How Long Will a Root Canal Last? (And How To Make It Last Longer)

A root canal removes infected or damaged pulp inside the tooth, then seals it off to prevent further issues. Dentists use it to stop pain and avoid extractions, all while preserving your bite and natural appearance.

Understandably, many patients want to know: after going through all that, how long will the results actually last?

According to a 2022 study conducted by the Regenstrief Institute and Indiana University School of Dentistry, teeth treated with a root canal survived an average of 11.1 years across a large patient sample.

The study, which analyzed electronic health records of over 46,000 patients, provides one of the most comprehensive insights into long-term outcomes, and it shows root canals can offer far more than just short-term relief.

What Really Determines How Long a Root Canal Lasts?

Not all root canals are created equal. Some last a lifetime. Others fail within a few years. The difference often comes down to a handful of specific factors that directly influence longevity.

Understanding these gives anyone undergoing endodontic treatment a clear idea of what to expect.

Tooth Location: Molars vs. Incisors

The type of tooth treated significantly affects the outcome. Molars have more complex anatomy and multiple canals, which makes them more difficult to clean, shape, and fill thoroughly.

According to the American Association of Endodontists (AAE), root canals performed on molars fail at a higher rate than those done on single-rooted teeth like incisors or canines. The posterior location also makes moisture control and access more challenging.

Crown Placement After Treatment

A root-canaled tooth without a crown is exposed to a much higher risk of fracture and bacterial contamination. Researchers at the University of Washington School of Dentistry found that root canal-treated teeth restored with crowns were six times more likely to survive than those without. Molars specifically require full coverage from a crown to withstand chewing forces.

Quality of the Final Restoration

The long-term prognosis heavily depends on how well the tooth is sealed after treatment. A well-fitted crown or filling prevents reinfection by blocking bacteria from re-entering the canal system. Inadequate restoration, with marginal gaps or weak bonding, can lead to leakage, recurrent decay, and eventual failure. The margin fit, material used, and the timing of the restoration work all matter.

Skill of the Dentist or Endodontist

Experience affects outcome. Cases handled by endodontists, specialists who perform root canal therapy exclusively, to have better root canal success rates.

A 2015 study published in the Journal of Endodontics reported that treatments performed by specialists resulted in fewer procedural errors and higher 10-year survival rates.

Oral Hygiene Practices

Patients who brush twice daily, floss, use antimicrobial rinses, and attend regular cleanings dramatically reduce the chance of a recurring infection around the treated tooth. In contrast, poor hygiene invites plaque buildup and gum inflammation, which, in turn, can affect surrounding bone and the tooth’s stability.

Pre-Existing Bone Loss or Deep Decay

Teeth with advanced decay into the root or significant bone loss around them due to periodontal disease face higher failure risks. Healing capacity may be compromised, and the support structure may already be weakened before treatment begins.

These teeth may still be saved with root canal therapy, but the long-term outlook differs from a case treated early.

• Molars are more complex to treat and more prone to failure than front teeth.

• A dental crown after the root canal boosts survival rates significantly.

• Restoration quality is critical for sealing out bacteria.

• Experienced specialists deliver higher longevity outcomes.

• Consistent oral hygiene reduces the odds of re-infection.

• Existing decay or bone loss at time of treatment limits potential lifespan.

Should I consider a Dental Crown After a Root Canal?

A root canal removes the infected pulp, but the procedure doesn't restore strength. Once the pulp is gone, the tooth becomes brittle and vulnerable to cracks or full fracture under normal bite pressure.

That’s where a dental crown steps in.

Cemented over the treated tooth, the crown acts like a helmet, it absorbs the stress of chewing and keeps the underlying structure intact. Without this protection, a root canal-treated molar has up to a sixfold increase in fracture risk.

Dental crowns are foundational to long-term function. Learn more about how crowns are placed and how they protect the tooth.

Preventing Fracture and Extending the Tooth’s Lifespan

A study in the Journal of Endodontics (2020) found that posterior root canal-treated teeth restored with a full crown had a survival rate of over 85% at ten years, compared to only 59% for those without a crown. That 26-point difference doesn't happen by chance. The crown prevents vertical root fractures, which are almost always non-repairable and lead to extraction.

Front teeth may not always need a crown if they don’t endure significant bite force, but any premolar or molar does, without exception. Skipping a crown will shorten the life of the root canal-treated tooth significantly.

Daily Habits That Extend the Life of a Root Canal Tooth

To protect your tooth after a root canal, use a soft-bristled toothbrush and brush gently for a full two minutes, twice a day. Focus on reaching the gumline and cleaning around the crown or restoration.

Floss daily to remove plaque between teeth, especially near the treated area, where food particles can settle and increase the bacterial load that threatens long-term success.

Electric toothbrushes approved by the American Dental Association (ADA) can offer better plaque removal if manual brushing falls short.

Rethink What You Eat

Hard candies, unpopped popcorn kernels, and ice cubes exert pressure that can crack a tooth, even one protected by a crown. Sticky foods such as caramel, toffee, and gum can pull at restorations and lead to loosening or microleakage.

Once a treated tooth is sealed and restored, it doesn’t regenerate; any fracture or decay puts it back at risk.

• Cut raw vegetables like carrots into smaller pieces before eating.

• Skip overly chewy or sugary snacks between meals.

• Avoid chewing on one side exclusively; distribute bite force across your mouth.

Brush, Floss… Then What About Mouthwash?

Adding a therapeutic mouthwash to your routine can reduce bacterial buildup in places brushing and flossing may miss.

According to Open and Affordable Dental’s resource on mouthwash, the right formulation can support gum health and kill bacteria that lead to reinfection.

Choose an alcohol-free, antimicrobial rinse containing chlorhexidine, cetylpyridinium chloride, or essential oils if you’re enhancing your post-root canal care plan.

Stick to a Consistent Checkup Schedule

Dentists don’t just look for cavities. During routine dental exams, they assess the integrity of crowns and the health of the underlying tooth structure. This approach can catch issues early, before you see symptoms or feel pain.

According to Open and Affordable Dental’s guide to routine exams, patients who visit the dentist semiannually have better long-term results after procedures like root canals.

• Schedule exams every six months, even if your tooth feels fine.

• Report any unusual sensations near the treated tooth directly.

• X-rays every one to two years help detect internal changes.

Each of these actions supports the structure and health of your root canal-treated tooth. Minor adjustments in daily care, diet, and dental visits result in major gains in long-term success.

It’s not just about avoiding failure, it’s about making the restoration last decades.

Questions Patients Ask Most About Root Canal Length

How do I know if a root canal is failing?

Persistent pain is the most obvious sign. If the tooth aches weeks or even months after treatment, something’s wrong. Swelling, a pimple-like bump on the gum, tenderness when chewing, or a return of temperature sensitivity often indicate an unresolved or recurring infection. X-rays taken during a check-up often confirm the diagnosis by revealing dark areas around the root tip, evidence of lingering bacteria and bone loss.

What happens if I don’t get a crown after a root canal?

Without a crown, the tooth is left structurally weakened. Root canal treatment removes the pulp, making the tooth more brittle and prone to fracture under pressure. Molars and premolars, in particular, absorb significant bite force, if left uncrowned, they often crack. A cracked or broken tooth post-root canal usually cannot be saved, leading to extraction.

Can a root canal be redone?

Yes, retreatment is a standard endodontic option. When infection persists or returns, an endodontist removes the original filling materials, disinfects the inside of the canals again, and reseals the tooth. Retreatment may involve a microscope, ultrasonic tools, or CBCT imaging to locate hidden canals or microscopic fractures missed during the first procedure. Success rates for retreatment, while slightly lower than initial procedures, are still favorable, ranging from 70% to 88% depending on the case.