What Are Tooth Roots?
The tooth roots are the part of the tooth inside the bone socket. They’re covered by a connective tissue known as cementum, which is hard, but not as hard as tooth enamel. So, if the tooth roots are exposed, the cementum can quickly decay or wear away with brushing.
Tooth roots contain dentin and nerve pulp, so if the cementum is worn out, the dentin's tubules allow hot, cold, acidic, or sticky foods to stimulate the nerves inside the roots, causing sensitivity.
So how are the nerves in your tooth roots exposed? The root of a tooth is typically covered and supported by gum, cementum, and bone. If this support disappears, the root is exposed, and ultimately the nerves inside the tooth roots are exposed.