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Dental plaque identification at home

Plaque is a soft and sticky substance that collects around and between teeth. The home dental plaque identification test shows where plaque builds up. This helps you know how well you are brushing and flossing your teeth.

Plaque is the major cause of tooth decay and gum disease (gingivitis). It is hard to see with the naked eye because it is whitish colored, like teeth.

How the Test is Performed

There are two ways to perform this test.

  • One method uses special tablets that contain a red dye that stains the plaque. You chew 1 tablet thoroughly, moving the mixture of saliva and dye over your teeth and gums for about 30 seconds. Then rinse your mouth with water and examine your teeth. Any red-stained areas are plaque. A small dental mirror may help you check all areas.
  • The second method uses a plaque light. You swirl a special fluorescent solution around your mouth. Then rinse your mouth gently with water. Examine your teeth and gums while shining an ultraviolet plaque light into your mouth. The light will make any plaque look bright yellow-orange. The advantage of this method is that it leaves no red stains in your mouth.

In the office, dentists and dental hygienists are often able to detect plaque by doing a thorough exam with dental tools.

How to Prepare for the Test

Brush and floss your teeth thoroughly.

How the Test will Feel

Your mouth may feel slightly dried out after using the dye.

Why the Test is Performed

The test helps identify missed plaque. It can encourage you to improve your brushing and flossing so that you remove more plaque from your teeth. Plaque that remains on your teeth can cause tooth decay or make your gums bleed easily and become red or swollen.

Normal Results

No plaque or food debris will be seen on your teeth.

What Abnormal Results Mean

The tablets will stain areas of plaque dark red.

The plaque light solution will color the plaque a bright orange-yellow.

The colored areas show where brushing and flossing was not sufficient. These areas need to be brushed again to get rid of the stained plaque.

Risks

There are no risks.

Considerations

The tablets may cause a temporary pink coloring of your lips and cheeks. They may color your mouth and tongue red. Dentists suggest using them at night so that the color will be gone by morning.

References

Hughes CV, Dean JA. Mechanical and chemotherapeutic home oral hygiene. In: Dean JA, ed. McDonald and Avery's Dentistry of the Child and Adolescent. 11th ed. St Louis, MO: Elsevier; 2022:chap 8.

Jahn CA, Mancinelli-Lyle D. Plaque biofilm control for the periodontal patient. In: Newman MG, Klokkevold PR, Elangovan S, Hernandez-Kapila YL, eds. Newman and Carranza's Clinical Periodontology and Implantology. 14th ed. St. Louis MO: Elsevier; 2023:chap 50.

National Institute of Dental and Craniofacial Research website. Periodontal (gum) disease. www.nidcr.nih.gov/health-info/gum-disease. Updated August 2024. Accessed August 7, 2024.

Review Date 3/31/2024

Updated by: Michael Kapner, DDS, General Dentistry, Norwalk Medical Center, Norwalk CT. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. Editorial update 08/07/2024.

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