What Is Plaque?

A couple stands in a bathroom brushing their teeth
A key to a successful marriage may be not to move in or marry before age 23, new research suggests.
Credit: Toothbrushing photo via Shutterstock

Dental plaque is a sticky, clear film of bacteria that forms on teeth. It collects on teeth and between teeth, and forms both above and below the gum line. It collects all over the mouth but it tends to especially accumulate in and around the molars’ deep crevices.

Though it is mostly colorless, dental plaque can cause teeth to feel fuzzy or rough if it accumulates. The presence of dental plaque causes dental problems, so plaque should be removed regularly.

Dental plaque definition

Dental plaque is a microbial biofilm, a highly diverse microbial community. The microbes exist with other organic and inorganic materials and are involved in various physical, metabolic and molecular interactions. The interactive and cooperative nature of these microbes makes plaque especially resistant to antimicrobial agents.

Dental plaque is so named because, if greatly accumulated, it can take on a yellowish color. This is reminiscent ofmucosal plaques caused by syphilis. If you want to see your dental plaque, there are dyes available that make it visible on teeth.

How does plaque form?

Plaque is forming at all times, even when you are not eating. Dental plaque is the result of chemical reactions that take place naturally in the mouth. To exist, plaque needs bacteria, carbohydrates, food particles and saliva. After you eat food with carbohydrates, the carbohydrates combine with the mouth’s natural bacteria to create an acid. The acid then combines with old food particles and saliva in another chemical reaction that causes the microbial substance to become sticky and harder. This substance is dental plaque.

Problems and risks

The microbes in dental plaque feed on the foods we eat when remnants of them are left on our teeth, which happens frequently (we can’t usually see these deposits). Dental plaque microbes especially like foods that contain carbohydrates, including all starchy and sugary foods like candy, fruit, soft drinks and other sweets.

When food deposits are present, the microbes grow in number, congregating in clumps to eat. As they eat, they produce acids. Overtime, these acids begin to eat their way through tooth enamel, destroying it and causing tooth decay (cavities), which can lead to tooth abscesses. Dental plaque can also develop on the tooth roots under the gum line. In this case, the acids break down the bone supporting the tooth.

Dental plaque near the gum line can also lead to gingivitis, a mild form of gum disease that can eventually cause more serious periodontitis. In this case, the plaque produces toxins that irritate the gums, causing them to swell, bleed, and become infected.

Dental plaque that remains on the teeth for several days hardens and becomes a hard, dense substance called tartar. Tartar is difficult to remove and must be actively scraped off teeth by a dentist or dental hygienist. It can give teeth a yellowish appearance and bad smell, as well as contribute to gum disease.

How to get rid of plaque

Plaque is dangerous but there is no way to stop its growth completely. Therefore, it is important to remove it regularly before the acid begins to cause tooth decay, the toxins begin to cause gum disease, and before it turns into tartar.  

To remove dental plaque, brush your teeth at least twice a day. If you are concerned about plaque buildup, consider brushing after every meal or snack as well as before bedtime. Floss at least once a day. You should also get a professional dental cleaning every six months and a dental exam and X-rays once a year. During the cleaning, the dentist or dental hygienist will remove all traces of plaque and tartar from the mouth in a process known as “scaling.”

To prevent dental plaque from building up, eat a balanced diet with limited sugar and carbohydrates for the microbes to eat. Limiting between-meal snacks can help because the acid production escalates every time food is eaten. You can also ask your dentist about sealants, which are thin, protective plastic-like coatings that are applied to the chewing surfaces of back molars, where plaque tends to be especially prevalent. Sealants are often applied to young children’s teeth, but adults can benefit from them as well.

Editor's Recommendations

More from LiveScience