Both decay and periodontal diseases are infections caused by a number of specific bacteria which live in the plaque deposits. Brushing only allows these germs to thrive between the teeth, so flossing daily is imperative. The simple act of proper daily hygiene will prevent the majority of dental troubles in most people. Fluoride helps prevent decay in two ways. Fluoride molecules integrated into tooth structure, either systemically during development or topically once teeth are erupted, make the enamel more resistant to acid attack.
Bacteria use acid to dissolve tooth structure as the integral part of the de cay infection.
Fluoride is also toxic to many bacteria, including those involved in decay. Topical fluoride via toothpaste and rinses lowers bacterial counts significantly. This double whammy helps fluoride reduce decay to its current historically low levels in fluoridated communities. Always use fluoride toothpaste, and anyone with an increased risk of decay should use rinses. Fluoride rinses are most effective if used at bedtime.