Many people associate root canal infections with unbearable tooth pain.

While severe pain is certainly one possible symptom, it is not the only warning sign—and sometimes there is no pain at all.

A tooth can become infected gradually. In some cases, the nerve inside the tooth dies, eliminating pain while the infection quietly spreads into the surrounding bone.

That is why recognizing the symptoms of a root canal infection early can make the difference between saving a tooth and losing it.

At my Henderson, Nevada practice, I encourage patients not to wait until the pain becomes unbearable. Early diagnosis often leads to more comfortable treatment and better long-term outcomes.

“Pain is only one way the body tells us something is wrong. A tooth can be seriously infected even when it’s relatively comfortable.”

— Marielaina Perrone, DDS

What Is a Root Canal Infection?

Inside every tooth is a small chamber containing soft tissue known as the dental pulp.

The pulp contains:

• Blood vessels
• Connective tissue
• Nerves

When bacteria enter this space through deep decay, a crack, trauma, or an old restoration. The pulp becomes inflamed and eventually infected.

Without treatment, the infection may spread beyond the root tip into the surrounding jawbone.

How a Root Canal Infection Develops

A root canal infection usually doesn’t happen overnight.

It often follows a gradual progression:

1. Enamel becomes damaged.
2. Bacteria reach the dentin.
3. Infection spreads into the pulp.
4. The pulp becomes inflamed.
5. The nerve tissue begins to die.
6. Infection moves beyond the root into the surrounding bone.

Understanding this progression explains why symptoms can change over time.

“The tooth often gives us several opportunities to intervene before the infection becomes extensive. Recognizing those early warning signs is incredibly valuable.”

— Dr. Marielaina Perrone, DDS

Common Symptoms Patients Notice

Many patients recognize certain symptoms long before they know the tooth needs treatment.

These include:

Persistent Toothache

Pain may be:

• Constant
• Intermittent
• Sharp
• Dull
• Throbbing

Some patients notice discomfort that seems to come and go over several weeks.

Pain While Chewing

An infected tooth often becomes tender when biting.

Patients may notice:

• Pain while chewing food
• Discomfort releasing pressure
• Difficulty biting on one side

This symptom may indicate inflammation around the root.

Sensitivity That Doesn’t Go Away

Most healthy teeth briefly respond to cold foods.

An infected tooth often behaves differently.

You may notice:

• Lingering sensitivity to cold
• Pain after hot drinks
• Temperature sensitivity lasting several minutes

Unlike normal sensitivity, the discomfort does not disappear immediately.

Swollen Gums

Localized swelling near one tooth may indicate infection.

The gums may appear:

• Puffy
• Red
• Tender
• Raised

Occasionally a small “pimple” develops on the gum tissue.

A Gum Pimple (Dental Abscess)

One of the clearest signs of infection is a small bump on the gums.

This bump may:

• Drain fluid
• Drain pus
• Come and go
• Reduce pressure temporarily

Although symptoms may improve temporarily, the infection remains.

Bad Taste or Persistent Bad Breath

An infected tooth sometimes drains through the gums.

Patients occasionally report:

• A salty taste
• A foul taste
• Persistent bad breath that brushing doesn’t improve

Tooth Discoloration

A tooth whose nerve has died may gradually darken.

Instead of appearing white, it may develop:

• Gray discoloration
• Brown discoloration
• Yellow-darkening compared with neighboring teeth

This change often develops slowly.

Symptoms Dentists Detect During an Examination

Patients notice one set of symptoms.

Dentists look for another.

During your examination, we evaluate:

• Tenderness to percussion
• Swelling around the root
• X-ray evidence of bone loss
• Deep decay
• Cracked teeth
• Existing restorations
• Pulp vitality
• Tooth mobility
• Sinus tracts

These findings help determine whether the pulp remains healthy or has become infected.

“A dental examination isn’t simply about finding cavities. It’s about understanding why a tooth is hurting or why an apparently healthy tooth may no longer be alive.”

— Dr. Marielaina Perrone, DDS

Can You Have an Infection Without Pain?

Yes.

This surprises many patients.

Once the nerve inside the tooth dies, pain may actually decrease.

Meanwhile, bacteria continue multiplying around the root.

This is why routine dental examinations and X-rays remain so important.

Many root canal infections are discovered before patients realize anything is wrong.

What Causes Root Canal Infections?

Several problems increase the risk.

Deep Tooth Decay

Untreated cavities eventually reach the pulp.

Cracked Teeth

Small fractures allow bacteria to enter the tooth.

Dental Trauma

A sports injury or accident may damage the pulp even if the tooth doesn’t break.

Repeated Dental Procedures

Large fillings or multiple restorations may gradually stress the pulp over time.

Advanced Tooth Wear

Severely worn teeth sometimes expose the pulp to irritation and bacteria.

What Happens If the Infection Is Ignored?

Unfortunately, infections do not disappear on their own.

Without treatment, the infection may lead to:

• Increasing pain
• Bone loss
• Facial swelling
• Dental abscess
• Difficulty chewing
• Tooth loss
• More extensive treatment

Early intervention is almost always preferable to waiting until symptoms become severe.

“Our goal is to preserve natural teeth whenever possible. Delaying treatment often makes that goal much more difficult.”

— Dr. Marielaina Perrone, DDS

How Is a Root Canal Infection Treated?

Treatment depends on the condition of the tooth.

Options may include:

Root Canal Therapy

The infected pulp is removed, the canals are cleaned and disinfected, and the tooth is sealed to prevent reinfection.

Whenever possible, preserving your natural tooth is usually the preferred option.

Dental Crown

Many root canal-treated teeth benefit from a crown to restore strength and protect the remaining tooth structure.

Tooth Extraction

If the tooth cannot be predictably restored because of severe fracture, extensive decay, or insufficient remaining structure, extraction may be recommended.

Replacement options such as dental implants or bridges can then be discussed.

Don’t Ignore the Small Changes

Many patients wait because the discomfort “isn’t that bad.”

Unfortunately, infections often become more complicated with time.

Contact your dentist promptly if you notice:

• Persistent tooth pain
• Swelling
• Lingering temperature sensitivity
• Pain while chewing
• Gum swelling
• Tooth discoloration
• A bad taste or draining bump on the gums

Early evaluation provides the best opportunity to preserve your natural tooth.

The Difference Is Personal

Every root canal infection develops differently.

Some patients experience intense pain.

Others notice only slight sensitivity.

Some have no discomfort at all.

That is why every diagnosis begins with a careful examination rather than assumptions.

At my Henderson practice, I focus on identifying the source of the problem. Not simply treating the symptoms. Through advanced diagnostics, digital imaging, and personalized treatment planning, we can often preserve infected teeth while restoring comfort and function.

Because saving a natural tooth is almost always preferable to replacing one.

Frequently Asked Questions

Does every infected tooth require a root canal?

Not necessarily. The appropriate treatment depends on the health of the pulp, the amount of remaining tooth structure, and whether the tooth can be predictably restored.

Can antibiotics cure a root canal infection?

Antibiotics may help control the spread of infection in certain situations, but they do not remove infected pulp tissue inside the tooth. Definitive dental treatment is usually necessary.

Is root canal treatment painful?

Modern root canal therapy is performed with local anesthesia and is generally no more uncomfortable than receiving a filling. Many patients are surprised by how comfortable the procedure is.

Can a root canal save my tooth?

In many cases, yes. Root canal therapy allows an infected tooth to remain functional for many years when combined with proper restoration and ongoing dental care.

What should I do if my tooth suddenly stops hurting?

Do not assume the problem has resolved. A decrease in pain may indicate that the nerve has died while the infection remains. Schedule a dental examination promptly.

About Marielaina Perrone, DDS

Dr. Marielaina Perrone, DDS, is a trusted cosmetic and family dentist in Henderson, NV, known for helping patients achieve healthy, beautiful smiles through personalized, compassionate care. With more than 20 years of clinical experience, she combines advanced dental expertise with an artistic eye to deliver exceptional results in porcelain veneers, dental implants, smile makeovers, periodontal therapy, Botox, dermal fillers, and facial aesthetic treatments.

A graduate with honors from Stony Brook University School of Dental Medicine, Dr. Perrone remains committed to lifelong learning and regularly pursues advanced continuing education in cosmetic dentistry, implant dentistry, and facial aesthetics. Her comprehensive approach focuses on enhancing oral health, facial harmony, and overall confidence through customized treatment plans tailored to each patient’s unique goals.

Dr. Perrone is passionate about patient education, preventive care, and building lasting relationships founded on trust, communication, and comfort. She believes every patient deserves individualized attention and treatment that supports both long-term health and a confident smile.

Proudly serving Henderson, Green Valley, Las Vegas, Summerlin, and surrounding communities, Dr. Perrone is dedicated to providing modern, patient-centered dentistry in a welcoming environment. Outside the office, she enjoys cooking, staying active, spending time with family, and participating in community activities throughout the Las Vegas Valley.

Reviewed for Clinical Accuracy

This article has been written and clinically reviewed by Marielaina Perrone, DDS, to ensure it reflects current evidence-based dentistry and the personalized philosophy of care practiced at her Henderson, Nevada office.

Last Reviewed: August 2026