In an advance toward solving a 50-year-old mystery, scientists are reporting new evidence on how the fluoride in drinking water, toothpastes, mouth rinses and other oral care products prevents tooth decay.
Karin Jacobs and colleagues explain that despite a half-century of scientific research, controversy still exists over exactly how fluoride compounds reduce the risk of tooth decay. That research established long ago that fluoride helps to harden the enamel coating that protects teeth from the acid produced by decay-causing bacteria. Newer studies already found that fluoride penetrates into and hardens a much thinner layer of enamel than previously believed, lending credence to other theories about how fluoride works.
The report describes new evidence that fluoride also works by impacting the adhesion force of bacteria that stick to the teeth and produce the acid that causes cavities. The experiments – performed on artificial teeth (hydroxyapatite pellets – the primary component of tooth enamel) to enable high-precision analysis techniques – revealed that fluoride reduces the ability of decay-causing bacteria to stick, so that also on teeth, it is easier to wash away the bacteria by saliva, brushing and other activity.
We routinely recommend fluoride treatments after routine dental cleanings, as thew teeth are the absolute cleanest then and the fluoride can integrate with the enamel most readily, and for those with decay and tooth sensitivity issues, we recommend nightly home fluoride treatments with prescription-strength fluorides only available from pharmacies or dental offices, by prescription.
There have been some questions raised recently about hypothyroidism (low thyroid hormone) and fluoride use, despite fluoride being in the water, naturally-occuring in the water, and a part of toothpastes for more than 50 years. At this point, there is no scientifically validated evidence that this is true, although we will keep you posted. If there are problems, it certainly has not been an epidemic, and we doubt that in the long run much evidence will be there to support not using fluorides because of potential thyroid problems. It is more likely that thyroid problems have developed due to a variety of other causes, mostly environmental or autoimmune.
For now, fluoride is the best option available, and until something better is available, we wholeheartedly recommend its use.