How Root Canals Generate Toxins 

Dr. Weston Price spent 35 years of his professional career in research. He was the former director of research for the American Dental Association, a position he held for 14 years. His special interest was systemic diseases. He studied diseases of the heart, kidney, uterus, nervous system and endocrine system resulting from toxins seeping out of root canal filled teeth. He became aware that a certain percentage of people are sensitive to toxins that are manufactured within these dead teeth. This research was done prior to 1920.

The treatments he researched are basically the same treatments that are the foundation of today's root canal work. Research convinced Dr. Price of many truths that we still have a hard time seeing, even today. We remain bogged down in "that's the way we've always done it" thinking. We have been too habitual to adopt this sense of new "truth".

His extensive research covered 24 procedures. Each of the 24 procedures was found lacking. In those days, before extensive use of x ray, the infection in the root canal went unnoticed or disguised itself as bone absorption. local comfort of a treated tooth was taken as a sign of success of the procedure. Only the dangerous sign of pus flowing from a tooth was taken as a sign of failure. However, Dr. Weston Price looked beyond the obvious.

What did Price find in his research that convinced him that people could not tolerate root canals?

First he observed that when root filled teeth were removed from people suffering from kidney and heart disease, most improved. in an effort to establish the relationship between the tooth and the disease, he inserted the root filled tooth under the skin of a rabbit. Rabbits were chosen because they have a similar immune system to humans. Dr. Price established that a normal tooth can be inserted under the skin of a rabbit for a year with practically no reaction. A thin film will form over it, but microscopically there are no rejection cells present.

Rabbits died within 48 hours when a root filled tooth was implanted under the skin. Each rabbit implanted with a root filled tooth would die of the exact same disease as its human donor. Each lime a tooth, or fragment of a tooth, was passed from one rabbit to another, the death of the human donor was duplicated. In experimental lab cases, Dr. Price transferred the fragment from 30 to 100 rabbits in succession. If a small fragment was used, the rabbit would lose over 20% of it's body weight within two weeks.

Even so Dr. Price's research was mostly ignored and dentists continued to use root canal procedures to save human teeth. Dr. Percy R. Howe was the first to publish a paper in the Journal of National Association for Dentists rejecting Price's findings. Howe injected large amounts of bacteria (streptococcus) into rabbits and found no adverse reaction. This 1920 publication is still used as proof that root filled teeth are not harmful to humans. In searching for a reason for the difference between Howe's finding and his own, Dr. Price investigated the methods of sterilization of root canals, (very much the some as today's technology). His findings proved that teeth retained their sterility for only about two days after the roots were filled.

Where was the bacteria hiding?

A tooth contains enamel, dentin an a central pulp chamber. The central pulp chamber can be sterilized to a reasonable degree by removing Its contents of nerves, arteries, and veins and flushing it with 27 chemicals. The dentin, however, is composed of thousands of tiny “dentine tubules” that are unreachable by this flushing procedure. Although microscopic in size, these tubules are quite adequate to house billions of bacteria. If one were to take a front tooth and arrange the dentin tubules end to end, they would reach for 3 miles. The tubules are wide enough to accommodate 8 streptococci abreast.

They are of the Streptococcus Viridians family and are normal inhabitants of the mouth. When a tooth becomes decay prone, they invade the tooth and start killing tooth tissue. When they reach the pulp chamber, they invade not only the pulp tissue, but also the dentin tubules. When a dentist cleans out the pulp chamber, he removes all the bacteria in the chamber, seals the tooth, and that's when a new action begins; that points out Howe's misinterpretation!

In an "anaerobic" condition, or one that contains no oxygen, these Streptococci mutate, undergoing a slight change in a body form and metabolism to adapt to this new environment. Now, instead of producing slightly offensive waste products, these transformed bacteria produce a potent poison called a TOXIN.

Our immune system does not like the toxins but the cells of our immune system cannot get in to the tiny holes in the outside of the root to destroy the bacteria. Toxins can seep out. Fluids containing nutrients can seep into the tooth, so the bacteria continue to thrive in confinement. If the body launches a big fight against the toxins, pus forms around the tooth.

Conventional wisdom says that pus is bad for the patient and dentists give antibiotics until it's gone. Price found the pus to be nearly sterile, although socially disagreable.

Its presence was the sign of successful quarantining the toxins from the tooth. That was certainly a new idea and one which was not readily accepted. Another disturbing situation uncovered by Dr. Price was that x rays frequently miss abscesses found on the front or back of a tooth. About 30of teeth have extra canals which may exit anywhere from half way down the tooth, to all the way down at the tip like they are supposed to. They can exit on the front, back, or side of the tooth. Those "other" canals that abscess are the ones that are opt to be missed on the x ray.

Q. What about root-filled teeth that do not form pus or give pain?

If the body's immune system is compromised, then very little action is initiated around the root-filled tooth. Certain enzymes may escape which stimulate the bone to form what is termed "condensing osteitis" around the tooth. On x-ray films, this will appear as a white line and is considered to reflect excellent healing. This tooth gives no trouble locally as far as pain and pus are concerned, but the toxins that seep out get into the body's circulation, and with little immune system interference, seek a specific organ to attack. Dr. Price named this "tissue localization." Price demonstrated this by transferring sections of root-filled teeth, with animals generating the same disease with each transfer.

Q. What is the factor that determines who is the most susceptible to problems from root canals?

Dr. Price recorded 140,000 determinations in 1200 patients to come up with his answers to this question. Bottom line, it is heredity. If your biological inheritance for two generations, including brothers and sisters of your grandparents, were resistant to degenerative diseases, than you are not apt to launch an immune response against a root canal. On the other hand, if there was a high frequency of heart, kidney, diabetes and reproductive disorders, then you are more apt to be susceptible. 

Q. Sometimes a person of healthy genetic stock can develop diseases as a result of reactions to most root-filled teeth. How does this happen?

Most of us are aware that the abuse of alcohol, drugs and caffeine stress our system. Dr. Price found there were other stresses that were just as great. Exposure to these types of stresses tend to push people over their threshold and allow the root canal tooth to become a problem. The challenge could exceed the person's resistance. The two greatest stresses, according to Dr. Price's research, were pregnancy and influenza (flu). Under the influence of either of these conditions, the toxins from root-filled teeth were much more apt to produce disease at the person's specific  susceptible site. Other stresses were grief, anxiety, chilling, severe hunger and acute chronic infection.

Q. If you have a root canal and want it removed, do you just pull the tooth?

No. This may lead to more problems. At the time these teeth are removed, the attachment from the tooth to the bone, called the periodontal ligament, must be removed with a dental burr as well. This irritated the old bone and stimulates it to form new bone. Recent studies at the University of Colorado looked at biopsies of bone under removed root-filled teeth. Lymphocytes of auto immune disease were embedded at least a millimeter into the bone, sometimes more. All this must be removed if good bone healing is to be achieved.

Dr. Price's research, published in many peer reviewed journals (ie: J.A.M.A., J.A.D.A.O.) has never been refuted. Commercial expediency has no doubt influenced professionalism in its apparent decision to ignore the research of one of our most brilliant scientific minds, to the detriment of an ever increasing proportion of the population.


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Hartzell and Henrici. The Dental Path - Its Importance as an Avenue of Infection. Surg. Gyn. and Obs. Jan 1914

Fillings, Focal Infections, J.A.M.A. Vol. 63, 1914.

Rosenow, Elective Localization of Streptoccoci, J.A.M.A. Vol. 65, no.20, p.2024, 1914.

Price, W.A. Dental Infections Oral Systemics, Vol. 1, Penton Publishing Co. (703 pages) 1923.

Mayo, Mouth Infections as a Source of Systemic Disease, J.A.M.A. Vol. 63, p.2-25, 1914.

Price, W.A. Resolved that Practically all Infected Pulpless Teeth Should be Removed, J.A.M.A. Dec. 1925.

Price, W.A. Dental Infections and Degenerative Diseases, Penton Publishing Co. (471 pages) 1923.

Reese and Beigher, Subacute Combined Degeneration of the Spinal Cord in Pernicious Anemia. Amer. Journal, Med. Sci. Feb. 1926.

Price, W.A. Dental Infections and Related Degenerative Diseases. J.A.D.A. Jan. 24, 1925.

Price, W.A. The Pathology of Dental Infections and Relation to General Diseases. Report of the Canadian Oral Prophylactic Association. Feb. 1916.