Historic Perspective of Endodontics

Endodontics is relatively a new branch in dentistry and my teacher used to call it the “youngest daughter of dentistry.” As such it will be interesting to view it from the historical angle.

In 1890, W.D. Miller associated the presence of bacteria with pulpal and periapical disease. E. C. Rosenow, in 1909 described the “Theory of Focal Infection” as a localized or generalized infection caused by bacteria traveling through the bloodstream from a distant focus of infection.

In 1910, a British physician, William Hunter, condemned the practice of dentistry in the United States, which emphasized restorations instead of tooth extraction. He believed that this was the cause of Americans’ many illnesses, including pale complexion, chronic dyspepsias, intestinal disorders, anemias, and nervous complaints. Soon pulpless teeth (teeth with necrotic pulps) and endodontically treated teeth were also implicated. The practice of root canal treatment suffered a severe set back for almost 40 years as a result of hypothesized association between oral focal sepsis and systemic illness.

In 1939, Fish recognised four zones of reaction formed in response to viable bacteria implanted in the jaws of guinea pigs. He described the bacteria as being confined by polymorphonuclear neutrophil leukocytes to a zone of infection. Outside the zone of infection is the zone of contamination containing inflammatory cells but no bacteria. Next, the zone of irritation contained histocytes and osteoclasts. On the outside was a zone of stimulation with mostly fibroblasts, capillary buds, and osteoblasts. Fish theorized that removal of the nidus of infection would lead to resolution of the infection. This theory became the basis for successful root canal treatment.

Today the medical and dental professions agree that there is no relationship between endodontically treated teeth and the degenerative diseases implicated in the theory of focal infection. This body of research of focal infection theory based on the poorly designed and outdated studies has been evaluated and disproved. Unfortunately, uninformed patients may receive this outdated information and believe it to be credible new findings, so it's the duty of the clinicians to make the patients understand and impart them with the logical information.