Five Root Canal Myths, and What the Evidence Actually Says

Root canal treatment carries a reputation it has not earned, much of it inherited from long-discredited research or from dentistry before modern anaesthesia. Today, endodontic treatment succeeds in roughly 90 to 95 percent of cases, typically feels no worse than having a routine filling, and remains the most dependable way to keep a natural tooth that has been damaged from within. Here are five of the most stubborn myths, alongside what current evidence from endodontic specialists and the major dental science organisations tells us.

Myth 1: A root canal is agonising

This is the concern we hear more than any other. It has a basis in history, since root canals performed before modern local anaesthetic really were uncomfortable, but the procedure today is carefully controlled. The area is numbed with local anaesthetic, the tooth is isolated with a thin protective sheet called a dental dam, and very fine instruments are used to clear out the infected or damaged pulp. Most patients say it feels much like having a cavity filled.

Surveys by the American Association of Endodontists have repeatedly found that people who have actually had a root canal are several times more likely to call it painless than people who have only heard about one. The throbbing pain associated with root canals is nearly always the toothache that came beforehand; the treatment is what relieves it. Some tenderness for a few days afterward is normal and usually settles with over-the-counter pain relief.

Myth 2: Root canals cause cancer or other illness

This idea resurfaces online every few years, frequently citing a documentary that Netflix withdrew in 2019 after major dental organisations flagged it as misinformation. It rests on the focal infection theory, put forward by Weston Price in the early 1900s, which proposed that bacteria from treated teeth could travel through the body and cause conditions ranging from arthritis to heart disease.

The original work relied on methods that would not survive modern review, such as placing extracted teeth under the skin of rabbits without proper controls, at a time when microbiology was poorly understood. Better-designed studies had already discredited those findings by the 1930s, and present-day clinical research comparing people with extensive root canal treatment to those without has found no higher risk of cancer, heart disease or autoimmune conditions. The American Dental Association's science division has reaffirmed that endodontic treatment performed by qualified clinicians does not cause systemic disease.

Myth 3: Taking the tooth out is cheaper and easier

An extraction may be quicker on the day, but over the long run saving the natural tooth nearly always comes out ahead. Once a tooth is removed, the bone beneath it starts to shrink within months. Neighbouring teeth lean into the space, and the tooth opposite can begin to over-erupt. Replacing the missing tooth properly usually means an implant or a bridge, and either one, together with the work the adjacent teeth may eventually need, generally adds up to considerably more time, biological cost and expense than treating the original tooth. If you are weighing the two paths, our comparison of implants and bridges shows what replacement involves.

We always want patients to see every option clearly, with a written estimate before treatment. Cost alone should never be the reason a tooth that can be saved is removed.

Myth 4: A root canal removes the roots or kills the tooth

Nothing is taken out of the jaw during a root canal. The roots, the long anchors holding the tooth in the bone, stay exactly where they are. What is removed is the soft tissue inside the tooth, the pulp, which contains nerves and small blood vessels. That inner space is cleaned, shaped, filled with a biocompatible material called gutta-percha, sealed, and then covered with a crown or filling. The tooth stays firmly anchored, continues to chew normally, and looks like any other tooth to a casual observer.

Myth 5: If it does not hurt, it does not need treatment

A tooth can need root canal treatment without causing any pain. The pulp can die quietly, particularly after an old injury, a deep filling or a fracture that seemed minor at the time. When that happens, the body may wall off a low-grade infection at the tip of the root that shows up only on an X-ray. Left alone, these silent infections can flare into an abscess or gradually wear away the surrounding bone.

This is one reason routine examinations matter. At a checkup we may carry out a cold test, tap gently on a tooth, or take a periapical X-ray to check the health of a tooth that feels perfectly normal. Finding a non-vital tooth early is far preferable to discovering it through an abscess in the middle of the night.

Common questions about root canals

How long does it take?

Most are finished in one or two appointments of about 60 to 90 minutes each, depending on which tooth it is and how curved its roots are.

Will I need a crown afterward?

Back teeth (molars and premolars) usually do, as they take heavy chewing forces and a treated tooth can grow more brittle over time. Front teeth sometimes need only a permanent filling, and in many cases a same-day crown is an option.

How long will the tooth last?

With a sound final restoration and good home care, teeth that have had root canal treatment often work well for decades. The endodontic literature consistently reports success rates of 90 to 95 percent.

Does insurance cover it?

Many PPO plans cover part of endodontic treatment. Eclat is in-network with all major PPO dental plans, and we provide a written estimate beforehand so there are no surprises.

Will I need someone to drive me home?

No. Local anaesthetic numbs only the treatment area, so you will be alert and able to drive yourself home or back to work the same day. If nerves are the bigger issue, our guide to comfort options for anxious patients explains what is available.

A careful second look

If you have been told you need a root canal, or a tooth simply does not feel right, we are happy to take a careful look. Our endodontics page explains how we approach treatment. Call Eclat Dental Studio in Mountain View at (650) 917-8348, and we will review your imaging, explain what is happening with the tooth, and prepare a written plan.