5 Root Canal Myths Debunked by an Endodontist

Root canal treatment has a reputation problem, and most of it traces back to either century-old debunked research or the pre-anesthesia era of dentistry. Modern endodontics has a success rate in the 90 to 95 percent range, is typically no more uncomfortable than a routine filling, and is the most reliable way to save a natural tooth that has been damaged from the inside. Below are five of the most persistent root canal myths and what the current evidence — from endodontic specialists and the major dental science bodies — actually shows.

Myth 1: Root canals are extremely painful

This is the myth we hear most often at our Belmont practice. It traces to real history — root canals performed before modern local anesthesia genuinely were uncomfortable — but the procedure today is well-controlled. The dentist or endodontist numbs the area with local anesthetic, isolates the tooth with a thin protective sheet called a dental dam, and uses very fine instruments to clean out the infected or damaged pulp. Most patients describe the visit as comparable to having a cavity filled.

Surveys conducted by the American Association of Endodontists have consistently shown that patients who have actually had a root canal are several times more likely to describe the procedure as painless than patients who have only heard about it. The throbbing sensation people associate with root canals is almost always the toothache that preceded treatment — the procedure is what makes that pain go away. Mild tenderness for a few days afterward is normal and usually responds to over-the-counter pain relievers.

Myth 2: Root canals cause cancer or systemic illness

This claim resurges online every few years, often citing a documentary that Netflix removed in 2019 after major dental organizations flagged it as misinformation. The underlying idea is called the focal infection theory, proposed by Weston Price in the early 1900s, which suggested that bacteria from treated teeth could migrate through the body and cause everything from arthritis to heart disease.

The original research used methods that would not pass any modern review — implanting extracted teeth under rabbit skin with no proper controls, in an era before microbiology was well understood. Well-designed studies starting in the 1930s already discredited those findings, and contemporary clinical research comparing patients with extensive endodontic work to those without has found no increased risk of cancer, heart disease, or autoimmune conditions. The American Dental Association's scientific division has reaffirmed that endodontic treatment performed by qualified clinicians does not cause systemic disease.

Myth 3: It is cheaper and simpler to just pull the tooth

On the day of the procedure, extraction may be faster, but the long arc of care almost always favors saving the natural tooth. When a tooth is removed, the bone underneath begins to resorb within months. The teeth on either side drift toward the gap, and the opposing tooth can start to over-erupt. Replacing a missing tooth properly typically means an implant or a bridge — and either of those, plus the restorative work the neighboring teeth eventually need, tends to add up to substantially more time, biology, and money than treating the original tooth.

Carlmont Dental Care sits on the higher end of Bay Area pricing because of our materials and clinical time, and we want patients to see the full menu of options. We accept most PPO plans, offer in-house membership plans starting at $30 per month, and partner with CareCredit and Proceed Finance for 0% APR financing — so cost on its own should not be the reason a savable tooth gets pulled.

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

Nothing is pulled out of the jaw during a root canal. The roots — the long anchors that hold the tooth into 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 space is then cleaned, shaped, filled with a biocompatible material called gutta-percha, sealed, and topped with a crown or filling. The tooth remains anchored, capable of chewing, and indistinguishable to a casual observer from any other tooth in your mouth.

Myth 5: No pain means no root canal is needed

A tooth can need endodontic treatment without hurting at all. Pulp can die quietly, especially after old trauma, deep restorations, or a fracture that did not seem like a big deal at the time. When that happens, the body can wall off a chronic infection at the root tip that is only visible on an x-ray. Left untreated, those silent infections can flare into an abscess or slowly erode the surrounding jawbone.

This is one of the reasons routine exams matter. During a checkup, your dentist may do a cold test, gently tap on a tooth, or look at a periapical x-ray to assess pulp health on a tooth that feels completely normal. Catching a non-vital tooth early is much better than catching it during a midnight abscess.

Common questions about root canals

Q: How long does a root canal take?

Most are completed in one or two visits, each lasting about 60 to 90 minutes, depending on which tooth is involved and how curved the roots are.

Q: Will I need a crown afterward?

Most back teeth (molars and premolars) do, because they handle heavy chewing forces and a treated tooth can become more brittle over time. Front teeth sometimes need only a permanent filling.

Q: How long will the treated tooth last?

With a good final restoration and routine home care, root-canal-treated teeth often function for decades. Endodontic specialty literature consistently reports success rates in the 90 to 95 percent range.

Q: Does insurance cover it?

Most PPO plans we accept — including Delta Dental PPO, Aetna, MetLife, Cigna, and Guardian — cover a portion of endodontic treatment. We give patients a written estimate before treatment so there are no surprises.

Q: Will I be loopy or need a ride home?

No. Local anesthesia only numbs the treatment area. You will be alert and able to drive yourself home and back to work the same day.

If you have been told you need a root canal — or you have a tooth that simply does not feel right — we are happy to take a careful second look. Our team at Carlmont Dental Care in Belmont serves patients from San Carlos, San Mateo, Redwood City, and across the Peninsula, with Mandarin- and Spanish-speaking staff available. Call (650) 591-1984 or visit carlmontdentalcare.com to schedule a consultation, and we will review your imaging, walk through what is actually happening with the tooth, and put together a written plan.