Endodontics, or a root canal, is necessary due to an infection or injury to the nerve and blood vessels of the tooth. To understand endodontic treatment, it helps to know something about the anatomy of a tooth. Inside the tooth, under the white enamel and a hard layer called the dentin, is a soft tissue called the pulp. The pulp contains blood vessels, nerves, and connective tissue and creates the surrounding hard tissue of the tooth during development.
The pulp extends from the crown of the tooth to the tip of the roots where it connects to the tissues surrounding the root. The pulp is important during a tooth’s growth and development. However, once a tooth is fully mature, it can survive without the pulp because the tooth continues to be nourished by the tissue surrounding it.
Why Endodontic Treatment is Necessary
Endodontic treatment is necessary when the pulp becomes inflamed or infected. The inflammation or infection can have a variety of causes; deep decay due to bacteria, multiple dental procedures on the tooth, or a crack or chip in the tooth. In addition, trauma to a tooth may cause pulp damage even if the tooth has no visible chips or cracks. If pulp inflammation or infection is left untreated, it can cause pain, and/or lead to an abscess.
Signs of pulp damage include pain, prolonged sensitivity to heat or cold, discoloration of the tooth, and swelling and tenderness in the nearby gums. Sometimes there are no symptoms.
Treating the Tooth
A traditional endodontic procedure involves removing the inflamed or infected pulp, carefully cleaning and shaping the canals inside of the tooth, then filling and sealing the space inside the canal. Almost all root canaled teeth need a crown since a great amount of tooth structure is lost from the decay, which makes the teeth more susceptible to fracture. A crown serves to hold the tooth together and reduce the likelihood of the tooth fracturing in the future. Front teeth need crowns as a root canal tooth will change color over time and needs the crown for support against fracturing. We will not seal until any potential infection is gone.
Endodontic treatment can often be performed in one or two visits depending upon the cause of the root canal and the complexity of the tooth. Sometimes more visits are necessary. The first step is to examine, test, and x-ray the tooth and then numb the tooth with local anesthetic to eliminate or at least reduce any pain. We then use a hand piece to open access into the pulp chamber and root canals. Once access is made, very small instruments are used to clean and shape the pulp chamber and root canals to remove the nerve, blood vessels and connective tissue, and prepare the canals for the root canal filling material.
When a tooth is infected, the infection is inside the tooth and at the bottom of the tooth in the bone at the apex. There is no place in the human body where infections are immediately cleared up. Treating an infection takes time to control the bacteria. Opening a tooth, treating the root canal, and sealing it the same day may trap the infection at the bone at the bottom of the tooth. That is why, in this office, most root canals take multiple visits.
Filling the Canals
After the space is cleaned and shaped, we place medicine and temporary filling into the opened space and see the patient back in 4-7 days. We fill the root canals with a biocompatible material, usually with a rubber-like material called “gutta-percha”. The gutta-percha is placed with an adhesive cement to ensure complete sealing of the root canals.
The goal of the filling material is to create a barrier so that no cells, fluids, or other matter enters the tooth at the tip of the root. In some cases, a temporary filling is placed to close the opening. This temporary prevents anything from entering the tooth from your oral cavity. It is important that this temporary is replaced by a final restoration in a short amount of time.
Restoring the Tooth
After the root canal therapy is completed, a core build-up and a post will need to be made inside the tooth if the tooth lacks sufficient structure to hold a restoration in place. This will provide a solid foundation for a crown and fills the hollow space that was created to access the pulp and canals of the tooth. A crown or other restoration is then placed on the tooth to protect and restore it to its full function.
How a Tooth with a Simple Cavity Can Require a Root Canal
As the cavity progresses, it breaks through the enamel, which is the hard outer layer of tooth, and it enters the dentin, which is the layer of tooth beneath the enamel. The dentin is much softer and once the decay enters this layer, it spreads much faster as it progresses its way to the pulp.
Once the decay enters the pulp, you now have bacteria from your mouth that inhabit the root canal system and the by-products of that cause destruction of the surrounding bone, which can be a very serious situation and can cause both serious pain and your tooth to throb. At this point, you either need to have a root canal or have the tooth extracted. X-Rays are necessary because knots in the face muscles can affect tooth pain as well.