What is biofilm?

Biofilm is a sticky substance that grows in moist environments like the human mouth, where it’s known as dental biofilm or plaque. It contains bacteria, viruses, and fungi. It forms quickly, contributes to bad breath, damages teeth by causing cavities, and harms gums and bone. Find out from a dental hygienist how to stop it.

We all encounter biofilm in daily life. If you have been wondering what biofilm is, or what dental plaque is made of, this article will provide clarification.

Biofilm contains bacteria and other microbes

Biofilm is a sticky substance that forms in moist environments, such as ponds, pet water bowls, and the human mouth. Dental biofilm, commonly known as plaque, adheres to the teeth and other oral tissues such as the tongue. Plaque is sticky and contains food particles. Dental biofilm also contains bacteria and other germs, such as viruses and fungi ^[2][4]. In fact, the COVID-19 virus is present in the biofilm of people with active, symptomatic cases of COVID ^[2]. Both good bacteria and bad bacteria comprise the oral environment. Bad bacteria in the oral microbiome are usually anaerobic (meaning they do not need air to survive) ^[1][5]. Good bacteria have a protective role in your oral health.

It forms quickly

Dental biofilm begins to form within minutes of brushing and flossing your teeth. Most people develop biofilm above the gumline at about the same rate ^[7]. However, people who have gum disease develop bad bacteria below the gum line at a faster rate than those with healthy gums ^[7].

It causes bad breath

Bacteria produce acid and other byproducts as it digests the foods and beverages you eat and drink. The bacteria and its waste products emit an unpleasant odor, which is a key factor in bad breath. Your oral pH can contribute to the formation of biofilm (bad bacteria love acidic environments), so your diet and other oral factors influencing pH may be making your bad breath worse ^[6].

It damages your teeth

Acid is a key factor in cavity formation, and the production of acid in the mouth is a vicious cycle. The more bad bacteria you have in your mouth, the more acidic your oral pH. The more acidic your oral pH, the more the bad bacteria grow and reproduce ^[6]. Teeth are made of minerals, and all this acid eats away at the calcium and phosphate in your enamel and tooth root surfaces ^[6]. With weakened tooth structure, cavities form.

It damages your gums and bone

The bad bacteria in your oral microbiome also damages your gums and the bone underneath. It hides underneath the gums in areas that your toothbrush may not be able to reach and actually makes its way through the gum tissue. The bacteria can even end up on the bone that surrounds the teeth. All of this bacterial invasion causes the immune system to respond, which ultimately causes permanent damage to the bone. The bone slowly begins to recede, leaving less and less supporting structure for the teeth ^[3].

It needs to be removed

As you now know, dental biofilm needs to be removed to prevent dental disease like cavities and gum disease. Twice daily removal of dental biofilm is recommended with brushing and flossing along with plaque disclosing tablets or other techniques your dental care professional recommends for you. Look for our other articles on how to protect your teeth and gums with effective oral home care!

Rachel Stroble

Rachel Stroble is a researcher, professor of dental hygiene at Rose State College in Oklahoma, and registered dental hygienist with 10 years of experience in dentistry. She supports education in the classroom with her own students, in the professional community through the development and presentation of continuing education courses, and you may have seen her articles in RDH Magazine, Today’s RDH, and the Oklahoma Dental Association Journal.

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References

1. AGGREGATIBACTER ACTINOMYCETEMCOMITANS – AAP Connect. (n.d.). Higher Logic, LLC. Retrieved September 17, 2022, from https://members.perio.org/libraries/glossary/entry?GlossaryKey=7601a9b2-e9ce-42dc-b36d-83059e33ac32&ssopc=1
2. Gomes, S. C., Fachin, S., Fonseca, J. G., Angst, P. D. M., Lamers, M. L., Silva, I. S. B., & Nunes, L. N. (2021). Dental biofilm of symptomatic COVID‐19 patients harbours SARS‐CoV‐2. Journal of Clinical Periodontology, 48(7), https://doi.org/10.1111/jcpe.13471
3. Lasserre, J. F., Brecx, M. C., & Toma, S. (2018). Oral Microbes, Biofilms and Their Role in Periodontal and Peri-Implant Diseases. Materials, 11(10), https://doi.org/10.3390/ma11101802
4. Matsumoto-Nakano, M., (2018). Role of Streptococcus mutans surface proteins for biofilm formation. Japanese Dental Science Review 54(1), http://dx.doi.org/10.1016/j.jdsr.2017.08.002
5. PORPHYROMONAS GINGIVALIS – AAP Connect. (n.d.). Higher Logic, LLC. Retrieved September 17, 2022, from https://members.perio.org/libraries/glossary/entry?GlossaryKey=965ec455-2938-4d54-9947-196ea454164b&tab=groupdetails&ssopc=1
6. Tarcísio Jorge Leitão, Jaime, A. C., & Livia Maria Andaló Tenuta. (2018). Kinetics of calcium binding to dental biofilm bacteria. PLoS One, 13(1) https://doi-org.argo.library.okstate.edu/10.1371/journal.pone.0191284
7. Uzel, N. G., Teles, F. R., Teles, R. P., Song, X. Q., Torresyap, G., Socransky, S. S., & Haffajee, A. D. (2011). Microbial shifts during dental biofilm re-development in the absence of oral hygiene in periodontal health and disease. Journal of Clinical Periodontology, 38(7), https://doi.org/10.1111/j.1600-051X.2011.01730.x