Hi Deb,
Thanks for your question.
Any time you notice a change in your pet, it is always a good idea to have it checked out by your veterinarian. A crusty nose could be a sign of a respiratory tract infection, which is a very common problem we see in cats. Feline herpesvirus, calicivirus, chlamydophila, and mycoplasma are some of the common infectious culprits. Your vet can perform tests to determine if any of these are present and select an appropriate treatment course. Other things to consider would include nasal foreign bodies, airborne irritants, allergic disease, growths or tumours and of course, dental disease. Cats are very good at hiding illness and discomfort. Although your cat may seem to be acting normally, it is best to have things looked at by your vet.
Wishing you all the best!
Dr. Kim Hester