Halitosis

Halitosis (also known as bad breath or fetor oris breath) affects an estimated 25 percent of people. Halitosis can be embarrassing and, in some cases, may even cause anxiety.

Halitosis is the general term used to describe any disagreeable odor in exhaled air, regardless of whether the odorous substances originate from oral or non-oral sources. There are a number of possible causes of halitosis, but the vast majority come down to oral hygiene. Ninety percent of causes of halitosis are associated with oral components. Approximately 5%–9% of halitosis originates from non-oral structures such as the respiratory and gastrointestinal tract, and only 1% of bad breath is caused by medicine.

About 25% of individuals with halitosis experience such a severe problem that it affects their social functioning. This can cause a loss of confidence and self-esteem.

Risk Factors

Your risk of bad breath is higher if you eat foods known to cause bad breath, such as garlic, onions, and spices. The factors that increase the likelihood of halitosis include periodontal diseases, dry mouth, smoking, alcohol consumption, dietary habits, diabetes, and obesity.

Halitosis can also be affected by the general hygiene of the body (i.e., dehydration, starvation, and high physical exertion), advanced age, bleeding gums, decreased brushing frequency, but also by stress. Produced during stress, catecholamines and cortisol increased hydrogen sulfide production by sub-gingival anaerobic bacteria.

Drugs

The medications which can cause extra-oral halitosis were categorized into 10 groups: acid reducers, aminothiols, anticholinergics, antidepressants, antifungals, antihistamines and steroids, antispasmodics, chemotherapeutic agents, dietary supplements, and organosulfur substances. 

Candida

Candida albicans is a naturally occurring fungus that lives on your body. Candida may be involved in halitosis. Candida species cause oral candidiasis, most commonly Candida albicans.

Candida is part of the normal oral microflora of immunocompetent individuals. Around 30 to 60% of adults and 45 to 65% of infants carry candida species in their oral cavities. Most of these species live in the oral cavity as a commensal population rather than a pathological one.

A coated (furred) tongue has recently been considered as a cause of halitosis. Various microorganisms exist on a coated tongue. Of these, Candida is the most frequently detected, reflecting the oral environment.

A tongue coating is formed with food and bacteria, facilitating the growth of Candida. The overgrowth of Candida in the oral cavity is caused by oral environmental deterioration (e.g., immune compromise, aging, decreased salivation, periodontal diseases, steroid use, and antibiotic use). A disturbance in the balance between commensal microbiota and the host immune system results in a switch from a healthy state to a diseased state even in the limited oral niche. 

When Candida yeast changes to its virulent fungal form, it grows long branches (hyphae) that can extend into your soft tissue. These can release waste products. The toxic byproducts that are released include acetaldehyde, ammonia, and uric acid. 

Sulfur-producing Bacteria

Halitosis is mostly caused by sulfur-producing bacteria that normally live on the surface of the tongue and in the throat. Sometimes, these bacteria start to break down proteins at a very high rate and odorous volatile sulfur compounds are released from the back of the tongue and throat. 

Halitosis is mainly formed by volatile organic compounds caused by pathological or non-pathological causes. These volatile organic compounds are sulfur compounds, aromatic compounds, nitrogen-containing compounds, amines, short-chain fatty acids, alcohols or phenyl compounds, aliphatic compounds, and ketones. 

In the oral cavity, nearly 700 different compounds have been detected. Hydrogen sulfide, methyl mercaptan, and dimethyl sulfide are the main volatile compounds in intra-oral halitosis. The 30 most abundant volatile compounds in the oral cavity belong to alkanes or alkane derivatives, therein methyl benzene, tetramethyl butane, and ethanol. 

Volatile sulfur compounds can be toxic for human cells even at low concentrations. Methanethiol also known as methyl mercaptan is an organosulfur compound. It is a colorless gas with a distinctive putrid smell. It is one of the chemical compounds responsible for bad breath and the smell of flatus. 

Oral bacteria break down organic substrates (such as glucose, proteins present in saliva, oral soft tissue, and residual debris) and produce odorous compounds. Gram-negative bacteria, mostly Enterobacteriaceae, which can colonize the oral cavity and dentures, produce urease that hydrolyzes urea into carbon dioxide and ammonia.

Smoking

Tobacco smoking is the second greatest offender in the development of halitosis, behind periodontal disease and the associated food stagnation. Smoking causes a decrease in the commensal population of normal flora in the oral cavity, leading to an increase in pathogenic microbes as well as enhancement of microbial colonization by biofilm formation on oral epithelial cells.

More importantly, smoking increases the probability of extensive disease development, and contributes to halitosis by causing hyposalivation.

Tobacco products cause their own types of mouth odor. Additionally, they increase the chances of gum disease which can also cause bad breath.

Dry Mouth

Saliva naturally cleans the mouth. If the mouth is naturally dry or dry due to a specific disease, such as xerostomia, odors can build up.

Other Causes

Sometimes, small, bacteria-covered stones can form on the tonsils at the back of the throat and produce odor. Also, infections or inflammation in the nose, throat, or sinuses and a foreign body lodged in the nasal cavity can cause halitosis.

Some cancers, liver failure, and other metabolic diseases can cause halitosis, due to the specific mixes of chemicals that they produce. Gastroesophageal reflux disease can cause bad breath due to the regular reflux of stomach acids.

Symptoms of Halitosis

Halitosis has many causes, and so the symptoms are going to vary depending on the person. Some cases are temporary and will disappear after some time.

Symptoms may include dry mouth, change in taste, a white coating on the tongue especially at the back of the tongue, build up around teeth, post-nasal drip, or mucous, morning bad breath, a burning tongue, thick saliva, a constant need to clear the throat, constant sour, and bitter metallic taste.

Prevention Tips

Proper oral hygiene is the best way to keep your breath smelling clean and fresh. 

Brush twice a day, for at least two minutes each time, and floss once a day. Remember to clean your tongue with your brush or a tongue scraper. Use an alcohol-free antibacterial mouthwash. See your dentist regularly for checkups and cleanings. 

Drink a lot of water to help prevent dry mouth. Boost the production of saliva by using sugar-free chewing gum, or eating healthy foods that require a lot of chewing. Avoid alcohol, caffeine, and tobacco products because they can dry out your mouth. Avoid onions, garlic, and spicy food. Sugary foods are also linked to bad breath. Eating a breakfast that includes rough foods can help clean the back of the tongue.

Anything that goes into your mouth, including dentures, a bridge, or a mouth guard, should be cleaned as recommended on a daily basis. Cleaning prevents the bacteria from building up and being transferred back into the mouth.