Much of the dental industry literature is based on the original aluminium industry funded researched performed by the infamous Kettering Labs.

Here is a table of results from the 2012 Malmo study

The note the absence of water fluoridation in the majority of the top 10 countries.

By the way, when we are talking about the addition of Fluoride to the water supply, it isn't pharmaceutical grade product, but an industrial process byproduct that would normally attract a large disposal fee.

Now if you wished to argue the benefits in using dental care products containing sodium fluoride as a topical treatment, that may be a different matter (although stannous or calcium fluoride are likely more effective and thus utilized in the more expensive toothpastes). However, after you have brushed your teeth do you swallow the toothpaste, or spit it out ? If ingestion of sodium fluoride is a bad idea then, why add it to the water supply ?