The Microbiome of the Mouth ?

 What is a microbiome?

A microbiome is a collection or community of microorganisms or microbes that affect the progression of health and disease. There are five identified microbiomes: gut, skin, vaginal, brain and oral. The oral microbiome is the collection of microbes, mostly bacteria, found within the mouth of humans and animals. 

What do microbes do in the mouth?

In the mouth, there are a variety of micro-environments which host different bacterial populations such as hard palate, the teeth, the area around tooth surfaces, the tongue and the areas above and below the gums. Each location has a unique composition of microbes. For example, some microbes are more suited to soft oral tissues, while others prefer harder tissues such as the enamel of teeth. Some live on dental plaque, which is a sticky residue on teeth, caused by the buildup of leftover food mixed with saliva. Some bacteria are harmful and some are beneficial. So far, more than 700 species of bacteria have been identified, making it the second most diverse biome of the body, second only to the gut.

How do cavities develop?

A cavity is a hole in a tooth that develops from tooth decay. 

Microbes thrive on sugary, starchy food and drinks which they convert to acids. It forms when acids in your mouth wear down the tooth enamel.

Cavities are preventable through proper oral hygiene which includes brushing, flossing, dental cleaning and a healthy diet.

Tooth cavities are also called dental caries.

Are all cavities the same?

Cavities can start on any tooth and are usually identified by where they occur. A smooth surface cavity is a slow-growing cavity where the enamel slowly dissolves. This often occurs in-between the teeth. Pit and fissures cavities form on the top part of a tooth’s chewing surface as well as the front side of the back teeth. Root decay more often happens to adults who have receding gums which exposes your roots to dental plaque and acid.

What are the 5 stages of tooth decay?

1. Demineralization: small, white, chalky spots may appear on the tooth.

2. Enamel decay: As decay progresses, the enamel breaks down and holes (cavities) may become noticeable as light brownish spots.

3. Dentin decay: Dentin is the softer layer just below the tooth enamel. Once plaque and bacteria reach the dentin, teeth become sensitive to hot, cold sweet or sour food and drinks and even cold air. Spots on the teeth become darker brown

4. Pulp damage: The innermost part of a tooth is the pulp, which contains nerves and blood vessels that transport nutrients to keep teeth alive. At this stage there is pain, redness and swelling in the gums around the tooth. Brown holes now may turn darker brown or black.

5. Abscessed tooth: A deep cavity can become infected forming a pocket of pus at the tip of the root and causing pain in your jaw or face. Usually facial swelling and swollen lymph nodes in the neck appear and the infection can spread to surrounding tissues and even other areas of the body.

How important is the oral microbiome?

Our first line of defense against invaders that can harm our bodies is the oral cavity, which is where it connects the alimentary canal, the immune system and the outside world. Oral bacteria that work in synergy are able to provide an important defence against invading bodies. An imbalance can create dysbiosis, an adverse effect that can contribute to diseases such as inflammatory bowel disease, Alzheimer’s, diabetes, pancreatic cancer and cirrhosis of the liver.

How does dysbiosis of the oral biome contribute to disease?

Dysbiosis of the oral microbiome significantly influences whole-body health. An imbalance will lead to inflammation, illness and disease. Events such as tooth decay, gingivitis, oral thrush occur in the mouth but can also have a major impact on gut and overall health. A major 2019 study in the Journal of Oral Microbiology discovered that bacterial populations from the mouth make their way to the gut microbiota and can alter immune responses and potentially lead to systemic diseases. This study names the P. gingivalis bacteria as one that is found in both a dysbiotic gut microbiome and oral cavities of those with chronic gum disease (periodontitis).

What is “leaky mouth”?

Dr. Cass Nelson-Dooley, MS, an ethnopharmacologist who has studied the oral microbiome extensively, jokingly called gingival epithelium permeability, “leaky mouth”, because she sees it as the oral equivalent of the “leaky gut”. She concluded that 45% of mouth bacteria make it to the rest of the body. 

Dr. Cass Nelson-Dooley's research 

How does oral infection cause major issues within the rest of the body?

Cass says that “Every time you swallow, you are seeding your gastrointestinal tract with bacteria, fungi, and viruses from your mouth—140 billion per day, to be exact.” 

The connection between chronic periodontitis and diabetes mellitus has been widely studied.

Bacteremia: bacteria can escape through the gum to the bloodstream leading to system-wide inflammation and infection of bacteria toxins that spread throughout the body. Two of the major oral bacterial groups that can impact overall health are Prevotella and Veillonella.

How are major body systems and functions impacted by the health of the oral microbiome?

1.Gastrointestinal Tract:

Inflammatory Bowel Disease (IBD) (includes diseases such as inflammatory bowel syndrome (IBS), 

Crohn’s disease and ulcerative colitis, all of which have chronic, persistent inflammation).  Since about 

2015, researchers have been noticing and studying connections between oral and dental symptoms such as dry mouth, mouth ulcers and inflammation of the lips and mouth. 

*Those with IBD have higher amounts of the following dominant pathogenic oral bacterial species: 

  Streptococcus, Prevotella, Neisseria, Haemophilus, Veillonella, and Gemella.

*Inflammatory responses in IBD are associated with dysbiosis of the oral microbiome.

*Some strains of Klebsiella bacteria in the mouth instigate the production 

of inflammatory TH1 cells  when they colonize within the gut. 

These antibiotic-resistant bacterial strains tend to colonize only in a gut that is already 

dysbiotic and can generate a severe gut inflammation.

Cirrhosis of the Liver

People who have cirrhosis (scarring) of the liver, have a specifically dysbiotic gut microbiome caused by bacterial species of which 54% originate in the mouth.

Gut-related Cancers

Advanced gum disease and tooth loss caused by oral pathogens, increase the risk of gastrointestinal, pancreatic and liver cancer. Oral bacteria  in the bloodstream or in the digestive system, cause systemic inflammation and could possibly activate carcinogens present in the mouth after smoking or drinking alcohol.

Helicobacter pylori (H. Pylori)

H. pylori is a very common bacteria in the mouth and can infect the stomach and cause peptic ulcers. Re-infection after antibiotic treatment is also common.

2.Immune System:

Although 70% of the immune system is located in your gut, immunity begins in the mouth. A large build-up of dental plaque (calculus) causes poorer immune responses to oral and systemic diseases. Disruptions to immunity not only affect the capacity to ward off colds or flu, but can also lead to heart disease and autoimmune conditions.

3.Cardiovascular Health:

Dysbiosis in the oral biome can lead to build up of plaque in arteries (atherosclerosis) and can limit oxygen throughout the body as well as nutrients in the bloodstream. There is a close correlation between periodontitis and cardiovascular disease.

4.Gut-Brain Axis:

Oral health may affect the risk for diseases of the brain and nervous system such as Alzheimer’s disease, anxiety and depression, because it influences the gut microbiome. A groundbreaking study released in early 2019 proposed a rare causative link (not just a correlation) between the P. gingivalis bacteria most responsible for gum disease and Alzheimer’s disease in the brain. There is also a direct correlation between poor dental health, tooth pain, bleeding gums, and anxiety/depression.

5.Endocrine System:

Risk of Diabetes increases dramatically after the development of periodontitis.

Adverse pregnancy problems/outcomes include preterm labor, preterm membrane rupture, preeclampsia, miscarriage, intrauterine growth retardation, low birth weight, stillbirth and neonatal sepsis. The oral bacteria, F. nucleatum, P. gingivalis and Bergeyella can be transferred by the mother from periodontal disease to placental and fetal tissues causing potential tissue damage and improper fetal development.

Obesity: In a 2009 study 98% of the obese women studied had high levels of the oral bacteria Selenomonas noxia in their saliva. They are unsure how this affects obesity and it warrants more study.  

Polycystic Ovarian Syndrome (PCOS) is linked to the quality of the gut biome; the pathogenic oral bacteria Prevotella is overabundant in the saliva of women with PCOS. 2016 study

6.Nitric Oxide Production:

Nitric Oxide is an important nutrient to the mouth and body which supports the body’s natural repair and maintenance. It is needed in all systems and can improve blood pressure, digestion, cancer risk, chronic inflammation, sleep, endurance and insulin resistance. When the oral microbiome contains a high number of nitrate-reducing bacteria, it decreases nitric oxide production which can lead to a cascade of problems.

What about the meridien system?

About 5000 years ago, the Chinese identified what we now know as the meridien system, a series of channels running throughout the body along which energy – or qi (chi) – flows.

Meridians pass through the body along 14 tangible channels carrying energy into and affecting every organ and every physiological system, including the immune, nervous, endocrine, circulatory, respiratory, digestive, skeletal (including teeth), muscular, and lymphatic systems.

Centuries later, a German dentist named Fritz Kramer thoroughly mapped out the specific energetic relationships between the teeth and organs – work that was essential to the development of biological dental medicine through the last half of the 20th century.

In a 2008 paper for Alternative Therapies, David Feinstein and Donna Eden cite some eye-opening work:

A study published in the Proceedings of the National Academy of Sciences in 1998 using functional magnetic resonance imaging (fMRI) demonstrated that stimulating an acupuncture point in the toe (each acupuncture point is believed to sit on the line of and regulate the energy in a particular meridian) activated the exact areas of the brain that would be predicted by acupuncture theory, despite no known anatomical pathways connecting the toe to that brain region. A special camera that registers biophotons in the spectral range of 200-800 nm shows that when stimulated, the meridians generate light along channels that are identical to the descriptions of meridians found in the texts of traditional Chinese medicine.

Not only are the oral bacteria affecting the whole body, but the energy flow or blockage is also influencing what happens throughout our body. 

How can we support the health of our oral microbiome?

1. Rethink What You Eat

Many foods help oral health by controlling the biofilm on your teeth and reducing plaque buildup. 

YES

• Eat mineral-rich foods like grass-fed dairy, high-quality seafood, and leafy greens.

• Get plenty of healthy fats, like grass-fed butter or ghee, fatty fish, nuts, healthy oils (coconut, avocado, and olive oils), and fatty cuts of grass-fed meats.

• Get as many non-starchy veggies in your diet as possible.

• Eat vitamin-K rich foods, like chicken liver, pastured eggs, and grass-fed butter.

• Drink a ton of filtered water to keep your mouth and body well-hydrated.

• Consider chewing sugar-free gum to help remineralize your teeth with xylitol.

NO

• Fill more than 15% of your plate with carbohydrates. The worst of these for your bacterial diversity include white bread, pasta, rice, crackers, and the like. 

• Eat sugary candy, cookies, or desserts every day. These can upset your biome in as little as 1 day.

• Drink soda, fruit juices, coffee, kombucha, or alcohol over long periods of time; sipping on these throughout the day contributes to demineralization. 

• Overeat wheat products, rice, and beans/legumes which are high in phytic acid, which can contribute to oral microbiome issues.

2. Brush and Floss Regularly

Brushing and flossing are key to biofilm and oral microbiome management; do it right after waking up, immediately before bed, and 30-45 minutes after a carbohydrate-rich meal.

4. Don’t Skip Your Cleanings

Profession teeth cleanings every 6 months are important to keeping your oral microbiome healthy. The plaque buildup your hygienist removes can otherwise contribute to the dysbiotic growth of pathogenic oral bacteria.

5. Scrape Your Tongue

The tongue is sometimes forgotten in the course of dental hygiene habits, tongue scraping. Scraping your tongue can remove the buildup of bacteria on the tongue and it can even make your food taste better.

6. Ditch the “Antiseptic” Mouthwash

Good bacterial diversity in the mouth is optimal so we don’t want to use mouthwash which kills “up to 99.9%” because it kills all the good bacteria as well as the harmful bacteria. Alcohol-based mouthwash dries out the mouth in addition to eliminating your mouth’s built-in immunities to oral disease. Instead, try a natural brand meant to support the microbiota of the mouth