From Bristles to Motors
People cleaned their teeth long before the toothbrush as we know it. Chew sticks were used in many ancient cultures, and bristle brushes with handles of bone or wood were being made in China by about the fifteenth century and spread through Europe over the following centuries. Nylon bristles replaced animal hair in the late 1930s. Those facts set up the question that the electric toothbrush answered: could a motor do the scrubbing movement?
This is a history of the product only. It is not dental advice, and anyone with questions about brushing should ask a dentist.
The Early Models, 1950s
The electric toothbrush is usually linked to Switzerland in the 1950s, where a physician, Philippe-Guy Woog, is often credited with developing an early powered brush, reportedly with patients who had difficulty brushing in mind. Exact dates differ between sources, and some accounts suggest similar devices were being tried in more than one place.
What is better documented is the American launch. A plug-in brush was introduced in the United States around 1959, marketed to dentists and the public by the pharmaceutical company Squibb. It had a handle containing an electric motor and a cord that plugged into a wall socket, with a head that moved in a back-and-forth motion. Because it ran from mains electricity near a sink, it relied on insulated design, and the cord was one of its main drawbacks.
Cordless and Rechargeable Brushes
The next logical step was to remove the cord. General Electric introduced a cordless rechargeable brush in the early 1960s. It used a nickel-cadmium battery sealed into the handle, which was recharged by placing it on a charging stand without a metal electrical connection, using electromagnetic induction. That arrangement is the same idea used by many modern chargers. Sealing the handle also meant the brush could be used in a wet bathroom with less risk.
These models were novelties for many years. They were more expensive than a manual brush, and the battery technology was heavy and limited. Interest was moderate, and adoption grew slowly.
Rotating and Oscillating Heads
During the 1980s and 1990s, designs changed. Instead of a head that moved back and forth along a line, some brushes were built with a small round head that rotated in one direction and then the other. This oscillating-rotating motion became a common format, and rechargeable models with timers, which signaled when a set period had passed, became more common. Different manufacturers offered pressure sensors and interchangeable heads. As with many consumer products, design competition drove many of these features.
Sonic and Ultrasonic Brushes
In the early 1990s a different approach appeared: brush heads that vibrate at high frequency, producing sound-wave range vibrations rather than visible sweeping movement. The first widely sold model of this type, a “sonic” brush, was introduced in 1992 by a US company. Its marketing claimed that the vibrations affect the fluid around the bristles as well as the bristles themselves. Ultrasonic models, vibrating at still higher frequencies, appeared later. Claims about the relative effectiveness of different types vary, and reviews of the research generally describe the differences as modest, so this article does not rank them.
Batteries and Motors Inside the Handle
The progress of the electric toothbrush mirrors that of its parts:
- Motors: small direct current motors, descendants of the early industrial machines, were refined and made quieter.
- Batteries: nickel-cadmium gave way to nickel-metal hydride and then to lithium-ion batteries, which are lighter and hold a charge longer.
- Electronics: timers, speed settings and, later, wireless links to smartphones were added.
Cheaper Battery-Powered Brushes
A different branch of the product appeared in the 2000s: low-cost brushes powered by a replaceable AA or AAA battery, sold in supermarkets and drugstores. These made powered brushing available at a price close to that of a manual one, though they tend to be less powerful than rechargeable types.
Costs, Waste and Design
Powered brushes raise some practical questions. Replacement heads create plastic waste, batteries sealed into handles complicate recycling, and some products have been criticized for apps and accessories that add cost. Manufacturers have responded in different ways, for example with recyclable packaging or handles designed to last for years.
A Long Evolution
The electric toothbrush did not have one moment of invention. A Swiss prototype in the 1950s, an American mains-powered launch in 1959, a cordless rechargeable model in the early 1960s, and sonic designs in the 1990s are the milestones most often cited, with dates that differ slightly in different sources. Its history is an example of how an existing idea (the brush) was changed by smaller motors and better batteries.