Halitosis, commonly known as bad breath, affects between 24 and 65% of the population according to epidemiological data. It is not merely a cosmetic problem. For many people, it means social isolation, anxiety about close contact and uncertainty during professional meetings. The good news is that halitosis has a treatable cause in most cases. This article explains where bad breath comes from and how to get rid of it permanently rather than simply masking it.
Research suggests that 80–90% of halitosis cases have an intraoral cause, meaning that the source is directly inside the mouth. The remaining 10–20% originate elsewhere in the body.
Intraoral causes: by far the majority
- Bacterial coating on the tongue. This is the main source of bad breath. Bacteria in the back third of the tongue break down proteins from food and saliva and produce volatile sulphur compounds (VSCs), mainly hydrogen sulphide and methanethiol. These typically smell like rotten eggs or sulphur.
- Periodontitis. Deep pockets around the teeth contain biofilm that produces strong VSCs and other unpleasant-smelling compounds.
- Tartar. Hard deposits hold bacteria close to the gums and cannot be removed with a toothbrush alone.
- Tooth decay. Extensive cavities with dead dental pulp can smell unpleasant.
- Dry mouth (xerostomia). Saliva has an antibacterial function. When saliva production decreases, bacteria multiply more quickly.
- Poorly fitting dental restorations. An inaccurately made or inadequately cleaned restoration traps food debris and biofilm.
Extraoral causes
- Diabetes, which can cause a sweet, acetone-like smell during ketoacidosis
- Liver disease, which can cause a sweet, musky odour
- Kidney disease, which can cause an ammonia-like smell
- Reflux disease and stomach problems
- Chronic sinusitis and tonsillitis
- Certain medicines that reduce saliva production
If you suspect an extraoral cause, consult your GP as well as your dentist.
How can you test your own breath?
You cannot assess your own breath reliably. The brain quickly filters out the smell of your own breath. These practical tests can help:
- The spoon test. Scrape the back third of your tongue with a clean spoon or tongue scraper. Wait a minute, then smell the spoon. If it smells, the source is very likely the tongue, indicating a hygiene-related cause.
- The interdental floss test. Pass floss between your back molars and smell it after removing it. An unpleasant odour suggests plaque in the interdental spaces or periodontitis. If your gums bleed at the same time, book an examination.
- The morning-versus-afternoon test. If the odour appears mainly in the morning and disappears after brushing, it is probably ordinary morning breath, as saliva production decreases overnight. If it persists throughout the day, the underlying problem may be more significant.
- Ask someone close to you. This is probably the most reliable test of all.
What helps with persistent bad breath?
Start with the tongue, not the teeth. The advice to “brush your teeth more often” often does not help because the source is on the tongue.
- Clean your tongue every morning with a tongue scraper or the back of your toothbrush. Move from the back third towards the tip and repeat four to five times. This is one of the most underestimated oral hygiene habits.
- Use interdental brushes every day. With periodontitis, floss alone is not enough.
- Stay hydrated. Drink water regularly and chew xylitol gum between meals. Stimulating saliva supports the mouth’s natural self-cleaning ability.
- Avoid long-term use of alcohol-based mouthwashes, which dry out the mucous membranes, as well as masking sprays that only cover the odour.
- Limit onions, garlic, large amounts of coffee and alcohol. These can increase the production of volatile sulphur compounds.
- Mouthwashes with active ingredients can help: chlorhexidine for short-term use, or cetylpyridinium chloride and zinc ions for other situations. They do not replace mechanical cleaning.
You can find detailed instructions for daily care in our complete guide to dental hygiene.
When should you see a dentist or hygienist?
If the odour has not disappeared after four weeks of consistent home care, or if it is getting worse, it is time for a check-up. The cause may be hidden in deep periodontal pockets, tartar below the gum line or cavities between the teeth.
At m2stoma Brno, our approach includes:
- A comprehensive examination of the gums, pocket depths, tartar and cavities
- Professional dental hygiene with Airflow and erythritol powder. The 14 μm particles are gentle on the gums while removing biofilm, making this one of the more advanced hygiene treatments with a measurable effect on halitosis.
- The GBT protocol (Guided Biofilm Therapy) as a structured treatment approach
- SRP (scaling and root planing), meaning deep cleaning of the root surfaces, when periodontitis is present
- An individual recall plan every 3–6 months to maintain the result
Fifteen years of practice have shown us that combining professional treatment with consistent home care resolves most intraoral causes of halitosis.
Frequently Asked Questions
How can I test whether I have halitosis?
Scrape the back of your tongue with a clean spoon, wait a minute and smell the spoon. If you notice an odour, you may have bad breath. Honest feedback from someone close to you is more reliable, however.
Can mouthwash get rid of persistent bad breath?
It can help in the short term, but not in the long term. Mouthwashes with active ingredients such as cetylpyridinium chloride or zinc can be useful, but without tongue cleaning and professional dental hygiene they will not solve the problem. Masking sprays are not enough on their own.
Is bad breath connected to the stomach?
Less often than people commonly assume. Approximately 10–20% of cases have an extraoral cause, and only a minority of those are linked to the stomach, for example reflux. In many patients who go straight to an internal medicine specialist because of bad breath, the cause eventually turns out to be treatable and located in the mouth.
Conclusion
In the vast majority of cases, bad breath has a treatable cause in the mouth itself, primarily on the tongue and around the gums. If you see no improvement after a month of home care, book an appointment for a professional examination and Airflow hygiene at m2stoma Brno. We will create an individual care plan that addresses the cause of halitosis rather than merely masking it.