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A Fresh Start: We Look Into Causes of Bad Breath

It is important to get bad breath under control because it affects one's confidence and self esteem. Bad breath odor can also have a significant impact on relationships with others, as it can make people feel embarrassed and uncomfortable in many social situations.

Additionally, bad breath is often caused by underlying oral health issues like gum disease or tooth decay, which can lead to more serious problems if not addressed properly.

Therefore, it is important to take steps towards treating your bad breath so that you can continue living life without worrying about the negative effects of halitosis.

What is Bad Breath?

Bad breath originates from** 5 sources** in one’s mouth:

  • Teeth – Do you have any dental decay or any form of infection?
  • Gums – Have you recently had a clean of your teeth/gum within 6 months? Bacteria will accumulate around your gums like weed in your garden.
  • **Throat **– Bacteria will accumulate around the area over time like a shower drain
  • Tongue – Like dirt on a carpet
  • Medical Conditions – Common medical issues such as a upset stomach or other gastrointestinal issues

Bad breath is also known as halitosis.

Saliva Production

The role of saliva is to cleanse your mouth and rebalance its environment and help remove particles.

Decreased saliva production - also known as dry mouth symptoms

Saliva helps cleanse your mouth, removing particles that cause bad odors. A condition called dry mouth or xerostomia (zeer–o-STOE-me-uh) can contribute to bad breath because production of saliva is decreased. Dry mouth naturally occurs during sleep, leading to "morning breath," and it worsens if you sleep with your mouth open. Chronic dry mouth can be caused by a problem with your salivary glands and some diseases.

Gum disease

Gum disease occurs when bacteria build up on teeth around the gums and irritate or infect the gum tissue.

In the early stage of gingivitis, symptoms may include red, swollen, or bleeding gums. If there is also bad breath or a bad taste in the mouth, gingivitis may have progressed to a more severe form called periodontitis. This is a dental concern that requires continuous gum care from a dentist.

It is often caused by an excessive and hardened build-up of plaque, and bacteria on the teeth and gums. Plaque build-up on teeth is natural and can be cleaned through brushing, flossing and professional cleaning (scale and clean) by a dentist. When it becomes excessive on the teeth and gum lines, however, this bacteria can be damaging and lead to issues like tooth decay, infection and gum disease.

https://dazzlingsmilesdental.com.au/why-does-gum-disease-cause-bad-breath/

Bad breath odours

Excessive bacteria in the small intestine can cause extreme amounts of rotten-smelling gas and belching, causing your breath to have an unpleasant smell. This condition is referred to as small intestinal bacterial overgrowth (SIBO).

If bad breath is a problem, see your dentist who can check your mouth for common causes of halitosis, advise you about oral hygiene, and if necessary, refer you to your doctor.

Bad breath bacteria

Bad breath is often caused by bacteria on the surfaces of the tongue and throat. Certain types of foods, particularly those with high protein content like meat and dairy, can lead to the rapid breakdown of these bacteria, resulting in the release of volatile sulphur compounds (VSC) that cause a sulphurous odor when you exhale.

Morning Breath

Bad breath when you wake up is normal. It will go away after eating, drinking and cleaning teeth.

If bad breath continues throughout the day, it may be a sign of a dental or other health condition.

If bad breath is a problem, see your dentist who can check your mouth for common causes of halitosis, advise you about oral hygiene, and if necessary, refer you to your doctor.

Bad breath in babies (3-12 months)

When bacteria build up in your babies’ mouth, the only sign may be their bad breath. Sinus infections, enlarged tonsils, bacteria on the tongue and acid reflux can also cause bad breath.

  • For most babies, teeth begin to appear at 6-10 months.
  • Rubbing babies’ gums or giving babies a cold object to suck might help with teething.
  • To prevent tooth decay, brush teeth twice a day, avoid sugary foods and drinks, and don’t put babies to bed with bottles.
  • Children should visit the dentist at around 12 months or when their first tooth appears.

If you’re concerned about your babies’ bad breath, you should consult your child’s doctor.

Bad breath in toddlers (1-3 years)

When bacteria build up in your toddler’s mouth, the only sign may be their bad breath. Sinus infections, enlarged tonsils, bacteria on the tongue and acid reflux can also cause bad breath.

  • For most children, all 20 baby teeth arrive by 3 years of age.
  • To prevent tooth decay, brush teeth twice a day, avoid sugary foods and drinks, and don’t put children to bed with bottles.
  • Use low-fluoride toothpaste from 18 months of age.
  • Children should see the dentist at around 12 months of age or when their first tooth appears.

If you’re concerned about your toddler’s bad breath, you should consult your child’s doctor.

https://www.colgate.com.au/oral-health/kids-oral-care/9-causes-of-bad-breath-in-children

Bad breath in kids

The most common cause of bad breath (halitosis) in young children is odorous bacteria within the mouth. Chronic reflux of stomach acids (gastroesophageal reflux disease, or GERD) foreign body, such as a piece of food or leftover food particles, lodged in a nostril can be also associated with bad breath.

Short term bad breath

Lung infection

When bad breath emanates from the lungs, sometimes the cause is a short-term infection. Some conditions like bronchitis, sinusitis and even pneumonia can cause foul breath.

https://www.colgate.com/en-in/oral-health/bad-breath/bad-breath-from-lungs--oral-hygiene-may-not-be-the-cause-#:~:text=When%20bad%20breath%20emanates%20from,pneumonia%20can%20cause%20foul%20breath.

Respiratory infection

Some issues unrelated to oral health can cause smelly breath. An upper respiratory infection like a cold or flu can cause bacteria to build up in the airway and respiratory system, which may cause nasty breath.

Or, the issue may be tonsillitis (infection of the tonsils) or tonsil stones. These can also lead to the buildup of bacteria and bad breath.

https://www.willowpediatricdentistry.com/post/explaining-the-5-most-common-causes-of-bad-breath-in-children

https://www.breathinstitute.co.uk/medical-library-bad-breath/causes-of-halitosis-bad-breath/respiratory-causes/

Sinus infection

The mucus in infected sinuses smells extremely unpleasant. Sinus infections cause bad breath as the infected, foul-smelling mucus drips from the sinuses down the back of the throat, where it meets tfhe air you exhale. This foul smelling odour transfers to your breath.

https://www.colgate.com.au/oral-health/bad-breath/sinus-infection-and-bad-breath#:~:text=The%20mucus%20in%20infected%20sinuses,odour%20transfers%20to%20your%20breath.

https://newsnetwork.mayoclinic.org/discussion/postnasal-drip-not-usually-related-to-bad-breath/

Bacterial infection

Sometimes, these bacteria start to break down proteins at a very high rate and odorous volatile sulphur compounds (VSC) are released from the back of the tongue and throat.

How do you know if you have bad breath?

To determine if you have bad breath, it is important to pay attention to the smell coming from your mouth and take note of any reactions from those around you.

Steps to determine if you have bad breath:

  • Ask your dentist if you have bad breath. A dentist can diagnose bad breath by examining your mouth and testing for bacteria that cause terrible breath.
  • Ask a trusted friend or family member: It can be embarrassing to ask someone how your breath smells, but it’s the best way to find out if you have an issue. Make sure it’s a person you trust, as they will be honest with you and help you identify any potential problems.
  • Check the back of your tongue: Your tongue can be an indicator for bad breath. If it’s coated in a white film, you could have bad breath.
  • Observe your saliva: Spit into a cup and wait about 10 minutes to see if any smell develops. If it smells, then you likely have bad breath.

If you haven't been to the dentist in a while, schedule an appointment as soon as possible.

Improving Hygiene Habits

Your fresh breath shopping list

  • Toothbrush (softest possible), we recommend electric by default, buy ones with a pressure light indicator, studies have shown you brush 25% better within the first 3 months of conversion. If you are good with your manual brushing stick with it. If you do buy a manual, get one with an included tongue scraper.
  • **Toothpaste **– Any toothpaste with fluoride (i.e. the cheapest Colgate)
    • Whitening toothpaste is just pure marketing – doesn’t work.
    • Any toothpaste with no fluoride is a scam. (Fluoride makes your teeth stronger against decay)
  • Dental floss (we recommend reach access flosser as it is the one that is the easiest to use compared to the traditional string types.
  • **Mouthwash, **use Colgate Peroxyl (contains 1.5% bleach – helps eliminate bad breath compared to other products which only COVERS it.
    It is important to use a mouthwash that is alcohol-free because alcohol can be too harsh for the delicate tissues in your mouth. Alcohol can dry out your mouth, which can lead to bad breath and an increased risk of tooth decay and gum disease. Alcohol-free mouthwashes are gentler on the teeth and gums while still providing protection against bacteria and harmful oral compounds. An alcohol-free mouthwash can provide fresher breath without leaving behind a burning sensation in your throat that is common with conventional alcoholic varieties. \

Brushing Regularly

Improving your oral hygiene routine can sometimes completely solve bad breath problems.

  • Ideally once in the morning and once before bed.
  • Brush after having breakfast (you don’t’ want to smell of your food before you go to work/school) and before going to bed.
  • If you are using electric toothbrush – light pressure enough to touch the teeth and cover all surfaces of your teeth.
  • You need to brush for a total of 2 minutes per session. Any less or more is not effective.
  • Dental appliances such as braces, retainers, and dentures should be cleaned regularly to remove bits of food particles and bacteria . \

Flossing Regularly

It is important to floss regularly in order to remove plaque and prevent the buildup of bacteria which can lead to gum disease, bad breath and other dental health issues.

  • The best time to floss is **before bed. **During the morning most people are in a rush to work/school
  • With reach access flosser, just do an up and down movement between teeth and that will get rid of bacteria and food debris.

Using Mouthwash

Use the mouthwash (peroxyl) as many times as you need.

  • Ideally twice day, after brushing.
  • Or before special events such as weddings, dates, or meeting your in-laws.
  • Follow the instructions on the mouthwash that you brought.

Only use the mouthwash (savacol) as directed by your dentist.

  • Usually, it is given to you to rinse for 1 minute before any surgery such as wisdom teeth removal to reduce the number of bacteria in your mouth
  • Post dental surgery (such as dental implants and wisdom teeth) to keep the area clean and reduce chances of infection.

Check our guide on the best mouthwash to buy.

Scraping the Tongue

Tongue scraping is an important part of fixing bad breath because it helps remove bacteria, dead cells, and bits of food stuck that can cause bad breath. This buildup can happen anywhere on the tongue but tends to accumulate near the back of the mouth where it's harder to reach with a toothbrush.

To brush your tongue, simply just scrape it as gently as possible with a soft bristled toothbrush (for electrics, turn them off!). Like how a cat licks.

Drinking Enough Water

Drinking enough water helps to keep your mouth moist, which in turn prevents bacteria from growing and causing bad breath. The saliva produced when you drink enough water also helps to wash away the food particles that can be left behind in your mouth, preventing them from fermenting and causing bad breath.

To keep your mouth moist, avoid tobacco and drink plenty of water — not coffee, soft drinks or alcohol, which can lead to a drier mouth, leading to an unpleasant mouth odor. Chew gum or suck on candy (preferably sugarless) to stimulate saliva. For chronic dry mouth, your dentist or physician may prescribe an artificial saliva preparation or an oral medication that stimulates the flow of saliva.

Avoid Sugary Foods

You should reduce sugar in your diet, which causes bacteria to accumulate and contributes to poor oral health.

Consuming healthy foods and drinks that are rich in calcium, phosphorus, and vitamins can promote good dental health. Additionally, crunchy fruits and vegetables can aid in removing food and plaque from the surfaces of teeth.

Avoid strong smelling foods

Avoiding foods with strong aromas can help to prevent bad breath.

You should also avoid eating too much protein which causes bacteria to accumulate and contributes to poor oral health.

Food and drink that's high in calcium, phosphorus and vitamins is good for your teeth. Crunchy fruits and vegetables can also assist in removing food and plaque from teeth surfaces.

Quitting Smoking

Smoking and using tobacco products are not only bad for your overall physical health, but can also lead to persistent bad breath. The chemicals in cigarettes and chewing tobacco irritate the gums, which can cause chronic inflammation and gum disease. The bacteria associated with gum disease can cause an unpleasant odor in the mouth. In addition, smoking itself can leave a layer of residue on teeth that further contributes to bad breath.

Alchohol and Caffeine

Drinking too much alcohol or caffeine can contribute to bad breath. This is because these drinks have a diuretic effect, meaning they increase urine production and reduce saliva production. Saliva is important for breaking down food particles in your mouth and washing away bad-smelling bacteria. When you don't produce enough saliva, the bacteria can multiply and cause bad breath.

To help reduce bad breath caused by drinking too much alcohol or caffeine, make sure to drink plenty of water throughout the day to stay hydrated and encourage saliva production.

Chewing Sugarless Gum or Mints

As well as temporarily freshening your breath, chewing gum can also promote saliva production if you have a dry mouth.

Make sure it's sugar free gum to avoid exposing your teeth to sugar that feeds bacteria in plaque.

https://www.mountlawleydental.com.au/blog/9-ways-to-beat-bad-breath

Other bad breath remedies. Do they work?

Recent scientific studies have shown that certain foods and drinks can help reduce bad breath.

Parsley

Parsley is a popular folk remedy for bad breath. The fresh scent and high chlorophyll content of it suggest that it may have a deodorizing effect. Studies (not done on human breath, however) have shown that parsley can potentially combat foul sulfur compounds.

Pineapple juice

Many people believe that pineapple juice is the quickest and most effective treatment for bad breath. Drink a glass of organic pineapple juice after every meal, or chew on a pineapple slice for one to two minutes.

It’s also important to remember to rinse your mouth of the sugars in fruit and fruit juice afterward.

There is limited scientific evidence to support this theory, but anecdotal reports suggest its effectiveness.

Water

Dry mouth often causes bad breath. Saliva plays a very important role in keeping your mouth clean. Without it, bacteria thrive.

Your mouth naturally dries out while you sleep, which is why breath is typically worse in the morning.

Prevent dry mouth by keeping your body hydrated. Drinking water, rather than caffeinated or sugary drinks, throughout the day can promote saliva production. Aim for at least eight glasses of water per day.

Yogurt

Yogurt contains healthy bacteria called lactobacillus. Healthy bacteria have the ability to combat harmful bacteria in different areas of your body, such as the gut.

Research shows that yogurt may also help reduce bad breath. A study revealed that after six weeks of consuming yogurt, 80 percent of participants experienced a decrease in bad breath. Probiotics in yogurt are effective in reducing the severity of bad breath.

To use yogurt to fight bad breath, eat at least one serving per day of plain, nonfat yogurt.

Milk

Milk is a well-known cure for bad breath. Research shows that drinking milk after eating garlic can significantly improve “garlicky” breath.

To use this method, drink a glass of low- or full-fat milk during or after a meal containing strong-smelling foods like garlic and onions.

Fennel or anise seeds

Since ancient times, fennel and anise seeds have been used to freshen breath. In certain regions of India, roasted fennel seeds are utilized as "mukhwas," or mouth fresheners, to purify breath after a meal. They taste sweet and contain aromatic essential oils that give the breath a fresh scent.

Fennel and anise seeds can be eaten plain, roasted, or coated with sugar.

Orange

Oranges not only make for a healthy dessert, but they also promote dental hygiene.

Many people have bad breath because they don’t produce enough saliva to wash away foul-smelling bacteria.

Research shows that vitamin C helps increase saliva production, which can help eliminate bad breathOranges are rich in this vitamin.

Zinc

Zinc salts, an ingredient in certain mouthwashes and chewing gum, can counteract bad breath. Zinc works to decrease the number of sulfurous compounds in your breath. Research has shown that regular rinsing with a solution containing zinc can be effective in reducing bad breath for at least 6 months.

Try a zinc chewing gum designed for people with dry mouth.

You can also find zinc dietary supplements at your local drug store or purchase them online here.

Green tea

Green tea is an effective home remedy for bad breath. Research shows that green tea has disinfectant and deodorizing properties that can temporarily freshen the breath. Mint has similar effects, so a cup of green mint tea may be an ideal breath freshener.

Brew two cups of tea before going to bed and refrigerate it overnight. Pour your cool tea into a water bottle and bring it to work. Slowly sip on it throughout the day. Purchase green mint tea here.

Apples

One study found that raw apples have a powerful effect against garlic breath. Certain natural compounds in apples neutralize the foul-smelling compounds in garlic. This is particularly useful for people whose garlic breath lingers, because it neutralizes the compounds in the bloodstream, rather than just deodorizing the mouth.

Homemade mouthwash with baking soda

Studies have shown that baking soda, also known as sodium bicarbonate, can effectively kill bacteria in the mouth. Research indicates that toothpastes containing high concentrations of baking soda effectively reduce bad breath.

To make a baking soda mouthwash, add 2 teaspoons of baking soda to 1 cup of warm water. Ensure to rinse your mouth with mouthwash for at least 30 seconds before spitting it out.

Homemade mouthwash with vinegar

Vinegar contains a natural acid called acetic acid. Bacteria tend to be inhibited in acidic environments, so using a vinegar mouthwash may help to reduce bacterial growth.

Add 2 tablespoons of white or apple cider vinegar to 1 cup of water. Gargle for at least 30 seconds before spitting it out.

https://www.healthline.com/health/home-remedies-for-bad-breath#see-a-doctor

https://www.croasdailedentalarts.com/blog/at-home-bad-breath-remedies/

What if you need some more help?

Your Dentist

See us every 6 months to help with gum and teeth cleaning to ensure that your breath is fresh! Let us know if you have any concerns about your dental health, and we'll develop a treatment plan suited to you.

Primary care provider

Don’t forget to look after yourself and do see your GP to check your stomach or GI issues if your bad breath continues.

If the source of your bad breath is unrelated to your dental health, the first thing to do will be to consult your general medical practitioner whom may need to look into your gastrointestinal, sinus and possibly your respiratory system.

Things not to do

Smoking tobacco

You have twice the risk for gum disease compared with a nonsmoker. The more cigarettes you smoke, the greater your risk for gum disease. The longer you smoke, the greater your risk for gum disease.

Don't put off oral healthcare

Don’t leave infections or issues to the last minute. Dentistry is easy and pain free if you have a preventive mindset. Please see us ASAP if you think you have an issue.

Don't forget to clean your teeth

Not clean your teeth. Dental decay occurs very fast, and you’d be surprised within a few weeks how things can go downhill.

Don't neglect your dentures

Treat your dentures like your car, need around a 6 month check up for it. Loose dentures give you painful ulcers, trap food which leads to more decay.

Don't rinse with water after cleaning your teeth

Toothpaste is designed to be consumed (they are all food safety grade certified in Australia, this applies to all adult and kids’ toothpaste). We want the sticky toothpaste to last between your teeth as long as possible (as least 30 minutes) for the fluoride integrate with your teeth.

Professional Treatments for Bad Breath

Dental Cleaning and Examinations

The dental hygienist uses a small mirror to check around your teeth and gums for any signs of gingivitis (inflamed gums) or other potential concerns.

For this procedure, our dentist or hygienist will use a scaler, which is a small metallic instrument that has a sharp, bladelike end. After we use the scaler to scrape off the tartar and plaque, we'll have you rinse with water, eliminating the debris particles that may have gotten dislodged.

https://www.healthline.com/health/dental-oral-health/what-happens-during-a-tooth-cleaning

Deep Cleaning, Such as Scaling and Root Planing

Our dentists will carry out a deep cleaning (also known as scaling and root planing) to thoroughly remove plaque and tartar residing around your teeth and under your gums.

  • Scaling removes tartar and bacteria from your tooth surfaces and below your gumline. It may be done using instruments, a laser or an ultrasonic device.
  • Root planing smooths the root surfaces. This helps prevent further buildup of tartar and bacteria. It also helps your gums attach to your teeth again.
  • Depending on your case, we may prescribe antibiotics as well. Topical or oral antibiotics can help control bacterial infection. Topical antibiotics can include antibiotic mouth rinses or putting gel containing an antibiotic into gum pockets. Sometimes oral antibiotics are needed to get of bacteria that cause infections.

Removing Plaque Buildup

With the small mirror to guide them, the dentist uses a scaler to get rid of plaque and tartar around your gum line, as well as in between your teeth. You’ll hear scraping, but this is normal. The more tartar there is in your mouth, the more time they’ll need to scrape a particular spot.

You can also ask your dentist if dental sealants are appropriate for you. Dental sealants may help to protect your teeth from cavities and decay.

https://coastaldentalcare.com.au/how-to-remove-dental-plaque/#:~:text=Your%20dentist%20or%20oral%20health,will%20remove%20any%20hardened%20tartar.

Treating Periodontal Disease

To avoid bad breath odour you may need to take extra steps to keep your gums healthy. There are several periodontal treatments available. The one that’s right for you depends on the severity of your condition and a number of other factors, including:

  • Your health.
  • Whether you smoke.
  • What treatments you’ve had in the past.

Dental cleaning and improved oral hygiene

People who have very early periodontal disease (gingivitis) may be able to reverse the condition with routine dental cleaning and improved oral hygiene. Because there’s no bone loss yet, this conservative approach gets rid of harmful oral bacteria before the disease has a chance to progress.

Proper oral hygiene includes brushing two to three times a day, flossing daily and visiting your dentist for regular exams and regular cleanings.

Scaling and root planing

Scaling and root planing is similar to routine dental cleaning. But it cleans deeper beneath your gums, removing plaque and bacteria where your toothbrush and floss can’t reach. Periodontists recommend this treatment for people with mild gum disease.

During this procedure, a dental hygienist cleans (scales) the plaque from your teeth and then smooths out (planes) your root surfaces to keep bacteria from reattaching. The procedure is usually done in at least two visits using local anesthesia.

Pocket reduction surgery

People with moderate to advanced gum disease may need pocket reduction surgery (also called osseous surgery). The goal is to remove plaque and tartar that are so deep under the gums that your hygienist can’t reach it. During this procedure, a periodontist makes an incision (cut) in your gums and creates a flap. This allows them to temporarily move your gums back from your teeth roots.

Next, they’ll clean the plaque, tartar and bacteria from your teeth roots and smooth out any rough areas. Once complete, they’ll reposition your gums and close the incision with stitches.

Oftentimes, periodontists combine pocket reduction surgery with other regenerative procedures, such as bone grafting, gum grafting or guided tissue regeneration.

LANAP (Laser-assisted new attachment procedure)

Some periodontists also offer pocket reduction with LANAP. This procedure treats periodontitis using a handheld laser. The laser targets diseased gum tissue while leaving healthy tissue intact.

LANAP is a less-invasive alternative to traditional pocket reduction surgery. But results are mixed.

Bone grafting

Your periodontist may use a dental bone graft to replace bone that you’ve lost to gum disease. Once they clean the infection out, they’ll place bone grafting material into the areas where the bone has eroded. This material acts as scaffolding or a space-holder, giving your body time to regenerate its own bone over time.

Gum grafting

If you’ve lost gum tissue to periodontal disease, your dentist may recommend gum graft surgery, also called tissue grafting. This procedure covers exposed teeth roots and adds thickness to your gum line.

During this procedure, a periodontist will add tissue to the areas of gum recession. This tissue may come from the roof of your mouth, or your provider may purchase it from a licensed bone and tissue bank.

Guided tissue regeneration (GTR)

Usually, periodontists use guided tissue regeneration in combination with a bone graft. GTR helps repair periodontal defects (areas of broken-down bone) and prevents soft tissue from growing into these areas.

During GTR, a periodontist places an artificial membrane between your gums and the newly placed bone grafting material. Soft tissue regenerates faster than bone, so the membrane keeps that space open so new bone can grow there instead of soft tissue.

Platelet-rich fibrin (PRF) and platelet-rich plasma (PRP)

Platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) contain growth factors that speed up healing and tissue regeneration. A periodontist can get PRF and PRP from a small sample of your blood. They’ll spin the sample in a centrifuge (a lab machine that spins rapidly, using centrifugal force) to separate plasma from your red blood cells. Then they’ll place the platelet-rich plasma or fibrin at the surgical site.

In addition to boosting healing, this type of therapy can also shorten recovery times and reduce post-surgical pain. And because it comes from your own blood, it’s completely safe.

https://my.clevelandclinic.org/health/diseases/21482-gum-periodontal-disease

References

  1. https://www.mayoclinic.org/diseases-conditions/bad-breath/symptoms-causes/syc-20350922
  2. https://www.healthline.com/health/dental-oral-health/what-happens-during-a-tooth-cleaning
  3. https://coastaldentalcare.com.au/how-to-remove-dental-plaque/#:~:text=Your%20dentist%20or%20oral%20health,will%20remove%20any%20hardened%20tartar.
  4. https://www.mountlawleydental.com.au/blog/9-ways-to-beat-bad-breath
  5. https://www.colgate.com.au/oral-health/kids-oral-care/9-causes-of-bad-breath-in-children
  6. https://dazzlingsmilesdental.com.au/why-does-gum-disease-cause-bad-breath/
  7. https://my.clevelandclinic.org/health/diseases/21482-gum-periodontal-disease