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.
Research established long ago that fluoride helps harden the enamel coating that protects teeth from the acid produced by decay-causing bacteria. Recent studies confirmed that fluoride penetrates and hardens a much thinner layer of enamel than previously believed, lending credence to other theories about how fluoride works.
This latest report describes new evidence that fluoride also works by reducing the adhesion force of bacteria that stick to the teeth and produce the acid that causes cavities. Researchers tested the adhesion of Streptococcus mutans, Streptococcus oralis and Staphylococcus carnosus on a toothlike surface (smooth, high-density hydroxyapatite pellets) to enable high-precision analysis techniques.
The findings revealed that fluoride reduces the ability of the decay-causing bacteria to stick. That would indicate that fluoride contributes to making it easier for teeth to be washed of decay-causing bacteria by saliva, brushing and other activity. The article can be accessed via the “publications” link at www.acs.org.
(Sources: American Chemical Society, Langmuir and Science News Daily)