Dr. Shilpy Bhandari 31 Aug 2021

Bad breath or oral malodor is an unpleasant smell emitted from the mouth. This is experienced by up to 50% of people globally. Bad breath may lead to lower self-confidence and social embarrassment. Affected individuals tend to isolate themselves, which impacts their psychological health. With increase in social awareness, individuals seek medical guidance and ways to manage bad breath. In this article, we discuss causes, diagnosis, and management of bad breath.

Who can develop bad breath?

Bad breath affects all age groups.

What are the causes of bad breath?

About 85% of bad breath originates from the oral cavity. This is due to high bacterial activity. Specific bacteria in the mouth break down food particles that are accumulated around teeth and gums. The breakdown releases volatile sulfur compounds (e.g., hydrogen sulfide, methyl mercaptan, and dimethyl sulfide) that cause bad breath. The coating on the tongue’s surface also promotes bacterial growth and prevents the cleansing action of saliva. This further contributes to bad breath.

Other causes of bad breath include:

  • Foods and drinks: Habits such as smoking, chewing betel nut, and consuming alcohol, and intake of volatile foods such as onion, garlic, spices, pickles, and radishes results in bad breath. These foods have a high concentration of sulfur which, on degradation in the gastrointestinal tract, releases a distinctive odor. The odor may remain for a few hours after the food’s consumption.
  • Gum diseases: Poor oral hygiene encourages the growth of bacteria in the oral cavity. This results in gum diseases such as gingivitis and periodontitis (infection of gums and tooth-supporting structures). Bacteria-causing gum diseases degrade the food debris and release volatile sulfur compounds, creating bad breath.
  • Dental issues: Tooth decay, improper fillings, unclean dentures, or inappropriate crowns and bridges may become sites for accumulation of food. These sites have high bacterial activity causing bad breath.
  • Dry mouth: Dry mouth is caused by excess caffeine intake, tobacco use, intake of medications, salivary gland diseases, or other medical conditions. Saliva cleanses the accumulated food debris in the mouth. Chemicals present in the saliva help break down the food in the mouth and prevent cavities and infections. Reduced salivary flow hampers the cleansing action and encourages bacterial activity on accumulated food debris.
  • Nose, sinus, or throat infections: The presence of nose, sinus, or throat infections causes postnasal drip (accumulated mucus running into the throat from the nose). High bacterial activity in the accumulated mucus produces bad odor. When the smelly mucus seeps into the throat, it combines with the exhaled air and transfers the odor to the breath.
  • Systemic diseases: The presence of conditions such as diabetes, liver disease, kidney disease, gastric reflux, or cancers lead to bad breath.
  • Psychogenic malodor: This is psychological condition where a patient complains of continuous bad breath even when it is not there. The patient continues to complain about bad breath even after the treatment. Such malodors cannot be identified objectively.

How is bad breath diagnosed?

Bad breath can be easily assessed by individuals. In some instances, a dentist can help diagnose malodor. Some other methods to diagnose bad breath clinically are:

  • Organoleptic assessment: In this subjective assessment, the examiner assesses the breath of the patient from a distance of 1.5m from the mouth. Scores are assigned based on the severity of odor. The grade 0 stands for no malodor and 4 stands for very severe oral malodor.
  • Halimeter test: In this test, a sensor is placed close to the patient’s mouth. The device senses volatile sulfur compounds and gives the measurement of foul-smelling compounds in parts-per-billion (ppb). Exhaled air with 300-400 ppb of volatile sulfur compounds signifies the presence of malodor.
  • Gas chromatography: The test helps determine different components of oral malodor. The results are obtained from a computer-based database.

How is bad breath managed?

Patients who complain of bad breath should undergo a complete oral examination. A thorough examination will help the dentist identify the cause of malodor. In case of extraoral causes, patients are referred to a physician for further examination. Patients with psychogenic malodor are referred to a psychiatrist for necessary intervention. Patients with gum diseases are advised to undergo gum surgery.

Here are some easy recommendations to manage bad breath:

  • Brush and floss twice daily to remove trapped food debris. 
  • Use a tongue scraper after brushing teeth.
  • Use an antimicrobial toothpaste containing triclosan or stannous-containing sodium fluoride. They help control bad breath for 12 hours after brushing.
  • Use mouthwashes containing chlorhexidine, cetylpyridinium chloride, or triclosan. They help reduce bad breath. However, these mouthwashes should be used only for the prescribed duration.
  • Use chewing gums and oral deodorants to reduce bad breath and stimulate salivation. 
  • Eat natural ingredients such as cloves, parsley, mint, or fennel seeds to temporarily mask the malodor.
  • Reduce the intake of volatile foods such as onion, garlic, cabbage, radish, and cauliflower.
  • Avoid smoking and intake of alcohol.
  • Drink a lot of water to avoid drying of mouth.
  • Regularly eat a balanced diet along with fibrous fruits.
  • Visit a dentist regularly for professional cleaning of teeth.

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About the Author:
Dr. Shilpy Bhandari is an experienced dental surgeon, with specialization in periodontics and implantology. She received her graduate and postgraduate education from Rajiv Gandhi University of Health Sciences in India. Besides her private practice, she enjoys writing on medical topics. She is also interested in evidence-based academic writing and has published several articles in international journals.


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