Hardly anyone is talking about this but there has been research for years of how nutrients like minerals can heal cavities. External treatments can be helpful at the same time. But to get the root causes involves nutrition. Your teeth reflect your nutrition as a whole which depends on your individual deficiencies and excesses.
A "take this for that" strategy the limited allopathic approach: narrowly focused treatement of the symptom from the outside. While this can be worth the effort for teeth, other health problems will likely reman and teeth and gum problems may reappear, since teeth are the tip of the iceberg of bones and the body as Weston A. Price explaiend.
You need to identify all nutrient deficiencies of minerals, vitamins, protein, fat, sunlight, probiotics, etc. And test for excesses of foods like carbs or maybe meat in some cases, and food allergies so those can be corrected.
Teeth are constructed from mainly calcium AND phosphorous, but calcium is often not lacking but simply not utilized due to magnesium deficiency, which depends on sodium and potassium. Teeth and bones also depend on boron, silica, vitamin A and D, which depend on a lot of fat...and more. So it's all related as a whole system. If you approach your teeth this way they the tip of the iceberg of your bones and your whole health so you can address all health problems at once.