Yes, parasites and acid cause tooth grinding in the sleep.
Hubby will do well on your raw diet plan.
De-worm,de-stone, do a 21 day fast and then maintaine a raw diet and he may live long past 100 or at least healthy till the day he dies peacefully in his sleep.
I have my Longevity kit that is my pet prodject for many years, won't know if it works until the 300 years study is complete!!!