Understanding Your Dentist: Cavities and Root Canals

Anyone who has been to the dentist has heard of and probably had at least one procedure done to save a tooth. As commonplace as cavity fills and root canals are, it is hard to imagine a tooth being alive and how it ends up being infected. Still, it's important to understand how your teeth work and how they can get infected. If you do not want to be left in the dark the next time you visit the dentist, read on to find out about tooth structure, fillings, and root canals.

The tooth can be broken down into two main parts: the crown and the root. The crown consists of the part of the tooth that can be seen from the outside. It protrudes out from the gums and is covered in enamel. Enamel is the hardest substance in the human body and provides the tooth's toughest layer of defense against hard foods. Underneath the enamel is a tissue called dentin. Dentin is not as hard as enamel, but not as soft as most human tissue. At the very heart of the tooth is a tissue called the pulp. The pulp is a soft connective tissue that provides nutrients to the rest of the tooth.

The other half of the tooth is embedded deep into the gums to hold it in place and is referred to as the root. The root is mostly comprised of dentin and extends like prongs deep into the gums. At the tip of each prong blood vessels enter the tooth and connect to the pulp. Without these vessels intact to deliver nutrients to the pulp, the tooth will die. Most of the work that a dentist does aims to prevent the pulp from being damaged so that the tooth will not be lost.

Tooth decay occurs naturally. Bacterial deposits form on the outermost layer of the crown and, if left untreated, will eat away at the enamel and eventually the dentin. This deterioration forms a hole in the tooth known as a dental cavity. Once a hole has been made in your tooth the enamel and dentin will not regrow, so the hole must be replaced with a hard substance known as a filling. Sometimes the cavity forms at the top of the tooth and an entire new surface must be created- this is called a crown.

A root canal is needed in more dire situations. When a cavity has reached the pulp and infected it, it is usually necessary to completely remove the pulp. During a root canal procedure, the dentist drills into the tooth from the top, removes the pulp, and fills the tooth with a synthetic substance. When the tooth is sealed on top with a crown, it is technically dead, although it will not be lost because the bacterial infection is stopped.

These two common dental problems both result from basic bacterial infections. Brushing and flossing helps reduce buildup of bacteria on the teeth, and regular trips to the dentist can catch small cavities before they turn into larger, more dangerous problems.