at 8 wks. Now at 12 wks. his bite is slightly overshot. I have heard of slightly undershot jaws correcting with time, but I hope this will correct itself as he is one of the best Mastiff pups I've owned. Last guy was the best in a litter of Champions. This pup has a lot fewer Champions but is a very good pup in comparision.