Mouthwash

Mouthwash

• A mouthwash may be recommended to treat infection, reduce inflammation, relieve pain, reduce bad breath or to deliver fluoride locally for caries prevention
• Recommending particular mouthwashes should take into consideration the patient’s ability to perform good oral hygiene practices (tooth brushing and dental flossing), the condition of their teeth, gingivae and oral mucosa, their risk of oral disease (for example, presence of xerostomia), and the proven efficacy of the mouthwash and its potential adverse effects

There are many mouthwash options available – this summary provides information on the ones that are commonly available:

Chlorhexidine

• Chlorhexidine gluconate is a broad spectrum antimicrobial activity
• It is currently the most effective mouthwash for reducing plaque and gingivitis
• Use of chlorhexidine is not associated with development of resistant organisms
• As chlorhexidine may interact with fluoride and sodium lauryl sulfate (a detergent found in toothpastes), it should be used after rinsing with water
• Current recommendations are for twice-daily chlorhexidine to be used only as a short-term adjunct, or as an aid in disinfection of surgical sites, to improve wound healing, or as a short-term treatment of bad breath
• It is not recommended for long-term use due to its numerous adverse effects

Mouthwash with essential oils

• Mouthwashes containing four phenol-related essential oils (thymol, eucalyptol, menthol and methyl salicylate in up to 26% alcohol) claim to penetrate the plaque biofilm and thus kill micro-organisms that cause gingivitis
• These mouthwashes display broad spectrum antimicrobial activity, prevent bacterial aggregation, slow bacterial multiplication, retard plaque maturation and decrease plaque mass and pathogenicity
• Their mechanism of action is thought to involve bacterial cell destruction, bacterial enzyme inhibition and extraction of endotoxin from Gram-negative bacteria
• They also have anti-inflammatory and prostaglandin synthetase inhibitory activity and act as antioxidants by scavenging free oxygen radicals
• Clinical studies have concluded that essential oils are effective in reducing plaque, gingivitis and halitosis due to their bactericidal and plaque-permeating abilities
• Mouthwashes containing essential oils have been recommended as an adjunct to mechanical oral hygiene, particularly in patients who have impaired oral hygiene and those who suffer from gingival inflammation despite regular brushing and flossing
• These mouthwashes can help support gingival health around dental implants
• They are not recommended for patients suffering from xerostomia, dental erosion due to a low oral pH, or oral mucosal disease due to possible ethanol-induced mucosal irritation and dryness
• These mouthwashes are unsuitable for children due to the risk of accidental ingestion of high doses of alcohol

Cetylpyridinium chloride, sodium benzoate and triclosan mouthwash

• Cetylpyridinium chloride is a compound with antiseptic and antimicrobial properties
• It binds to bacterial surfaces causing disruption
• Mouthwashes containing cetylpyridinium chloride inhibit and reduce plaque build-up
• Those containing sodium benzoate as the active ingredient are thought to act by dispersing fatty, proteinaceous and carbohydrate substances
• This weakens plaque attachment and aggregation making it easier to remove during tooth brushing
• Triclosan is used to increase the ability of mouthwashes to bind to the oral mucosa and thus be available for longer periods of time
• Clinical studies have shown that mouthwashes with these ingredients significantly lower plaque weight and reduce gingival inflammation

Oxygenating agents – hydrogen peroxide

• Hydrogen peroxide has been used to relieve minor gingivitis because of its oxygenating cleansing action
• It is also used to relieve soreness caused by dentures, orthodontic appliances and following dental procedures
• Hydrogen peroxide is a bleaching agent with strong oxidising properties and some products also contain ethanol as an antimicrobial, preservative and solvent
• All these products act by liberating oxygen to loosen debris, remove light stains and kill anaerobes
• They are also broad spectrum antimicrobials and have been shown to reduce gingivitis and staining
• Oxygenating mouthwashes have been recommended for the treatment of acute ulcerative disease, to reduce gingival inflammation
• They can also be used for stain removal and as a soaking solution for dentures

Povidone-iodine containing mouthwashes – Betadine mouthwash

• Povidone-iodine has a broad spectrum of activity against bacteria, fungi, protozoa and viruses
• The mouthwash has been shown to be effective in reducing plaque and gingivitis and may be a useful adjunct to routine oral hygiene
• It also reduces the incidence, severity and duration of radiation mucositis
• Absorption of excess iodine has been postulated to result in metabolic complications, however this is not of concern in patients without pre-existing thyroid disease and if the patient spits out the solution

Fluoride-containing mouthwashes

• Fluoride assists in the prevention of dental caries by promoting remineralisation thereby increasing enamel resistance to acid attack
• Fluoride is available in different concentrations as either acidulated phosphate fluoride or sodium fluoride
• Fluoride mouthwashes reduce dental caries and they are recommended for patients at high risk of dental caries including those with xerostomia after irradiation and chemotherapy, those who have difficulty with oral hygiene procedures and those undergoing fixed orthodontic treatment
• Fluoride mouthwashes are not indicated in children younger than six years of age as the risk of ingestion is high

Biotene mouthwash

• Biothene is a dental hygiene product which comes in a number of forms, including toothpaste, mouthwash and cream
• In addition to the active ingredient sodium monofluorophosphate in its toothpastes, all the products contain enzymes including glucose oxidase, lactoferrin, lactoperoxidase and lysozyme – the PBF (plaque biofilm) products also contain the enzymes mutanase and dextranase
• Patients with xerostomia (dry mouth) may use Biotene to reduce the rate of recurrence of dental plaque –  however, Biotene by itself does not significantly reduce the count of Streptococcus mutans which is the primary initiator of the formation of dental plaque
• Biotene products may not be suitable for those with acid reflux (GORD) as many of the Biotene products contain peppermint oil which may worsen reflux symptoms

Sodium bicarbonate

• A mouthwash can be prepared by dissolving one teaspoon of sodium bicarbonate in a glass of water
• It is recommended in patients suffering from xerostomia or erosion due to its ability to increase salivary pH and suppress the growth of aciduric micro-organisms such as Streptococcus mutans
• Sodium bicarbonate can improve taste and it neutralises acids and thus prevents erosion
• It is bland and will not irritate the oral mucosa in patients with xerostomia or oral ulcerative disease
• Sodium bicarbonate mouthwashes can be safely used in the long-term

Listerine

• The active ingredients listed on Listerine bottles are menthol, thymol, methyl salicylate, and eucalyptol
• In combination all have an antiseptic effect and there is some thought that methyl salicylate may have an anti inflammatory effect as well
• Alcohol (ethanol) which is toxic to bacteria at concentrations of 40%, is present in concentrations of 21.6% in the flavoured product and 26.9% in the original gold Listerine Antiseptic

Alcohol in mouthwash – mouthwash and cancer

• Ethanol in mouthwashes is used as a solvent, preservative and antiseptic
• It causes protein denaturation and lipid dissolution, so it has antimicrobial activity against most bacteria, fungi and viruses
• Studies have shown that high concentrations of alcohol (above 20%) in mouthwashes may have detrimental oral effects such as epithelial detachment, keratosis, mucosal ulceration, gingivitis, petechiae and pain
• There is increasing evidence that there may be a direct relationship between the alcohol content of mouthwashes and the development of oral cancer
• The risk of acquiring cancer (oral cavity, pharynx, larynx) is increased by over nine times in smokers and over five times in those who also drink alcohol
• A recent review of the literature suggested that it would be inadvisable to recommend the long-term use of alcohol-containing mouthwashes

Conclusion

• Patients, dentists and doctors are faced with a multitude of mouthwash products containing many different active and inactive ingredients
• Making informed decisions as to the suitability of a particular product for a particular patient can be a complex task
• Although many popular mouthwashes may help to control dental plaque and gingivitis, they should only be used for a short time and only as an adjunct to other oral hygiene measures such as brushing and flossing
• Long-term use of ethanol-containing mouthwashes should be discouraged given recent evidence of a possible link with oral cancer
• Fluoride mouthwashes should be encouraged in patients with a high risk of caries