Ask a Dog Vet and Get Answers to Your Dog Veterinary Questions
I am sorry that you have been waiting for a response. I recently just logged onto the site and noted that your question hasn't yet been answered. I am a licensed veterinarian with over 25 years’ experience and would be happy to work with you if you are still needing assistance.
You are absolutely correct that the area is filled in by cartilage and when you palpate any dog's skull, it will feel like the ocular orbit is intact.
I do not have an explanation for you as to why it is open. It serves no purpose and you have to go back very far in history to find any hint of a more fully closed orbit. It may have to do with the evolution of dogs as a species.
I hope this is helpful. Please let me know if you have ANY other questions. My goal is to give you 100% satisfaction and if you are not yet satisfied, please reply so I can clarify for you.
My posted replies are for general education only and not meant as a diagnosis. Only after a thorough veterinary examination can a diagnosis for your pet be made and specific treatments be advised or medications be prescribed.