By Natasha Khan | Photographs by Evan Angelastro for WSJ

Eduardo Jiménez has thousands of toothbrushes. He compliments strangers on their smiles, then asks them about their dental regime. Family and friends know not to get him started about their oral habits because he may not stop.

At work he really obsesses. Jiménez, director of technology at Colgate-Palmolive, carries buckets of toothbrushes to meetings. He studies the angle of bristles and their corresponding scrubbiness. He pores over data from focus groups about the width of the handle and the all-important gripping point where a user's thumb and fingers hold the brush. Sometimes he brushes at his desk.

He is on a mission that has eluded Big Toothbrush for years: the two-minute clean.

That is the amount of time dentists say it takes, twice a day, for adequate plaque removal. The problem is people tend to fall way short -- focus groups show that even people who say they brush for two minutes actually do so for about 45 seconds.

It is a challenge that has baffled dentists and other oral-care zealots for years, and spawned a whole category of tricks -- from annoying children's songs to brushing timers -- aimed at getting people to spend more time on their teeth.

Designers at companies like Colgate and Procter & Gamble have been trying to close that gap by making a device that makes brushing feel like less of a chore -- and compensates for poor effort and technique.

"We have an evergreen goal: how can we design a toothbrush that can clean well no matter how you brush?" he said. "We want the brushing experience to be meaningful and different."

Jiménez, 60, has been at it for 23 years. If you've ever used a Colgate toothbrush, chances are he had a hand in designing it. He has 239 patents, most of them toothbrush-related.

Over the years, he's observed some trends. Blue is the most popular toothbrush color. Some people don't brush on weekends. Even though dental hygienists recommend smaller brush heads, Americans usually choose the biggest one. And they're always after something new.

His latest project is based on a conclusion that young adults are looking for more minimalist designs and a more soothing experience.

For the first time since he joined the company, Jiménez enlisted toothpaste chemists at Colgate to work with his team on a toothbrush-toothpaste combo designed to make brushing feel more like a spa treatment.

They created multiple brush head prototypes and ran them through a robotic tool called a Robocheck that measures the degree of cleaning efficacy before being tested by humans. They settled on a head with more than 5,000 high-density skinny bristles that combine with the toothpaste to form small bubbles, creating a sensation Jiménez compares to a "bubble bath for your mouth."

Holding up Colgate's latest creation, Jiménez showed off what he described as a mountainous head with an ideal combination of soft, stiff, short and tall bristles that hugs each tooth and reaches everywhere from the gumline to the enamel.

Jiménez said he operates on the assumption that many people won't brush for two minutes no matter what the brush looks or feels like. In fact, to meet the elusive goal himself at night he uses an electric toothbrush with a timer.

"It's very hard to get people to be compliant with home care unless they really love their teeth," said Jennifer Connolly, a New York-based dental hygienist.

"In my office, many patients will commit to brushing and flossing and staying the course," Connolly said. "But then they do it for a week or so and fall off."

At P&G in Cincinnati, Ohio, researchers years ago concluded that the clearest path to the two-minute clean was an electric device that lets people know how long they've been brushing. One challenge was getting people to switch over from manual, so the latest model was designed in part to eliminate those barriers.

Sherrie Kinderdine, director of research and development at the company's oral care unit, said she spent hours with consumers, shopping with them and sometimes going into their homes and watching them brush. One conclusion: people typically don't put much thought into brushing.

"People tell me brushing their teeth is like putting on their socks," Kinderdine said.

One of her observations was people were using their toothbrushes in the guest bathroom because they didn't want the noise to disturb other family members, so the new brushes are quieter. Bathroom design and aesthetics matter more and more, so the matte coating on the device is meant to be more sleek.

Another observation: People brush too hard. The company's brushes have pressure sensors that automatically light up red when the brusher needs to slow down.

Toothbrushes as we recognize them -- with a handle and 90-degree bristles -- were first used in China in the late 1400s. For centuries they were primarily made with bone handles and boar bristles and their use in America was limited mostly to the wealthy.

Toothbrushes in the U.S. became more widespread after the discovery of nylon and Lucite, which American manufacturers used to make their own. That innovation coincided with a push by the U.S. military for soldiers to have better oral hygiene, including a requirement that they have a certain number of teeth to be eligible for service, according to Scott Swank, a dentist who's also the curator at the National Museum of Dentistry in Maryland.

After the war, motion pictures began soaring in popularity, along with celebrities with sparkly white teeth like actress Farah Fawcett's. That heralded an era of oral care advertising from companies like Colgate and Crest, which is now also owned by P&G.

The U.S. toothbrush and dental accessories market had $4.68 billion in sales for the latest year through January 2025, according to Circana, a Chicago-based market research firm.

When Jiménez needs inspiration, he draws it from Colgate's toothbrush archive at the company's Piscataway, N.J. campus. It's a collection he started of thousands of toothbrushes, some centuries old, many of which he bid for on eBay.

The next personal frontier for Jiménez is a toothbrush that can replace flossing.

Write to Natasha Khan at natasha.khan@wsj.com

(END) Dow Jones Newswires

February 17, 2025 05:30 ET (10:30 GMT)

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