<strong>HALITOSIS</strong> <br>Bad breath problems
Bad breath problems

Halitosis, known to most as bad breath, is a set of unpleasant odours that are emitted through the mouth. It is a problem that affects one out of every two people.

It is considered a social problem and is associated with deficient oral hygiene or with oral-related diseases, although it can sometimes be a result of some other disease.


Depending on its origin, there are two types of Halitosis: Oral Halitosis and Extraoral Halitosis.

Oral Halitosis comes from the oral cavity itself and is due primarily (41%) to the accumulation of oral biofilm (bacterial plaque) on the tongue. Although it can also be caused by other situations such as: periodontal problems, dental caries, and smoking, among others. According to several scientific studies, Oral Halitosis is responsible for 90% of all cases.

When halitosis originates outside of the oral cavity, it is known as Extraoral Halitosis. It is due primarily to systemic conditions of the upper/lower respiratory tract, the digestive system, as well as liver or kidney diseases. And this corresponds to 10% of all cases.


The production of malodorous substances, most frequently Volatile Sulphur Compounds (VSC), is associated with degradation products from the metabolism of the bacteria, usually gram-negative anaerobic bacteria, which are mainly located in the posterior dorsum of the tongue and in other locations such as periodontal pockets.

The causes of Oral Halitosis can be either pathological or non-pathological.

The non-pathological causes include:

  • Morning breath: during sleep saliva flow diminishes, favouring the uncontrolled growth of malodorous gas-producing bacteria.
  • Age: the quality of breath changes with age. It is likely that the elderly suffer regressive changes in the salivary glands affecting the quality and quantity of saliva, even when oral hygiene is optimal.
  • Dentures: dentures and bridges can collect food debris. If left overnight, they produce a characteristic unpleasant odour.
  • Medicines: some medicines cause xerostomia (dry mouth), such as anticholinergics, antidepressants, etc. Saliva promotes cleaning of the oral cavity and reduces odour.
  • Smoking: smoking causes a distinctive breath that can last several days, even after having stopped smoking.
  • Fasting periods: skipping meals and following a hypocaloric diet can promote bad breath.
  • Diet: after the intake of certain foods (onion, garlic) or consuming alcohol, certain metabolites can be gastrointestinally absorbed, go into the blood stream, and be metabolised in the mucosa and liver and then expelled by the lungs.

Pathological Causes:

  • Periodontal disease, caries.
  • Poor Oral Hygiene, failure to remove oral biofilm (bacterial plaque), causes bacterial growth. Bacteria tend to accumulate on the tongue, in interproximal spaces, subgingival areas, abscesses. The tongue is the place in the oral cavity where most anaerobic bacteria reside.
  • Ulcerative Causes: traumatic, infectious ulcers, stomatitis.
  • Pharynx: viral, bacterial or fungal infections.
  • Necrosis from radiotherapy and chemotherapy in patients with malignancies.

The causes of Extraoral Halitosis may include: nasal problems (sinusitis), digestive diseases, respiratory diseases, systemic diseases (uncontrolled diabetes mellitus, kidney infection, liver dysfunction, Sjögren’s Syndrome, rheumatoid arthritis, etc.).


  • Fermandez Aménaza J., Rosales Gonzales R. Halitosis: Diagnóstico y tratamiento en atención primaria. MEDIFAM 2002; 12:46-57. Vol. 12-Num.1.
  • Mc Dowell JD, Kassebaum DK, Diagnosing and treating halitosis. J Am Dent Assoc 1993; 124: 55-64.
  • Winkel EG, Roldán S, Van Winkelhoff AJ, Herrera D, Sanz M. Clinical effects of a new mouthrinse containing chlorhexidine, cetylpyridinium chloride and zinc-lactate on oral halitosis. A dual-center, double-blind placebo-controlled study. J Clin Periodontol. 2003 Apr;30(4):300-6.
  • Roldán S, Herrera D, Sanz M.Biofilms and the tongue: therapeutical approaches for the control of halitosis. Clin Oral Investig. 2003 Dec;7(4):189-97. Epub 2003 Sep 26.



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