Is turmeric and coconut oil good for teeth?

I never heard of such a thing. We know that islanders in most parts of the world and forest tribes in some parts of the world have perfect teeth. If you compare their diets to yours you will find the differences, mostly a matter of minerals in the water and lack of refined foods. They certainly do not get turmeric and coconut oil. Those foods don't even grow in the same places.

You need to study some books about nutrition and stop asking strangers for guidance.