My family has never used fluoride or the other additive you mentioned. Our water source doesn't have it (luckily) and we avoid it in our toothpastes.

We are a fairly typical American family otherwise, so we don't have the best diet, though we do avoid some of the more egregious sugar-based items like sodas, etc. We certainly eat too many carbs.

Anyway, we don't have tooth problems. This is purely anecdotal of course.

On a side note, many of my sons friends do have tooth decay issues despite using fluoride toothpastes. The dentists in my area even recommend fluoride pills for those of us within the fluoride free water district. We don't take it, but many do.

I'm not saying that fluoride doesn't work. But I am pretty skeptical based on my experience.