Hi Erik,
the back teeth are the grinders of the dentition: they need exercise. Gradually eliminating alcohol, sweets, and juices from your diet would assist this to occur as you would then be left eating real foods that require real chewing.
Other strategies include: heart & lung herbal tonics, aerobic exercise, chewing exercises (you can begin with the softest of the doggie toys in the pet shop or just clenching a rubber dummy for 20 minutes), yoga stretches for the lateral parts of the body, i.e, side bends and so forth.
The lower molars relate to the heart by the meridian system, and the upper molars to the brain. The second to last on the bottom row are the most decayed, per person, worldwide, and they relate to the lungs. Pranayama, bread or rice spiced with a lemon herb or a pepper herb will clean out the lungs over a couple of winters, enabling the body to strengthen this meridian to point of saving the teeth.
All these strategies work slowly, in a long term way. Each of them must go via the bone marrow before real gains are made and tooth weakness or tooth decay is halted. The bone marrow is the most sacred of the body's tissues, and responds more easily to long term strategies than radical efforts.
Once one of these lifestyle changes reaches the bone marrow (this occurs with the passing of day and night, winter and summer, etc.) then more of the necessary blood cells for tooth repair will be produced, called osteoblasts and odontoblasts, as the bone marrow controls the blood cell production.
Your dentist may tell you that this won't work. Further, even if it does work (and it will almost certainly work if you do it systematically and steadily), you may still need help from a dentist for a year or two until your body halts the damage to your teeth that is going on at present.
I have no dental fillings or other dental work in my body. My teeth are all natural. My website,
http://www.worldofteeth.com, explains my system, and it is there now, under the tab "ORAL HEALTH".
Kind thoughts,
Sebastian Reed