Around 90% of bad breath originates in the mouth — coating on the tongue, dental calculus, gum inflammation and cavities. Cleaning the tongue, having a scaling appointment and filling any cavities resolves it in most cases. Mouthwash only masks the smell temporarily.
The cause is almost always in the mouth
Many people assume bad breath comes from the stomach. In fact, 85–90% of cases originate in the mouth. The smell is produced by bacteria breaking down food debris and dead cells into sulphur compounds.
Causes inside the mouth
- Coating on the tongue: the single biggest cause. Bacteria collect in the rough surface at the back of the tongue.
- Calculus and gum inflammation: hardened deposits shelter bacteria.
- Cavities: food packs into them and decomposes.
- Dry mouth: saliva keeps the mouth clean. Drinking too little, breathing through the mouth, or certain medications dry it out — which is why breath is worst on waking.
- Infection around a wisdom tooth: food traps there and is hard to clean.
- Smoking and paan: they smell in themselves and also dry the mouth.
Causes outside the mouth
The remaining 10–15% can be sinus infection, tonsil stones, uncontrolled diabetes, or certain digestive problems. These are worth investigating only once the teeth and gums have been confirmed healthy and the smell persists.
What actually works
- Clean your tongue: every morning, draw a tongue cleaner from back to front three or four times. For many people this alone makes a dramatic difference.
- Have a scaling appointment: brushing does nothing to hardened calculus. Scaling costs ৳1,000–2,000.
- Fill any cavities: the smell won't go while decay remains — see fillings.
- Floss once a day: trapped food between teeth is a very common source.
- Drink more water: a dry mouth smells worse.
- Sugar-free gum: stimulates saliva and helps temporarily.
The truth about mouthwash
Mouthwash masks odour for a while; it doesn’t treat the cause. Alcohol-based mouthwash used long-term dries the mouth further, which ultimately makes breath worse. If you use one, choose alcohol-free, and treat it as an addition to brushing and flossing rather than a replacement.
It’s hard to judge your own breath. Ask someone close to you directly, or lick the back of your wrist, let it dry for ten seconds and smell it — that’s reasonably reliable.
Book an appointment
Don't wait out a toothache
Home measures may dull the pain, but the cause stays. Our dentists sit daily from 4:00 PM to 9:00 PM in Mirpur 12.
Related services
FAQ
Related questions
Usually one of two reasons — the tongue isn’t being cleaned, or there is hardened calculus that brushing cannot remove. Start cleaning your tongue and book a scaling appointment.
It masks it temporarily while the cause remains. Alcohol-based mouthwash used long-term can dry the mouth and make the problem worse.
Saliva production drops during sleep, so the mouth dries and bacteria multiply. This is normal and clears after brushing and cleaning the tongue. Breath that smells all day is not normal.
Read next
More articles
- Dental care
Home Remedies for Toothache — What Works and What Doesn't
What actually helps until you can see a dentist — and which popular home remedies do real harm.
- 18 August 2026
- 6 min read
- Gum health
Why Your Gums Bleed — Causes and What to Do
Blood every time you brush? It isn’t normal — but in most cases it’s straightforward to fix.
- 5 August 2026
- 5 min read
Book an appointment
Don't let a small problem get expensive
Treated early, most dental problems cost less and hurt less. Call us today — we’re open daily from 4:00 PM to 9:00 PM.