Brushing and flossing are the cornerstones of oral health, but mouthwash can be a valuable addition to your routine. However, with countless options boasting various benefits – from fighting plaque and freshening breath to strengthening teeth – confusion often swirls around its effectiveness. It is crucial to harness the power of mouthwashes and maximize their impact for a healthy and happy mouth.
Mouthwashes (mouth rinses or oral washes or oral rinses) are liquid, aqueous compositions mainly intended to prevent, relieve, and cure oral conditions:
Gingivitis
Mucositis (inflammatory and/or ulcerative lesions of the oral mucosa)
Mouthwashes aid in reducing the oral microbiota and maintaining oral health. Mouthwash is held in the mouth passively or swirled around the mouth by contraction of the perioral muscles and/or movement of the head, or maybe gargled and finally spit out.
Mouthwashes are prescribed by dentists depending on the need of the patient (prescription mouthwashes). These prescriptions are intended for short-term use. However, there are several over-the-counter (OTC) mouthwashes that are freely used by patients without medical supervision. These mouthwashes marketed as a component of daily oral hygiene and is frequently used on a long-term basis.
Some of the common ingredients in a typical mouthwash are:(3)
Solvents (e.g.: water, ethyl alcohol, glycerine, propylene glycol)
Oral health substances - an anticaries compound (e.g.: sodium fluoride, around 217–250 parts per million), arginine, sodium bicarbonate, aluminium lactate, potassium compounds (e.g.: tetrapotassium pyrophosphate), zinc compounds (e.g.: zinc chloride), phosphorus and calcium compounds (eg: tetrapotassium pyrophosphate, hydroxyapatite), stannous compounds: (eg: stannous chloride, stannous fluoride)
Sweetener (e.g.: saccharin)
Surfactant (e.g.: PEG-40 hydrogenated castor oil)
Preservative (e.g.: sodium benzoate)
Some colorant and flavoring agent
Antimicrobial drugs (cetylpyridinium chloride (CPC) or chlorhexidine or hydrogen peroxide or essential oils like menthol).
Therapeutic ingredients: Fluorine compounds like sodium fluoride and stannous fluoride promote remineralization, inhibit bacterial growth and prevent tooth decay. Sodium bicarbonate helps in maintaining acid-base balance in the oral cavity, potentially impacting caries prevention. Zinc compounds like zinc ions and zinc salts prevent plaque formation, reduce halitosis, and promote remineralization. CPCs, chlorhexidine and essential oils derived from plants have antimicrobial properties and are found to be effective in reducing dental plaque and gingivitis. Hydrogen peroxide is shown to reduce gingivitis and tooth staining.
Non-therapeutic ingredients: Ethyl alcohol is used as a polar solvent, solubilizer, stabilizer, flavoring agent, preservative and antiseptic in mouthwashes. Propylene glycol or glycerine is widely used as a substitute for ethyl alcohol in mouthwashes. PEG-40 hydrogenated castor oil serves as an emulsion stabilizer and surfactant, aiding in the solubilization of fragrances and fat-soluble vitamins.
Cosmetic mouthwashes
Cosmetic mouthwashes serve to eliminate oral debris, temporarily combat bad breath, reduce oral bacteria, and leave a refreshing taste in the mouth (no chemical or biological application beyond the temporary benefit).
Therapeutic mouthwashes
Therapeutic mouthwashes offer similar cosmetic benefits along with additional active ingredients like fluoride or chlorhexidine, which protect against various oral diseases like gingivitis, and tooth decay. Mouthwashes containing natural enzymes, cellulose derivatives, and/or animal mucins can replicate the composition and texture of saliva, potentially offering extra relief from xerostomia symptoms.(6) Mouthwashes can sometimes be a combination of cosmetic and therapeutic.
Mouthwashes for preoperative or postoperative management
Povidone iodine mouthwashes are used for decontamination of periodontal sites before invasive procedures. Pre-procedural mouthwashes are used in dental procedures that use aerosol generating equipments including ultrasonic scalers, air polishing, air-water syringes, and tooth polishing with air turbine handpieces or air abrasion. They are known to reduce the microbial (bacteria, virus) load in aerosols. Mouthwashes containing chlorhexidine are effective for lowering the risk of dry socket following wisdom tooth extractions. Mouthwashes containing lidocaine is used to treat mucositis following chemotherapy and radiation treatments for cancer.
Choosing the right mouthwash highly depends on specific oral health needs. Individuals should look for fluorides, chlorhexidine, cetylpyridinium chloride, and essential oils. Ingredients to be avoided are alcohol, artificial sweeteners, sodium lauryl sulfate, and artificial sweeteners.
Dr. Pragati Priya, BDS (PGIMS Rohtak)
To properly use a mouthwash, first of all start by choosing a product according to your oral health needs, whether it's for eliminating foul odor, reducing plaque, or fighting gum problems. Use mouthwash twice a day after brushing and flossing. Take 20 milliliters of mouthwash into a cup, and swish it around your mouth for 30 seconds to 1 minute. After swishing, spit it out, do not swallow. Avoid eating or drinking for at least 30 minutes after using mouthwash to allow it to work properly.
Dr. Pragati Priya, BDS (PGIMS Rohtak)
There is considerable evidence that mouthwashes serve as beneficial adjuncts to conventional oral hygiene regimens like brushing and flossing and aid in reducing dental plaque (is a sticky film of bacteria that constantly forms on your teeth), preventing gingivitis, and tooth decay, and masking bad breath.
Mouthwash complements brushing and flossing by reaching into those places in the oral cavity that cannot be reached by toothbrush and floss. While brushing removes stains and food particles from the teeth and flossing cleans between the teeth and under the gumline, mouthwash can circulate through the entire oral cavity. This way, mouthwash aids in complete cleansing of the oral cavity.
Dr. Pragati Priya, BDS (PGIMS Rohtak)
While there is considerable research on the effectiveness of different mouthwash formulations, conclusive data on their adverse effects is lacking. The reported adverse events include changes in the local oral tissue and teeth morphology alongside functional alterations like taste changes and abnormal oral sensations. Some of the local side effects of the ingredients in mouthwashes are listed below.(5)
Chlorhexidine: Tooth staining, taste alterations, mucosal alterations
Cetylpyridinium chloride (CPC) and essential oils: Tooth staining, oral burning, taste alterations, ulcers, stomatitis
Diclofenac: Oral burning
Triclosan: Taste alterations, mucosal irritations
Fluoride: Mucosal ulcerations, tooth discoloration and staining, paresthesia, altered taste sensations
Delmopinol: Tooth staining, paresthesia, altered taste sensations
OTC mouthwashes, particularly those containing chlorhexidine, may disrupt the oral microbiome, affecting both beneficial and harmful bacteria. Overusing of these antiseptic mouthwashes may also lead to bacterial resistance, highlighting the need for a targeted approach. Literature supports the presence of moderate to severe adverse effects—oral pain, burning sensation, hypersensitivity of the oral mucosa, epithelial desquamation, ulcerations, xerostomia, and petechiae—associated with alcohol-based mouthwashes. Ethanol in them has been implicated in oral and pharyngeal cancers. but consistency and conclusive scientific evidence supporting the ethanol-oral cancer link are lacking.(7)
There are certain instances and individuals where mouthwash is not recommended. Some of them include under-age children to avoid the risk of swallowing it, allergic individuals having allergies to certain components of mouthwash and individuals at high risk of oral cancer, alcohol containing mouthwash must be avoided.
Dr. Pragati Priya, BDS (PGIMS Rohtak)
It is advisable to refrain from strongly recommending the use of mouthwashes in patients with good periodontal health or low caries risk, as they may pose risks such as allergic reactions, oral microbiome dysbiosis, antimicrobial resistance, and implications for systemic health, potentially outweighing any perceived benefits in this group. Similarly, it is not advisable to endorse the use of natural or alternative mouthwashes from health food stores. While many of these products may not have documented harmful effects, there is also insufficient evidence to support their efficacy in alleviating oral diseases.
In addition to their potential local benefits, emerging data, though limited, suggest that mouthwashes may also increase the risk of or exacerbate common systemic disorders. Antimicrobial mouthwashes, especially those containing chlorhexidine (CHX), may negatively impact cardiovascular health by increasing blood pressure through reduced nitric oxide (NO) bioavailability. Using CHX twice daily negates exogenous nitrate-dependent increases in plasma and salivary nitrate and nitrite, leading to elevated BP in both hypertensive and normotensive individuals. This effect is due to the disruption of oral microflora, which are significant modulators of systemic NO bioavailability. The loss of this vasodilator and the subsequent increase in oxidative stress and inflammation can lead to vascular injury and hypertension.(8,9)
Using OTC mouthwash twice daily or more was associated with a 55% increased risk of developing pre-diabetes/diabetes over a three-year follow-up period. Globally, CHX use is not contraindicated during pregnancy, and its use is deemed appropriate when the benefits outweigh the risks. Given the potential link between oral health and preeclampsia, improving oral health in women at risk for this condition may be beneficial. However, evidence regarding the effects of antimicrobial mouthwashes on fetal gestation and periodontitis associated with preeclampsia is currently conflicting.(8)
Combining mouthwashes with mechanical oral cleaning play a significant role in oral hygiene of those with cognitive or motor difficulties. While there's a hypothesis about mouthwashes slowing Alzheimer's disease (AD) progression (presence of similar bacteria in periodontal disease and AD), further studies are needed to establish a definitive cause-and-effect relationship and determine their effectiveness.(8)
The biggest misconception is that it can replace brushing and flossing. However, mouthwash should be used to complement these activities. Apart from this, there's a misconception that more frequent use of mouthwash is good for oral health, but overuse can disrupt the oral cavity’s natural microbiome. Additionally, the burning sensation of alcohol-based mouthwashes is linked with more effectiveness by some individuals, but non-alcoholic mouthwashes can be less irritating and equally beneficial.
Dr. Pragati Priya, BDS (PGIMS Rohtak)
Despite there being numerous mouthwashes and countless components, there is not enough information about many of them. Adding a mouthwash into your oral hygiene routine may improve oral health outcomes, but for optimal results and to avoid adverse effects, it's crucial to seek guidance from a dentist. Dental professionals should recommend mouthwashes that preserve a balanced, healthy, and diverse oral microbiome when treating microbial-induced oral diseases.
References:
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https://www.ada.org/en/resources/ada-library/oral-health-topics/mouthrinse-mouthwash
Vranic E, Lacevic A, Mehmedagic A, Uzunovic A. FORMULATION INGREDIENTS FOR TOOTHPASTES AND MOUTHWASHES. Bosn J Basic Med Sci [Internet]. 2004 [cited 2024 May 2]; 4(4):51–8. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7245492/.
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Tartaglia GM, Tadakamadla SK, Connelly ST, Sforza C, Martín C. Adverse events associated with home use of mouthrinses: a systematic review. Ther Adv Drug Saf [Internet]. 2019 [cited 2024 May 2]; 10:2042098619854881. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6759706/.
Chiam TL, Choo J, Ashar A, Hussaini HM, Rajandram RK, Nordin R. Efficacy of natural enzymes mouthwash: a randomised controlled trial. Clin Oral Invest [Internet]. 2024 [cited 2024 May 2]; 28(5):259. Available from: https://doi.org/10.1007/s00784-024-05658-7.
Gupta V, Pant VA, Pandey S, Pant AB. Efficacy and safety evaluation of alcohol-containing and alcohol-free mouth rinses: A clinicocytological study. J Indian Soc Periodontol [Internet]. 2021 [cited 2024 May 2]; 25(2):128–32. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8041073/.
Alrashdan MS, Leao JC, Doble A, McCullough M, Porter S. The Effects of Antimicrobial Mouthwashes on Systemic Disease: What Is the Evidence? International Dental Journal [Internet]. 2023 [cited 2024 May 20]; 73:S82–8. Available from: https://www.sciencedirect.com/science/article/pii/S0020653923004598
Joshipura K, Muñoz-Torres F, Fernández-Santiago J, Patel RP, Lopez-Candales A. Over-the-counter mouthwash use, nitric oxide and hypertension risk. Blood Pressure [Internet]. 2020 [cited 2024 May 20]; 29(2):103–12. Available from: https://www.tandfonline.com/doi/full/10.1080/08037051.2019.1680270.
