What is the Relationship Between Oral Diseases and the Oral Microbiome?

older man smiling oral health

Oral health is a complex state that requires cooperation from natural biological processes and the microbes that live inside the oral cavity. To best support oral health, it is important to take into consideration these dynamic influences and how they relate to the teeth, gums, tongue, and other oral tissues.

What is the Oral Microbiome?

The oral microbiome consists of over 700 different kinds of microorganisms that live within the mouth1. Through the Human Microbiome Project, scientists have mapped out the diverse range of bacteria and other microorganisms that thrive within the human body. Using this information, scientists are now studying their impact on human health. 

Significant evidence has linked bacteria to many human disease states, including cancers of the mouth and a variety of periodontal diseases2. 

However, there is also evidence that many bacteria within the oral cavity also support and promote positive activities on health such as:

  • Digestion 

  • Blood pressure

  • Teeth remineralization

  • Waste removal

  • Increasing access of oxygen to cells in the mouth

  • Preventing inflammation3

These depend on how healthy an individual’s oral microbiome is and the types compounds these bacteria may create within the mouth. 

What Impacts the Oral Microbiome?

A number of factors can influence the microbiota inside the mouth. This includes diet, dental hygiene, age, health status, medication, tobacco use, and more4. Together, these factors can impact issues like biofilm formation or how acidic the oral environment may be. 

Biofilm Formation

The bacteria in the oral microbiome generate structures called biofilm that attach to the surface of the teeth, gums, and other tissues within the mouth5. Also known as dental plaque, these structures help bacteria establish a community and support their growth and proliferation inside the mouth.

The production and formation of biofilm has been closely related to many oral diseases such as dental caries (cavities) and periodontitis5. These diseases can impact oral health and increase the likelihood of health issues spreading to other areas of the body. 

Maintaining a healthy dental routine by brushing and flossing regularly can help break apart plaque deposits from biofilm within the mouth.

Oral pH

The level of acidity within the oral cavity has been directly associated with a number of dental conditions. Having a low pH - or a highly acidic environment - within the mouth can support the growth of harmful and pathogenic microorganisms6. Certain lifestyle habits can make the level of acidity within the mouth worse. 

To help make the oral cavity and saliva levels more neutral, avoid sugar, drinking alcohol, using drugs, and smoking. 

Signs of an Unhealthy Oral Microbiome

Many pathogenic and harmful microbes can contribute to swaying the balance within the oral microbiome. As this ecosystem shifts, a number of signs can appear suggesting that your oral microbiome may be imbalanced. These might include:

  • Bad breath

  • Plaque buildup on the teeth

  • Tooth decay

  • Receding gums

  • Endodontic infections

  • Frequent respiratory infections7

Over time, an unhealthy oral microbiome can contribute to a number of diseases that take advantage of an oral environment that is out of balance. 

Tips for Oral Microbiome Health

Though there is no one single way to improve overall oral health, maintaining a balanced oral microbiome may help reduce the risk of oral diseases and should be included in any oral health strategy.

Dental Hygiene Habits

As previously described, regular brushing and flossing can help break apart plaque that contributes to the growth of bacteria inside the mouth8. It is important to note that using too harsh of a bristle or applying too much pressure to the teeth and gums during brushing can do more harm than good. Additionally, common mouthwashes containing alcohol or other detergents can help rid the mouth of bad bacteria, but can also harm the levels of beneficial bacteria. 

Saliva Production

Used to carry digestive enzymes, hydrate the oral cavity, fight harmful bacteria, and bring nutrients, minerals, and proteins to the mouth, saliva is one of the most powerful natural mechanisms for oral health9. You can promote saliva production by staying hydrated. Other natural ways to increase saliva production include chewing sugar-free gum to help stimulate the mouth to produce more saliva.

Fibrous Foods

Fiber is known as a common prebiotic which can help feed beneficial microorganisms within the mouth. Chewing fiber-rich foods also can help naturally clean the teeth and act as nature’s toothbrushes10. Many fiber-rich foods include cruciferous vegetables - like broccoli and kale - or celery. 

Alkaline-rich Foods

An acidic environment within the mouth can greatly contribute to an imbalance within the oral microbiome. Taking in nutrient-dense and alkaline-rich foods can help reduce the level of acid found within the mouth and the saliva. These foods include fresh vegetables, avocado, apricots, coconut, beans, lentils, alkaline water, and green tea11.

Keeping these tips in mind can help support your oral microbiome and improve oral health. It is also important to schedule regular checkups with a licensed professional for routine cleanings. Your dental health professional can help identify problems in your oral health early on so you can receive the proper support and recommendations you need for improved oral health.

  1. Xian, P. et al. The oral microbiome bank of China. Int J. Oral. Sci.10, 16 (2018).

  2. Nejman, D. et al. The human tumor microbiome is composed of tumor type-specific intracellular bacteria. Science368, 973–980 (2020).

  3. Deo, P. N., & Deshmukh, R. (2019). Oral microbiome: Unveiling the fundamentals. Journal of oral and maxillofacial pathology : JOMFP, 23(1), 122–128.

  4. Sharma, N., Bhatia, S., Sodhi, A. S., & Batra, N. (2018). Oral microbiome and health. AIMS microbiology, 4(1), 42–66.

  5. Berger, D., Rakhamimova, A., Pollack, A., & Loewy, Z. (2018). Oral Biofilms: Development, Control, and Analysis. High-throughput, 7(3), 24.

  6. Baliga, S., Muglikar, S., & Kale, R. (2013). Salivary pH: A diagnostic biomarker. Journal of Indian Society of Periodontology, 17(4), 461–465.

  7. Krishnan, K., Chen, T., & Paster, B. J. (2017). A practical guide to the oral microbiome and its relation to health and disease. Oral diseases, 23(3), 276–286.

  8. Deo, P. N., & Deshmukh, R. (2019). Oral microbiome: Unveiling the fundamentals. Journal of oral and maxillofacial pathology : JOMFP, 23(1), 122–128.

  9. Kilian, M., Chapple, I. L., Hannig, M., Marsh, P. D., Meuric, V., Pedersen, A. M., Tonetti, M. S., Wade, W. G., & Zaura, E. (2016). The oral microbiome - an update for oral healthcare professionals. British dental journal, 221(10), 657–666.

  10. Sedghi, L., Byron, C., Jennings, R., Chlipala, G. E., Green, S. J., & Silo-Suh, L. (2019). Effect of Dietary Fiber on the Composition of the Murine Dental Microbiome. Dentistry journal, 7(2), 58.

  11. Gordan, V. V., McEdward, D. L., Ottenga, M. E., Garvan, C. W., & Harris, P. A. (2014). Alkali production in the mouth and its relationship with certain patient's characteristics. Journal of applied oral science : revista FOB, 22(6), 560–568.