Reports & Studies

No-one wants bad breath ...

PD Dr. Kristina Bertl, PhD MSc MBA

Bad breath (halitosis) can be extremely unpleasant for those affected, and it is estimated that approximately one person in four struggles with persistent bad breath. A Belgian study (Quirynen 2009) investigated 2000 patients whose main concern was unpleasant bad breath. The study showed that the oral cavity was the source of bad breath in 75% of patients and thus fell within the dentist’s remit. Only 10% of cases had an extraoral cause, and 15% of participants had what is known as pseudohalitosis, where a patient is convinced they have bad breath even though it can be neither detected nor perceived by other people.

No-one wants bad breath ...

A closer look at the 75% of patients whose bad breath stemmed from the oral cavity reveals the following problematic sites:

  • A tongue coating was the primary aetiological factor in 57% of cases.
  • Gingivitis or periodontitis was the cause in 15% of cases.
  • Gingivitis or periodontitis AND a tongue coating was the cause in 25% of cases.
  • Xerostomia was the suspected cause in 3% of cases. A candida infection, overhanging restorations, or caries were responsible in very few cases.

Bad breath can be treated by mechanically and/or chemically reducing the responsible bacteria and their nutrients and by neutralizing odorous compounds. Unfortunately, not many studies on this subject are available, and the last systematic review (Slot 2015) was unable to deliver clear evidence-based recommendations. In general, however, treatment should be cause-oriented. This means that if the patient has gingivitis or periodontitis, this is what should be treated. If the patient has a tongue coating, they should be told how to clean the back of the tongue. And if the patient’s oral hygiene is inadequate, they should be given appropriate instructions to rectify this. In addition, toothpastes and/or mouth-rinse solutions containing one or a combination of the following ingredients can be used: chlorhexidine, zinc, cetylpyridinium chloride, chlorine dioxide. Possible combination products are (please note that this list is by no means exhaustive):

  • CB12 (0.3% zinc acetate & 0.025% chlorhexidine)
  • Halita mouthwash (0.05% chlorhexidine digluconate, 0.05 % cetylpyridinium chloride & 0.14 % zinc lactate)
  • BreathRX (0.075 % Cetylpyridinium Chloride & Zinc Gluconate)


  1. Slot DE, De Geest S, van der Weijden FA, Quirynen M. Treatment of oral malodour. Medium-term efficacy of mechanical and/or chemical agents: A systematic review. J Clin Periodontol 2015; 42 (Suppl. 16): S303–S316. doi: 10.1111/jcpe.12378. Quirynen M, Dadamio J, Van den Velde S, De Smit M, Dekeyser C, Van Tornout M & Vandekerckhove B. Characteristics of 2000 patients who visited a halitosis clinic. Journal of Periodontology 2009; 36, 970–975.