An electric toothbrush is superior to the old-fashioned hand-held variety, right? And a piece of dental floss is your best defence against gum disease and periodontitis, yes?
Your dentist had probably said so … a thousand times. But a new study finds there is insufficient evidence to support these common beliefs. They might be true, but the systemic studies haven’t been done.
A new paper from the University at Buffalo drills down into “the effectiveness of various oral hygiene devices” and found what works best – and what doesn’t.
Short version: wrist-action cleaning is just as good at preventing plaque as those fancy powered toothbrushes that cost 20 to 50 times more.
Overall the paper concludes: “Only a handful of self-administered interventions provide additional protection against gingivitis and periodontitis beyond brushing one’s teeth with a basic toothbrush.”
The findings on brushing probably won’t affect your cleaning habits, but some of the other advice is pretty interesting, and may seem contradictory. The New Daily has provided qualifying information independent of the Buffalo study.
What’s been proven to work?
The basic wrist-action toothbrush: Often found in a drinking glass on the bathroom bench. Not fancy enough for you? It does an equally good job at reducing plaque when compared to plug-in technology.
Interdental brush: these are the brushes that look like tiny bottle-washers, used to clean between the teeth. Effective at reducing gingivitis.
Water pick, also known as a water flosser or oral irrigator: works by spraying lukewarm water between your teeth. Can be messy but, along with interdental brushes, does a superior job of reducing gingivitis.
Science editor’s note: Some dentists hate mouthwashes. They feel they’re a waste of time and bestow a false sense of security among people who believe they can take the place of brushing. They cannot. We have included links to advice from nps.org.au (National Prescribing Service) independent of the Buffalo researchers.
Chlorhexidine gluconate (CHX): Recognised as the most effective mouthwash for reducing plaque and gingivitis. Tends to require a prescription in the US. In Australia, the advice is vague. According to healthdirect.gov.au: “We are unable to tell you if you need a prescription for this medicine. You can ask your pharmacist.This medicine is Not Scheduled.”
Twice-daily chlorhexidine should 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 halitosis. It is not recommended for long-term use due to its numerous adverse effects.
These include tooth and restoration staining, soft tissue staining, increased calculus deposition, unpleasant taste, taste alteration, burning sensation, desquamation and mucosal irritation.
Cetylpyridinium chloride (CPC): Clinical studies have shown that mouthwashes with these ingredients significantly lower plaque weight and reduce gingival inflammation. (However, other studies have yielded contradictory results showing that some of these products are no better than a placebo or water rinse in reducing plaque and gingivitis scores.)
Essential oil (Listerine) mouth rinses: Contains eucalyptol, menthol, methyl salicylate, and thymol, claimed to be identical to oils found naturally in eucalyptus trees, corn mint, thyme and wintergreen. Except for Listerine Zero, the varieties contain alcohol, enough to get drunk on. Shown to reduce plaque and gingivitis.
Bad stuff best avoided: Triclosan
Triclosan toothpastes and mouth rinses significantly reduced plaque and gingivitis, however, as the Buffalo authors write, “the compound is linked to the development of various types of cancers and reproductive defects”. Triclosan has been removed from most popular toothpastes in the US.
In Australia, according to the Cancer Council, the use of triclosan in cosmetics is limited to a maximum concentration of 0.3 per cent.
In May 2009, triclosan was the subject of a full risk assessment by the National Industrial Chemicals Notification and Assessment Scheme (NICNAS) within the Department of Health.
The report concluded that, “under normal conditions of consumer use, the risk of adults and children being exposed to levels of triclosan that would lead to chronic health effects is low”.
In August 2014 there was a worldwide media focus on the use of triclosan in Colgate Total toothpaste, with some articles drawing a link between the ingredient and cancer.
Some Australian manufacturers have voluntarily chosen to remove triclosan from their products following the ban in the US.
The as-yet unproven claims
Electric-powered toothbrushes are no more effective at reducing plaque and gingivitis than a basic toothbrush, found the researchers. They’ll do the job and will save your wrist somewhat from hard labour, but maybe not much.
Little evidence has been published in support of dental floss as a tool to reduce plaque and gingivitis. Still, the researchers recognise floss as “the mainstay of interdental cleaning”. They urge you not to “toss your floss just yet”.
“While there are few studies available that specifically examined toothbrushes or floss alone, both are still essential,” said Dr Frank Scannapieco, principal investigator and chair and professor of oral biology at Buffalo’s School of Dental Medicine.
“Floss is especially useful to remove interdental plaque for people who have tight space between their teeth. Floss also likely reduces the risk for cavities that form between the teeth.”
The investigators found insufficient evidence that mouthwashes based on tea tree oil, green tea, anti-inflammatory agents, hydrogen peroxide, sodium benzoate, stannous fluoride, hexetidine or delmopinol reduced gingivitis.
They advised that the use of probiotics, “although promising as a preventive strategy against gum disease, is unproven”.
The researchers found little evidence that supports the claim that dietary supplements improve gum health.
The investigators, perhaps somewhat controversially, also found insufficient evidence that professional plaque removal – known as scaling, the process of removing plaque with a scraper – prevents gum disease.
No doubt there’ll be dentists saying “pull the other one”.