Bad Breath: Causes, Treatments and At-Home Tips

Bad breath, or halitosis, is something most of us experience from time to time. However, when it’s persistent, it can start to feel uncomfortable – whether it’s a strong taste in your mouth that doesn’t go away, a comment from someone else, or just a sense that something’s not quite right, ongoing bad breath is often a sign that something in the mouth or digestive system needs attention.

The good news is that most causes of bad breath are treatable. In many cases, it’s linked to bacteria in the mouth, plaque build-up, or food particles that have been missed during brushing. Sometimes, it can be a sign of dry mouth, gum disease, or even an issue elsewhere in the body.

If you’ve been noticing that your breath doesn’t stay fresh, no matter how much you brush, chew gum, or rinse, it’s worth speaking to your dentist.

At Oasis Dental Studio in the Gold Coast, Brisbane and Pottsville, we can help to identify bad breath causes and work with you on a plan to treat the issue.

What Causes Bad Breath?

There are a few different possible bad breath causes. It often depends on what’s going on in your mouth, how thoroughly you’re cleaning your teeth, and whether there are any underlying dental or medical issues.

The most common cause is the buildup of bacteria in the mouth. These bacteria feed on leftover food particles, especially proteins, and produce sulphur-containing gases as a byproduct. These gases are what give bad breath that distinctive smell and taste, sometimes described as metallic.

Bad breath can also be caused or worsened by plaque and tartar. If plaque is left on the teeth for too long, it can harden into tartar, which traps more bacteria and contributes to gum inflammation and odour.

Another possible cause can be gum disease. When the gums become inflamed or infected (known as gingivitis or periodontitis), they can begin to pull away from the teeth. This creates pockets where bacteria collect, and the resulting odour from the bacteria can lead to persistent bad breath.

Dry mouth can be another cause. Saliva helps to wash away bacteria and neutralise acids. If your mouth is dry, whether from dehydration, certain medications, or mouth breathing, odour-causing bacteria can be more present.

Smoking and tobacco use can also contribute to persistent bad breath. Smoking contributes to dry mouth, slows healing, and adds its own distinct smell to the breath. It can also make gum disease more likely, which further affects breath.

Occasionally, bad breath can be related to issues outside the mouth, such as reflux, sinus infections, diabetes, or even liver or kidney conditions. If your dentist rules out oral causes and the problem persists, a referral to your GP may be helpful, as bad breath treatment alone may not target the underlying cause.

Is Bad Breath Always Caused by Poor Hygiene?

Bad breath is not always simply caused by poor oral hygiene, however, oral hygiene does influence how fresh your breath stays throughout the day. Even if you’re brushing twice daily, certain areas (like the back of the tongue, around old fillings, or between teeth) can easily be missed.

If flossing isn’t part of your daily routine, bacteria and food debris can stay trapped between teeth, which creates a hidden source of odour over time. Likewise, if you wear dentures or dental appliances and they’re not cleaned properly, bacteria and fungi can build up there, as well.

Some people are more prone to bad breath because of reduced saliva or medication side effects, so it’s not always about hygiene alone. However, a thorough dental clean and tailored advice can often make a noticeable difference.

How Do You Know if You Have Bad Breath?

Some signs that may indicate ongoing bad breath include:

A persistent bad taste in your mouth
Noticing that your breath doesn’t feel fresh shortly after brushing
Avoiding close conversations or feeling self-conscious
Seeing a white or coated layer on your tongue
Bleeding gums or ongoing dryness

If you’re not sure, a trusted partner or friend may be able to help you check. However, your dentist can also help. At Oasis, we can check for signs of inflammation, plaque, or other issues that may be contributing and let you know if any concerns are present.

Causes of Persistent Bad Breath

When bad breath doesn’t go away, even after brushing, flossing, or using mouthwash, it can be due to an issue inside the mouth that needs more than a surface-level clean.

Some of the most common dental causes include:

Gum disease (gingivitis or periodontitis)
Inflamed gums, whether from mild gingivitis or more advanced periodontitis, can create deep pockets between teeth and gums where bacteria can be hard to remove. These bacteria releases odours, and unless the condition is treated, the odour usually persists.
Plaque and calculus build-up
Plaque can trap food and bacteria, especially around the gums and between teeth. Once plaque hardens into calculus (tartar), it can’t be removed with regular brushing and will require a professional clean.
Bacteria on the tongue
The tongue, especially towards the back, is often missed during brushing. Bacteria and dead cells can build up on the tongue, which can cause an odour. Using a tongue scraper or brushing your tongue gently can help.
Decaying teeth or broken fillings
Tooth decay and older fillings that are no longer sealed properly can trap food particles or allow bacteria to reach the softer layers of the tooth. This can lead to strong odours, even if you aren’t experiencing tooth pain.
Dry mouth
Without enough saliva to keep the mouth clean, bacteria can multiply faster, and bad breath often follows. If you’re waking up with a dry mouth, breathing through your mouth overnight, or taking medication that reduces saliva, this could be contributing to persistent bad breath.

When to See a Dentist

If you’ve tried improving your oral hygiene and your breath still doesn’t feel fresh, or if you’re experiencing bleeding gums, a persistent bad taste, or a coated tongue, we recommend seeing a dentist for advice on bad breath treatment or to assess the possible causes.

You should also contact us if:

Your bad breath has been present for more than a few weeks
You notice sores, swelling, or changes in your mouth
You’re waking up with a dry mouth every day
You have gum sensitivity or teeth that feel loose
You’ve had recent dental work that doesn’t feel quite right

At Oasis Dental Studio in the Gold Coast, Brisbane and Pottsville, our dentists can assess your oral health and recommend any treatments or further assessments that may be necessary.

How We Can Treat Bad Breath

If bad breath is an ongoing issue, one of our dentists can conduct a thorough check-up, professionally clean your teeth, and help identify whether the problem is oral or something that needs to be assessed further.

Your dental check-up at Oasis may include:

A full oral exam to check for gum disease, decay, or infections
A scale and clean to remove plaque and tartar
A discussion of your brushing and flossing technique
Advice on cleaning your tongue and using the right toothpaste
Identifying any dry mouth issues
Discussing diet or lifestyle factors that may be contributing

If any dental-specific causes are ruled out and bad breath still remains present, we may refer you to your GP or a specialist to assess if there are any medical causes, such as reflux, sinus infections, or health conditions.

At-Home Tips for Fresher Breath

For at-home bad breath treatment, simply making improvements to your oral hygiene routine can help, especially if the bad breath is related to a build up of plaque or bacteria, or a dry mouth.

There are also some general health and cleaning steps to follow that can help you to get rid of and prevent bad breath.

Brush your teeth twice a day
Use a soft toothbrush and fluoride toothpaste to brush your teeth for two full minutes, morning and night. Electric toothbrushes can help you clean your teeth better, but they aren’t necessarily a must-have.
Make sure to brush or scrape your tongue
Since bad breath can actually come from the tongue, you should also gently brush your tongue or use a tongue scraper daily to remove the coating that often traps odour.
Floss daily
Flossing removes debris from between your teeth where your brush can’t reach. It’s especially helpful for reducing bacteria in the areas that tend to contribute most to bad breath.
Stay hydrated
Drink plenty of water throughout the day to support saliva flow. If your mouth often feels dry, chewing sugar-free gum may also help.
Rinse your mouth after consuming odour-heavy foods or drinks
Garlic, onion, coffee and alcohol can all contribute to stronger breath, and while these smells are temporary, rinsing with water or chewing sugar-free gum afterwards can help.
Avoid smoking
Quitting smoking or tobacco products not only improves your breath, but also helps prevent gum disease and dry mouth over time.
Clean your dental appliances regularly and thoroughly
If you wear dentures, a mouthguard, or any other removable dental appliance, make sure that you clean it daily using the correct method. Bacteria and fungi can collect on these surfaces and worsen breath if they are not cleaned properly.

Bad Breath