Fluoride & Tooth Decay

Tooth enamel is hard and porous. It consists of many closely-packed rods made of minerals. When you eat, acid forms on the outside of the tooth and seeps into the enamel pores. This demineralization process can produce a weak spot in the tooth surface. If unchecked, the enamel can decay and create a cavity.

Fluoride and fluoride treatments help prevent tooth decay by slowing the breakdown of enamel and speeding up the natural remineralization process. These microscopic views of the tooth chewing surface show how fluoride works:


 a2A_1  a2A_2  a2A_3
Healthy tooth enamel rods
before acid onslaught.
Enamel rods demineralized,
or broken down, by acid.
Enamel rods remineralized,
or rebuilt, by fluoride and the
minerals in saliva

Common sources of fluoride are fluoridated drinking water, toothpaste and mouth rinse. Inform your dentist if your drinking water is not fluoridated. High concentration fluoride gels, mouth rinses, drops and tablets are available by prescription.

When your dentist detects a weak spot on your tooth, at-home fluoride treatments may be recommended to reverse the decay process. If the weak spot is left unchecked, a cavity may form, necessitating a filling. If decay is allowed to spread, it may penetrate the root and enter the pulp (nerve) chamber, causing an abscess and requiring root canal treatment.

Progression of tooth decay


b2B_1 b2B_2 b2B_3 b2B_4
Tooth decay often begins
on biting surfaces,
between the teeth,
and on exposed roots.
Untreated,
the cavity becomes larger.
Decay spreads
beneath the enamel and can
destroy the tooth structure.
Decay enters the pulp,
and an abscess may occur.

Use of fluoridated toothpaste can help prevent tooth decay at its early stage.