Root Canal Treatment

Root Canal - An Outline of Treatment Options

• What Is Root Canal Treatment?
• Saving Teeth through Root Canal Therapy
  
  • What is root canal therapy?
  • What happens when the pulp is damaged?
  • What does root canal therapy involve?
  • Basic concerns of the patient!
  • The focal infection theory
• Some Key Questions
• What Are the Alternatives to Root Canal Treatment?

What Is Root Canal Treatment?

When the nerve in a tooth dies (either because of decay or trauma) the dead tissue is removed from the canal, medicaments such as antiseptics and localised antibiotics are used to clean the inside of the tooth and the canals are filled.

The problem is that it is impossible to make the tooth canals sterile. So, how significant is this to a person's health? The answer is we are not sure and the effects vary from individual to individual and within the same person from time to time. Broadly speaking there are two views:

• One view is that the bacteria and toxins pose a threat to a patient's health and that the bio-energetics of having a dead tooth on a meridian line (see Neural Therapy) has implications for a person's health
• The other view is that if a root canal treatment is well done by traditional dental standards then any exposure that a patient has to bacteria and their toxins is minimal and adequately dealt with by the body's immune system. Additionally that while the nerve in the tooth is no longer present the tooth is still sitting in bone and periodontal ligament that is still very much alive.

Even in the often quoted book Root Canal Coverup by George Meinig which reviews the work of Weston Price in the 1920's which raised serious questions about root canal treatment. Two significant statements from the book are often overlooked. Firstly, "... Price found that 25% of patients with family histories free of degenerative diseases who had excellent immune systems could expect to have and retain root canal fillings and to live without complications arising therefrom through old age". Secondly he identifies " that Price's studies were done before the time of calcium hydroxide which were found to kill most strains of bacteria in one minute".

At the Sydney Dental Centre we believe that each decision on whether or not to do root canal treatment is made on an individual basis. This must take into account the patients general health status at the time, reviewing that decision at each check up and deciding what the implications are of the alternatives to RCT

Inside every tooth is the dental pulp, which consists of nerves and blood supply.

Its main role is in the growth of the tooth. It also helps detect changes in temperature.


The pulp may become inflamed and die. This usually occurs as a result of decay and/or trauma. This can sometimes be painful (acute pulpitis or abscess) or can occur without any pain at all and go on for years undetected (chronic periapical abscess) until it becomes painful or is detected from X-ray examination.

When the pulp dies, dead tissue sits inside the tooth (gangrene) and because there is no blood supply to fight the bacteria and toxins, this reservoir of infection remains inside the tooth. A root canal treatment attempts to clean out the inside of the tooth. Ideally the tooth should be sterile.

Decay or trauma causes the nerve to die. Trauma may be a blow to the tooth or imbalance in the bite with a grinding or clenching habit.

Toxins from pulp bacteria cause inflammation and infection in the bone which may be painful (acute abscess) or may have no pain associated with it (chronic abscess)

The main canals are identified, measured, cleaned and washed out, dressed with antiseptics and anti-inflammatories and eventually filled with a powerful antiseptic.

Canals are measured, mechanically cleaned with files and irrigated with antiseptic solutions of hydrogen peroxid, Milton's and EDTA. Then dressed with calcium hydroxide.

There are  alternatives to gutta percha which which are similar to compostie resin filling materials. The issue of dentinal tubules is still a challenge.

A tooth without nerve and blood supply dries out and becomes brittle and needs to be strengthened.

The tooth often requires a crown for strength.

In the past post, core build-ups and crowns were three separate parts.

Each separate part introduces and inherent weakness.There is some question as to whether posts strengthen the tooth or not.

With a CEREC restoration the post,core and crown are milled to the exact shape of the remaining tooth as one homogeneous porcelain restoration and bonded to the tooth.

CEREC endodontic crowns incorporating post, core and crown in one is an excellent way of reinforcing and strengthening the root canal fill tooth.

Saving Teeth through Root Canal Therapy

What is root canal therapy?

Within each natural tooth, there is a formation of soft tissue, referred to as dental pulp; it contains nerves, arteries, veins, and lymph vessels. If you were to look at a cross section of a tooth, the exterior surface of the crown is the enamel, followed by a tissue called "dentin." Dentin is the bone-like tissue that supports the enamel and makes up most of the tooth structure. Within the dentin lies the dental pulp tissue. The pulp extends from a pulp chamber in the crown of the tooth (that portion of the tooth visible above the gums) down to the tip of the root, being contained in what is referred to as the "root canal." Although teeth can have more than one root, molars for example have two or three roots with root canals in each root, all teeth have only one pulp chamber.

In the early part of this century, when a tooth would become diseased or the dental pulp was injured, the accepted treatment was to extract the tooth. However, beginning in the late 1950's teeth with infected or injured dental pulp were being successfully saved using a procedure called endodontics, or root canal therapy. There is little question that the public's acceptance of endodontic treatment is on the rise. In 1969, for example, it was estimated that six million root canal fillings were being done each year. That number has now risen to about twenty-five million and by the year 2000, it is estimated that 30 million root canals will be filled annually.

What happens when the pulp is damaged?

When the pulp is diseased or injured, your body will attempt to repair and heal itself. However, if it is unable to repair the diseased or injured pulp, the pulp dies. This is normally caused by bacteria gaining access tot he pulp chamber, either through a fractured tooth or a deep cavity, which can expose the pulp to the bacteria found in your own saliva. The presence of bacteria in the pulp causes an infection inside the tooth. Left untreated, this infection can abscess, which is a buildup of infectious material (pus) at the root tip, eventually causing the pulp to die and the supporting bone surrounding the tooth will be destroyed.

What does root canal therapy involve?

Root canal therapy involves the various procedures used by the endodontist (root canal specialist) or dentist to save the tooth from having to be pulled, by removing the infected or diseased pulp from the tooth. In simple terms, the pulp chamber and root canal(s) of the tooth are cleaned, sterilized, and sealed to prevent recontamination of the root canal system. Although the treated tooth is no longer vital (you won't be able to feel pain or hot or cold, etc.) you have achieved several advantages:

1. The tooth was not removed leaving an empty space, which if left empty would cause teeth next to or opposite the empty space to begin shifting from their normal position. Shifting can cause teeth to become crooked or crowded, causing alignment problems that may eventually result in even more teeth being lost.
2. Your natural tooth has been retained maintaining the normal cosmetic appearance of your teeth.
3. Eliminates the need to have a replacement tooth (bridge) put in place of the removed tooth. Bridges are normally expensive and may also require extensive work on adjacent teeth for retention of the bridge.

Basic concerns of the patient!

Individuals undergoing root canal therapy for the first time usually have great apprehension and many concerns: Is the procedure painful?; Will this tooth have to be extracted later?; How long will the tooth last?; Will it turn black?, etc. From the patient's standpoint, it is easy to see how these concerns would exist.

• Normally the procedure is painless, as your dentist will use local anaesthesia prior to starting to work on the tooth.
• Most restored teeth will last as long as your natural vital teeth. The reason for this is that as long as the root(s) of the endodontically treated tooth are properly nourished by the surrounding tissues, your tooth will remain healthy. It is somewhat of a paradox in that most people think that a root canalled tooth is a dead tooth. However, it is not a "dead tooth" as long as the roots of the tooth are embedded in healthy surrounding tissues that bathe the external surface and offer it nutrition.
• For this same reason, it is seldom that a tooth will turn black. If appearance does become a prime concern, the tooth may be bleached or veneered (having a porcelain or composite facing placed over it). Most often, retention of the tooth and bleaching, veneering, or crowning are preferable to extraction and replacement with a prosthetic appliance (artificial tooth).

The focal infection theory

Although there exists a great deal of controversy regarding the success of endodontic therapy, the scientific facts at the present time are that only about 10% of root canal treated teeth experience some type of failure. The controversy over endodontic treatment is not new. Beginning in about 1912, there was wide acceptance of the theory of "focal infection" which resulted in the wholesale extraction of both vital and pulpless teeth. It wasn't until well after World War II, with the availability of improved x-rays, anesthetics, new methods and products, and the publication of the first major text book devoted to "Root Canal Therapy" that the "focal infection" theory lost favour. "Saving" rather than extracting the tooth became the "standard of care." Now however, the 1990's has seen a resurrection of the focal infection theory.

Lets look briefly at the "Focal Infection" theory. The main purpose of the dental pulp is to supply nutrients to the dentin as long as the tooth is alive. This is done through microscopic tubules in the dentin. To give you some indication of what is meant by microscopic, each tooth contains approximately 1.5 million tubules. As the living cells necrose (rot) within the central pulp chamber of an infected tooth, this same phenomenon is happening within the tubules. In theory, root canal therapy attempts to completely obliterate and fill the main pulp chamber and canals. However, it is impossible to fill the millions of microscopic tubules. Once inside the tooth, bacteria can remain within the tubules, growing and multiplying. Because microbes can change their form and function in response to a changed microenvironment within the tubules, they can go on living in spite of the altered oxygen and food supply. As they do so, they begin to produce various toxic chemicals, which have been shown to be harmful, sometimes being especially toxic to specific organs or organ systems.

Tronstad and associates confirmed this phenomenon in a recent 1987 study. They demonstrated that anaerobic bacteria (bacteria not requiring oxygen to survive) were able to survive and maintain an infectious disease in periapical (at the tip of the root) lesions of non-vital teeth. In a 1991 follow up study of endodontically treated teeth, these authors recovered micro-organisms from periapical lesion of all examined teeth.

The immediate question this raises is: If there are bacteria present from every endodontically treated tooth, why doesn't every root canal treated tooth become abscessed and fail? An oversimplification of the answer is that your own body's immune system is able to contain and neutralise the bacteria.

Dr. Weston Price, during the early 1900's, devoted most of his brilliant career to investigation of the focal infection theory. His research, involving thousands of patients and rabbits, formed the basis for the over 220 articles and 3 major books which he authored. In essence, the focus infection theory researched by Dr. Price holds that it is not the bacteria that causes systemic problems, but rather the toxic chemicals produced from the necrosis and decay within the tubules, whether the tooth had been endodontically treated or not. As a consequence of the fact that there was no way to completely seal the apex (tip of the root) and the tubules, the need to extract both vital and pulpless teeth, when an infection was evident, became the effective treatment.

There are now a group of dentists around the country who are openly advocating the extraction of every root canaled tooth on the basis of the research done by Dr. Price. This is certainly a radical approach to solving a problem that appears to be limited to only bout 10% of the total number of root canal treatments done. Furthermore, it certainly does not take into consideration the use of calcium oxide as a root canal medication in the treatment of infected root canals. Much of the current confusion in the minds of the public about the efficacy of root canal therapy has been precipitated by the book "Root Canal Cover Up" written by George Meinig, D.D.S., past president of the American Association of Endodontists. Dr. Meinig extensively cites the work of Dr. Price and concludes that there is a serious problem with root canal therapy and teeth that have had root canal treatment. This, of course, is a major break with his own previous training and the policies of both the American Association of Endodontists, and the American Dental Association. Patients going to an "establishment" endodontist or dentist who does not subscribe to the focal infection theory are given a much different picture on the efficacy of root canal treatment. Here again, establishment protocols for endodontic treatment rely heavily on the use of some very toxic chemicals and cements. And although there is a 90% success rate for most endodontic procedures, it is still a scientific fact that using the existing endodontic materials and techniques, there is no way to totally seal the apex of the tooth and the dentinal tubules. Bonded resin fillling materials instead of gutta percha may offer a solution.

Some Key Questions Relating to Root Canal

Question 1. Can we completely sterilise a tooth rendering it free of bacteria or their toxins?

The answer is probably no, it is certainly challenging. The problem is that the tooth is not simply 1, 2, or 3 canals but is made up of millions of little tubules that are wide enough for bacteria to live in and multiply.


There may also be accessory canals, curved roots and branches. Because of the structure of a tooth we may not be able to completely sterilise a tooth.

Curved & Incompletely Filled Canals

Accessory Canals

Incompletely Filled Canals

Question 2 How important is it to completely sterilise a tooth?

The answer is we're not sure. If you are in good health then it may have no observable effect. If you are in poor health which includes, cancer, diabetes, leukemia, malnutrition, vitamin deficiencies, diseases of the liver and kidney, and prolonged therapy with antibiotics and corticosteroids then the bacteraemia (bacteria and their toxins escaping into the blood) may adversely affect your health.

( from the reference list provided by the American Endodontic Association ; Baumgartner, Heggers and Harrison J Endodontics 2(5) 135-40 May 1976)

Despite the inability to completely sterilise a tooth the following two cases show areas of infection characterised by a dark shadow at the tip of the root. Some months after treatment there has been regeneration of bone suggesting a positive health out come.

The X-ray above shows a large abscess
at the tip of the root...

while this X-ray was taken 9 months later showing regeneration of bone.

Again extensive shadowing around the root shows evidence of infection, with root canal treatment in progress...

while the X-ray above taken 12 months later shows regeneration of the bone and healing, suggesting a positive health outcome.

What Are the Alternatives to Root Canal Treatment?

The alternative to RCT is to extract the tooth and thoroughly curette the extraction site (Note: this is standard for all extractions). When a tooth is extracted it should be replaced to maintain the harmony and balance of the teeth and jaw. The alternatives have there own potential problems and often may involve more extensive and expensive treatments.

These include:

• Removable partial dentures
  • These need to be removed and cleaned after every meal
  • Increases risk of periodontal disease (See Periodontal disease)
  • Increase wear and tear on adjacent teeth and gums that support the denture
  • Not as comfortable as your own teeth
• Fixed bridge work
  • Involves crowning teeth on either side of the missing tooth
  • Increases risk of periodontal disease (See Periodontal disease)
  • There is always the possibility of the nerve in a supporting tooth dying
• Titanium Implants placed in the jaw bone
  • Bio-energetics of placing a metal implant on a meridian line (See Neural Therapy)