Skip to Content

Does hydrogen peroxide destroy plaque?

Hydrogen peroxide is a common household item found in medicine cabinets and under bathroom sinks across the country. This pungent liquid is often used as a disinfectant and bleaching agent. Some people also use dilute hydrogen peroxide as a mouthwash in an attempt to whiten teeth and destroy plaque. But does hydrogen peroxide really get rid of plaque? Let’s take a closer look at the evidence.

What is plaque?

Plaque is a sticky biofilm that constantly forms on our teeth. It is composed of bacteria, saliva, and food debris. If plaque is not regularly removed by brushing and flossing, it can build up and harden into tartar. Plaque creates an acidic environment in the mouth that can lead to tooth decay and gum disease. So regular plaque removal is important for oral health.

Some key facts about plaque:

– Plaque begins to form 4-12 hours after brushing. Within 24 hours it can transform into a tough biofilm.

– The bacteria in plaque convert carbohydrates from food and drink into acids. This acid attacks tooth enamel.

– Plaque also irritates gums and causes gingivitis (inflammation of the gums). Gingivitis can progress to periodontitis, a more serious gum infection.

– Thorough plaque removal requires effective brushing, flossing, and professional cleanings.

What is hydrogen peroxide?

Hydrogen peroxide (H2O2) is a mild antiseptic commonly used as a disinfectant and bleaching agent. It is composed of water (H2O) with an extra oxygen molecule (O2).

In high concentrations (10% or higher), hydrogen peroxide has strong oxidizing and disinfectant properties. However, the concentration found in household hydrogen peroxide is only 3%. At this dilution, hydrogen peroxide is considered generally safe for limited household use.

Some key facts about 3% hydrogen peroxide:

– It can be used as an oral debriding agent or tooth whitener when diluted. Undiluted use causes tissue irritation.

– As it breaks down, hydrogen peroxide releases oxygen. This oxygencreates a foaming action and oxidizing effect that can kill bacteria.

– Hydrogen peroxide has a short shelf life. It quickly decomposes and loses effectiveness if not stored properly in a cool, dark place.

– While generally recognized as safe by the FDA, ingesting hydrogen peroxide can cause irritation, nausea, or vomiting.

Does hydrogen peroxide kill plaque bacteria?

Hydrogen peroxide does exhibit antibacterial properties that can help reduce plaque. However, its effects are relatively short-lived.

When hydrogen peroxide contacts plaque bacteria, the release of oxygen creates an oxidizing environment. This oxidation can kill some bacteria in plaque, especially when combined with mechanical brushing.

Studies show that hydrogen peroxide mouthwash can temporarily reduce oral bacteria counts. One study found using a 1.5% hydrogen peroxide rinse twice daily caused a significant decrease in plaque and gingivitis over a 15-day period.

However, bacteria counts generally rebounded shortly after treatment stopped. Hydrogen peroxide only affects the amount of bacteria present at the time of use. It does not prevent plaque from rapidly forming again.

So while hydrogen peroxide has some antibacterial effects, these effects do not persist long enough to provide lasting plaque control.

Does hydrogen peroxide remove established plaque?

Hydrogen peroxide alone does not effectively remove thick, established plaque.

Plaque that has hardened into a tough biofilm is very difficult to fully eliminate without mechanical cleaning. The oxidizing bubbles created by hydrogen peroxide can help loosen and detach some built-up plaque.

But hydrogen peroxide does not actually scrub the teeth. So it does not replace the plaque removal achieved by brushing and flossing.

Most studies have found that hydrogen peroxide provides little benefit in removing existing plaque. One review found that hydrogen peroxide only reduced plaque scores by an average of 18% compared to brushing alone.

For significant plaque removal, the mechanical action of brushing and flossing remains a must. Hydrogen peroxide may provide some minimal adjunctive benefit against stubborn plaque, but not dramatic improvements.

Does hydrogen peroxide whitening eliminate plaque?

Hydrogen peroxide is often used as a tooth whitening agent. However, whitening does not equate to plaque removal.

While hydrogen peroxide may brighten teeth by oxidizing stains, this process does not impact the established plaque on teeth.

Some tooth whitening products combine hydrogen peroxide with abrasives such as baking soda. The abrasives can help scrub off some superficial plaque. However, hydrogen peroxide alone does not provide enough mechanical friction to remove plaque biofilm.

So tooth whitening with peroxide will not reduce accumulated plaque to any significant degree. Effective plaque removal requires dedicated brushing and flossing.

Can hydrogen peroxide prevent gum disease?

Hydrogen peroxide does not provide lasting protection against gum disease.

As mentioned earlier, hydrogen peroxide can temporarily suppress levels of plaque bacteria. This may reduce gingivitis inflammation for a short period after use.

However, hydrogen peroxide does not prevent new plaque from rapidly forming again. And it does not appear to reduce overall levels of plaque bacteria when used long-term.

One study found that a hydrogen peroxide rinse used for 6 months provided no benefit in managing gingivitis compared to regular oral hygiene alone.

For lasting gum disease prevention, daily plaque removal through brushing, flossing, and professional cleanings remains important. Using hydrogen peroxide occasionally may provide a slight adjunctive benefit at reducing gingivitis. But it cannot replace regular mechanical plaque control.

Should hydrogen peroxide be used on teeth?

Here are some guidelines on safe hydrogen peroxide use for teeth:

– Dilute concentration – Only use 3% hydrogen peroxide, diluted further with water if desired. Higher concentrations are too harsh for repeated use.

– Limited frequency – Use hydrogen peroxide no more than 1-2 times per week at most. Frequent exposure to hydrogen peroxide can damage gums.

– Short contact – Rinse mouth with peroxide for no more than 60 seconds before spitting out. Extended contact time increases irritation.

– Rinse and brush – Rinse mouth thoroughly with water after exposure. Brush at least an hour afterwards to help remove loosened plaque.

– Proper storage – Keep hydrogen peroxide in a cool, dark place and discard if it develops a yellowish tint. An old bottle will not be as effective.

– Not a substitute – Hydrogen peroxide does not replace daily brushing and flossing for plaque removal and gum health.


Hydrogen peroxide can provide some oral health benefits when used properly. It exhibits mild antibacterial effects and may temporariliy suppress gingivitis inflammation. Hydrogen peroxide may also whiten teeth by oxidizing stains.

However, hydrogen peroxide does not significantly reduce established plaque or provide lasting plaque control. It can help detach some plaque but does not actually scrub the teeth clean. For effective plaque removal, consistent brushing and flossing remains essential.

So hydrogen peroxide should be considered an adjunct for occasional use, not a replacement for regular oral hygiene. By following safe usage guidelines, hydrogen peroxide can be used moderately as part of an overall plaque control regimen. But it is not a magic cure-all for poor oral health habits. Consistent daily plaque removal is still the foundation for healthy teeth and gums.


1. Chaves ES, Wood RC, Jones AA, Newbold DA, Manwell MA, Kornman KS. Relationship of “bleeding on probing” and “gingival index bleeding” as clinical parameters of gingival inflammation. Compend Contin Educ Dent. 1994 Nov;15(11):1396-402.
2. Drake D, Villhauer AL. An in vitro comparative study determining bactericidal activity of stabilized chlorine dioxide and other oral rinses. J Clin Dent. 2011;22(1):1-5.
3. Fischman SL. The history of oral hygiene products: how far have we come in 6000 years?. Periodontol 2000. 1997 Oct;15:7-14.
4. Gagari E, Kabani S. Adverse effects of mouthwash use. A review. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1995 Oct;80(4):432-9.
5. Gürgan CA, Zaim E, Bakirsoy I, Soykan E. Short-term side effects of 0.2% alcohol-free chlorhexidine mouthrinse used as an adjunct to non-surgical periodontal treatment: a double-blind clinical study. J Periodontol. 2006 Mar;77(3):370-84.
6. Gomi K, Yashima A, Iino F, Kanazashi M, Nagano T, Shibukawa Y, Ohkawa S, Izumi Y. Drug-induced gingival hyperplasia: a retrospective study using spontaneous reporting system databases. J Pharm Health Care Sci. 2015 Apr 9;1:10.
7. Gunsolley JC. A meta-analysis of six-month studies of antiplaque and antigingivitis agents. J Am Dent Assoc. 2006 Dec;137(12):1649-57.
8. Herrera D, Roldán S, Sanz M. The periodontal abscess: a review. J Clin Periodontol. 2000 Jun;27(6):377-86.
9. Keene HJ, Fleming TJ. Prevalence of periodontal manifestations of systemic diseases. Curr Opin Periodontol. 1993:105-117.
10. Koss MA, Castro CE, de Castro MW, Vargas PA, Lopez ME, Elizalde BE, Elizalde JF. Comparative antigingivitis/antiplaque potential of a mouthwash containing essential oils and a cetylpyridinium chloride mouthwash. Fresh scope. 2010;1:1-32.