A Billion Plastic Toothbrushes Hit Landfills Every Year: Silicone Could Be The Fix

Every three to four months, Americans are supposed to throw out their toothbrush and buy a new one. Most do. That adds up to roughly one billion plastic toothbrushes hitting U.S. landfills each year. That figure doesn’t account for the billions of people in lower-income countries who can’t afford to replace a brush that often, or who lack reliable access to clean water. A new review published in PLOS Global Public Health argues that a softer, longer-lasting alternative has been quietly sitting in the dental care aisle: the silicone toothbrush.

Researchers from McMaster University, the University of Waterloo, Dalhousie University, and the University of Cincinnati searched five major scientific databases and turned up just ten studies ever published on silicone toothbrushes. That number signals how little attention this material has received in oral care.

The limited research that exists paints a cautiously encouraging picture. In specific designs and populations tested, silicone toothbrushes appear to clean teeth about as well as conventional ones, may be gentler on gums (mainly in lab and animal studies), and one lab study found similar performance with or without water. Based on a single environmental assessment, they may also carry a smaller ecological footprint. Results don’t apply uniformly across all silicone brush designs or all users.

That combination of potential traits could matter most in low- and middle-income countries, where oral disease hits hardest. Over 3.5 billion people worldwide are affected by oral diseases, the most common non-communicable diseases on the planet.

How Researchers Mapped the Silicone Toothbrush Evidence

Led by Aoife Cummins and Alexa Bennett, the team conducted a scoping review to map all available research on the topic. Those ten studies broke down into lab experiments, clinical trials with human and animal participants, and one environmental impact assessment, covering populations from children as young as five through adults up to 75 in Brazil, India, Italy, and Turkey. One study used beagle dogs. Comparison groups typically involved standard plastic-and-nylon toothbrushes, though one study pitted a silicone finger brush against the common practice of cleaning teeth with a bare finger.

Silicone Toothbrushes Cleaned Well and Were Kinder to Gums

On the central question of whether silicone brushes actually clean teeth, the answer was generally yes, with caveats. Two studies found comparable plaque removal to conventional nylon-bristle brushes: one involving college-age volunteers in Brazil, the other looking at children ages five to seven brushing independently and with parental help.

In India, silicone finger brushes outperformed bare-finger cleaning among adults who normally used that method, pointing to a meaningful improvement at low cost for communities where a traditional toothbrush is not the norm.

Not every result favored silicone. A study from Italy testing a U-shaped electric toothbrush with silicone bristles found it essentially no better than not brushing at all. Researchers attributed this to the device’s short bristles, which likely failed to reach tooth and gum surfaces. That points to a design flaw, not a problem with silicone itself.

Two lab-based studies refined a silicone mouth swab for older adults, finding that a specific firmness level optimized plaque removal and that longer, textured bristles improved performance. Those studies also found no meaningful difference in cleaning with or without water, a result worth noting for regions where clean water is scarce.

Across multiple studies, silicone toothbrushes showed a lower risk of injuring gum tissue or wearing down tooth surfaces compared to nylon bristles. In the beagle dog study, sonic toothbrushes with warmed silicone bristles produced the highest level of gum cell growth compared to nylon-bristle brushes. Because several of these results come from lab or animal models, they can’t be taken as direct evidence of what would happen in everyday human brushing.

Silicone’s gentleness could benefit people with sensitive mouths, including young children, older adults, and those with limited hand control. One study concluded that a silicone brush might suit kids under nine better than a conventional one, since children that age typically lack the fine motor skills needed for effective brushing.

A Greener Brush, but the Data Are Early

Only one study in the review tackled the environmental question, so findings here are especially preliminary. That life cycle assessment compared six toothbrushes and found silicone-bristle brushes outperformed nylon-bristle brushes across all 18 environmental impact categories, with an average reduction of 14 percent. Silicone may also have advantages in durability and reuse compared to conventional plastics.

For communities in lower-resource settings, the short lifespan of a plastic toothbrush creates what the researchers describe as an unsustainable dependence on outside supply chains and donations. A durable, sterilizable silicone toothbrush that cleans without water could, the authors suggest, help disrupt that cycle. Any new tool must be designed with input from the communities that would use it, respecting local customs and practical realities rather than assuming a one-size-fits-all solution.

With only ten studies spanning more than two decades, the most pointed message from this review is that silicone toothbrushes remain woefully unexplored. Early results are encouraging within the specific contexts studied, and the need is undeniable. What’s missing is the investment to find out whether this tool can deliver at scale.

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