I have to agree with Aphistis. But... I have seen this controversy in dentistry from a personal perspective because of my background in dental hygiene. This issue is as touchy as religion to those who don't believe in fluoride and amalgam. These patients will act like you are poisoning them by even suggesting they need it (this has been my 6 years of previous experience and working for a dentist who had a large naturopathic patient base). There has been research in dentistry to support the recommendation of fluoride on adults because of recession related root caries (cementum is not as calcified as enamel), drug induced xerostomia, autoimmune malfunctions of the salivary glands/or cancer, and other issues that cause an increase in caries in adults that warrant the use of topical fluoride on them. Boy let me tell you that it is a challenging conversation to explain to patients who look horrified at this recommendation that systemic is not the same as topical, but I digress....
My point is that they don't (the patients) have the level of understanding and critical thinking usually to dissect all this misinformation and false research that is out there. Some do as they are the N.D.s and other health practitioner that have bought into this philosophy. As health practitioners it is our job to help them, but keep in mind this is a very, very touchy issue with those that bring up their aversions to it.
This issue will not go away, and is something that depending on where you practice you may become more or less embroiled in. Personally, like I said earlier agree with the ADA on the use of fluoride and amalgam. I am just shedding some light on my experience in a "naturopathic" like practice and what I saw while working there.