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What are the Signs of an Infected Tooth?

Toothaches can range from mildly uncomfortable to excruciatingly painful, and one of the common underlying causes is a tooth infection. Recognizing the signs of an infected tooth is essential because prompt treatment is necessary to prevent complications and preserve your oral health. 

In this comprehensive guide, we will explore the signs and symptoms of an infected tooth, its causes, and why early detection and treatment are crucial.

A tooth infection, also known as a dental abscess or tooth abscess, occurs when bacteria invade the pulp, which is the innermost part of the tooth. This infection can be extremely painful and should not be ignored. Here are the key signs to watch out for:

Signs and Symptoms of an Infected Tooth

An infected tooth, also known as a dental abscess or tooth abscess, can cause a range of signs and symptoms that should not be ignored. Recognizing these signs early is crucial for seeking prompt dental care to prevent the infection from worsening. Here are the common signs and symptoms of an infected tooth:

1. Severe Toothache: 

One of the most prominent symptoms of a dental abscess is a severe and persistent toothache. The pain can be sharp, throbbing, or constant and often worsens when you chew, bite, or apply pressure to the affected tooth.

2. Sensitivity to Temperature: 

Infected teeth are often sensitive to hot and cold temperatures. You may experience a sharp, shooting pain when consuming hot or cold foods and beverages.

3. Swelling: 

Dental abscesses can lead to localized swelling in the affected area. Swelling may be visible on the face or cheek near the infected tooth. It can range from mild puffiness to significant swelling.

4. Fever: 

In some cases, an infected tooth can lead to a low-grade fever as your body’s immune system responds to the infection.

5. Bad Taste or Smell: 

An unpleasant taste or odor in your mouth can be a sign of a dental abscess. This may result from the presence of pus associated with the infection.

6. Pimple-Like Bump on Gums: 

In some cases, a dental abscess may cause the formation of a pimple-like bump (dental abscess or gum boil) on the gum near the infected tooth. This bump may release pus when pressure is applied.

7. Difficulty Opening Your Mouth: 

Severe dental abscesses can lead to difficulty in fully opening your mouth. This limitation in jaw movement can be painful and affect your ability to eat and speak.

8. General Malaise: 

An infected tooth can make you feel generally unwell. You may experience fatigue, weakness, and a sense of being under the weather.

Causes of Tooth Infections 

Tooth infections, also known as dental abscesses or tooth abscesses, typically occur when bacteria invade the pulp of a tooth, leading to infection and the formation of a pocket of pus. Several common causes and contributing factors can lead to tooth infections:

1. Untreated Cavities: 

One of the most common causes of tooth infections is untreated cavities (dental caries). Cavities form when bacteria in the mouth produce acids that erode the tooth enamel. Over time, these acids create small openings or holes in the tooth, providing a pathway for bacteria to enter the pulp.

2. Cracked or Fractured Teeth: 

Teeth that are cracked or fractured can allow bacteria to penetrate the inner layers of the tooth. Even hairline cracks can provide a route for infection to reach the pulp.

3. Gum Disease: 

Advanced gum disease (periodontitis) can lead to the formation of pockets or gaps between the gums and teeth. These spaces can harbor bacteria, which can then migrate into the roots and pulp of the teeth, causing infection.

4. Dental Trauma or Injury: 

A significant impact or trauma to a tooth, such as a sports injury or accident, can damage the tooth’s structure, expose the pulp, and create an entry point for bacteria. This can lead to an infection over time.

5. Inadequate Dental Procedures: 

In some cases, dental procedures that do not completely remove all infected or damaged tissue can leave behind residual bacteria, which can lead to a secondary infection.

6. Weakened Immune System: 

A compromised immune system, whether due to a medical condition or certain medications, can make it more challenging for the body to fend off bacterial infections, increasing the risk of dental abscesses.

Potential Complications of an Infected Tooth

1. Severe Pain: 

Dental abscesses can cause excruciating pain that can radiate to the jaw, ear, and neck. The pain can be so intense that it interferes with daily activities like eating and sleeping.

2. Swelling: 

An abscess often results in localized swelling in the affected area. In some cases, the swelling can extend to the face, cheek, or neck, causing visible discomfort and distortion of facial features.

3. Fever: 

As the body tries to fight off the infection, a fever may develop. This is a systemic response to the presence of bacteria and toxins in the bloodstream.

4. Difficulty Swallowing or Breathing: 

In severe cases, a dental abscess can lead to difficulty swallowing or breathing. This occurs when the swelling puts pressure on the throat or airway, potentially causing a medical emergency.

5. Abscess Drainage: 

If the dental abscess ruptures on its own, it can lead to drainage of pus into the mouth. This can result in a foul taste and odor, which is often accompanied by temporary relief from pain. However, the infection will persist until treated by a dentist.

6. Spread of Infection: 

If left untreated, a dental abscess can spread to surrounding tissues and even adjacent teeth. The infection can enter the bloodstream, potentially leading to a condition known as sepsis, which is life-threatening.

7. Dental Cysts and Granulomas: 

Chronic dental abscesses can lead to the formation of dental cysts or granulomas. These are pockets of tissue or fluid that can develop within the jawbone, causing further complications.

8. Tooth Loss: 

In some cases, an infected tooth may become so damaged that it cannot be saved and must be extracted. Losing a tooth can have significant consequences for oral function and appearance.

9. Systemic Health Issues: 

There is evidence to suggest a link between untreated dental infections, such as abscesses, and systemic health issues like cardiovascular disease, diabetes, and respiratory problems. The bacteria from the infection can enter the bloodstream and affect other parts of the body.


Recognizing the signs of an infected tooth is crucial for your oral health and overall well-being. If you experience a severe toothache, sensitivity to temperature, facial swelling, fever, bad taste or smell, or any other concerning symptoms, it’s essential to seek prompt dental care. Tooth infections can lead to serious complications if left untreated. Early detection and treatment by a dental professional are essential to alleviate pain, prevent further damage, and preserve your smile. Don’t ignore the signs; prioritize your oral health.