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Can Cavities Cause Bad Breath: 9 Of The Worst Causes

Las Caries Pueden Causar Mal Aliento || Can Cavities Cause Bad Breath

Dr. Andreas

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Written by

Q.F. Nayibe Cubillos Morales


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Dr. Gustavo Assatourians D.D.S

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Can Cavities Cause Bad Breath?

In our current era, marked by the frequent use of masks due to public health requirements, many have discovered a previously unnoticed problem: bad breath. This condition, which could have been present even before the pandemic, has become more evident with the constant use of masks. The phenomenon has caused an increase in awareness about oral health, leading many to wonder if problems such as cavities may be behind unpleasant mouth odor.


Causes of Bad Breath

Causas del Mal Aliento

Bad breath, also known as halitosis, can be caused by various causes beyond poor oral hygiene. It has multiple origins, with the accumulation of bacteria in the mouth being one of the most common. This problem can arise from various causes related to oral and gastrointestinal health. These include:

● Dry mouth: Saliva plays a key role in oral cleanliness, so a deficiency can cause bad breath. Factors such as smoking, certain medications, and illnesses can reduce saliva production.

● Head and neck cancers: Some signs of these cancers include sores that do not heal, mouth pain, difficulty swallowing, lumps in the neck, and unexplained weight loss.

● Gastroesophageal Reflux Disease (GERD): With this condition, stomach acid returns to the esophagus, which can cause bad breath.

● Tonsil stones: Food remains can accumulate in the tonsils and solidify, forming stones that emit a bad odor.

● Gum disease: Gingivitis and periodontitis are inflammations of the gums caused by plaque buildup. They can cause redness, swelling, bleeding, and, in advanced cases, tooth loss.

● Respiratory infections: Conditions such as pneumonia can cause foul-smelling expectoration.

● Diabetes: This disease increases the risk of gum disease, which can contribute to bad breath.

 Liver and kidney diseases: These disorders affect the body’s ability to filter and eliminate toxins, which can result in halitosis.

● Sjögren’s Syndrome: This autoimmune disease can cause dry mouth and other symptoms, contributing to bad breath.

If bad breath persists despite good oral hygiene and cavity treatment, it is important to consider other possible causes. Among them, dietary factors such as the consumption of certain foods (garlic, onion), smoking, alcohol, diabetes complications, acid reflux, allergies, sinusitis, and the use of orthodontic devices or dentures can be decisive. A comprehensive evaluation by a healthcare professional is key to identifying and treating the underlying cause of bad breath.


Cavities and Bad Breath

caries y mal aliento

A cavity can indirectly contribute to bad breath. You may also experience a sour or bitter taste in your mouth that doesn’t seem to go away with brushing. This happens to people of all ages, including children.

Also known as tooth decay, a cavity is a small hole that forms in your tooth due to the breakdown of enamel. It occurs when sticky bacteria called plaque builds up on your tooth. Foods or drinks rich in starch and sugar can feed these bacteria, which then produce acids that destroy tooth enamel.

While not all oral bacteria are harmful, some give off a bad taste or odor. This may be the case with the bacteria-causing plaque associated with cavities. Instead of the cavity itself having a bad odor, it’s more likely that you’re smelling the underlying bacteria.

Additionally, according to a 2021 review, bacteria buildup on the tongue is another common cause of bad breath. This biofilm may consist of the same odor-causing plaque that contributes to cavities.


What other Signs and Symptoms Occur with a Cavity?

In addition to bad breath, several signs may indicate the presence of a cavity. Cavities do not usually cause symptoms in their initial stages, but as tooth decay progresses, they can manifest in a variety of ways:

● Toothache

● White or dark spots on your teeth

● Sensitivity to hot or cold foods or drinks

● Abscess around the affected tooth

● Signs of an infected abscess, such as fever or facial swelling

● These symptoms, along with bad breath, indicate that you may be experiencing tooth decay. It is important to pay attention to these signs and seek dental care to prevent further complications.


Importance of Tooth Brushing

importancia del cepillado dental

Dental plaque, in a favorable environment, damages the structure of teeth and can lead to cavities. It is crucial to eliminate it in time through proper tooth brushing. Cleaning should include not only the teeth, but also the gums, tongue, cheek,s and, to some extent, the throat. The use of mouthwashes also contributes to comprehensive oral hygiene.


When Brushing is not Enough

If, despite regular brushing and the use of mouthwash, bad breath persists, there may be deeper problems such as advanced cavities, tartar, or gum disease. These problems require more specialized attention. Living with bad breath can be challenging for both the affected person and those around them. It is important not to mask the problem with temporary solutions such as oral sprays. Instead, it is best to seek professional help to address the underlying cause.



In conclusion, bad breath, or halitosis, is a complex condition with multiple potential causes beyond poor oral hygiene. Conditions such as dry mouth, gastrointestinal diseases such as GERD, respiratory infections, liver and kidney diseases, and autoimmune disorders such as Sjögren’s Syndrome may be contributing factors. Additionally, dental conditions such as gingivitis, tonsil stones, and cavities are also common causes of bad breath.

It is essential to recognize that a comprehensive approach is necessary to effectively treat bad breath. This includes not only maintaining good oral hygiene but also considering and treating underlying medical conditions. The persistence of symptoms despite adequate oral care should motivate consultation with health professionals for appropriate diagnosis and treatment. Thus, a problem that significantly impacts quality of life and social interactions can be effectively addressed.

Frequently Asked Questions

It is important to remember that a cavity per se has no odor. If you experience bad breath associated with a cavity, you are probably smelling bacteria from plaque buildup. Based on shared experiences, this smell is often described as similar to sulfur.

The only way to eliminate bad breath caused by cavities is through the appropriate dental treatment. The dentist will eliminate harmful bacteria affecting your tooth and refill the tooth to prevent further decay.

When a cavity reaches a stage where holes begin to form, food particles can become trapped. These particles sometimes remain inside the cavity for weeks. As a result, the person’s breath takes on an odor that resembles that of spoiled food.

If bad breath is caused by an infection or is a side effect of a specific medication, consulting your doctor or dentist will help to eliminate it permanently. However, in most cases, bad breath is not solved with a single intervention.



1. Healthdirect. (May, 2022). Halitosis (bad breath).

2. Babcock P. (Agu, 2015). Change Your Breath From Bad to Good. WebMD.

3. Mayo Clinic. (Dec, 2023). Bad breath.

4. Cleveland Clinic. (Jul, 22). Bad Breath (Halitosis).

5. Cherney K. (May, 2023). Can Bad Breath Be a Sign that You Have a Cavity?. Healthline.

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