There isn’t too much variation in how much a person will need to spend on those during their lifetime.
Presbyopia literally means “old eyes” and the risks of periodontal disease increases roughly linearly with age and closer to exponentially if your a long term nicotine user; to name but one example for each.
They eyes are also often the first place to (outside of specific blood tests that are not routinely run) see signs of diabetes, thyroid disease, and certain types of brain tumors. The mouth is the leading cause of sepsis. So both are important for people of all ages from a preventative medicine standpoint.