A Symmetrically Designed Cylindrical Oral Irrigator Perfect for Sanitary Spaces

Oral Irrigator EW-DJ71

Concern with oral care has steadily risen in recent years, as recent research makes clear the relationship between periodontal disease and systemic disease. Yet Panasonic's Oral Irrigator retained the same design from 20 years ago. The development team members set out to push on this heavy door to open up the market with better performance and a contemporary design.

TALK 1: Designing the World of Oral Irrigator
A Symmetrically Designed Cylindrical Oral Irrigator Perfect for Sanitary Spaces

The common concept: "Professional and clean"

The DJ71's cylindrical shape is strikingly novel compared to the old model. What was the aim behind this?

Mitsuyasu: The previous model had had a very long run, making it look familiar but no longer new. The square-shaped tank looks old-fashioned and was ridiculed by being likened to an aquarium. We had to ensure that the product's image conformed to the unified worldview of electric toothbrushes to expand the Oral Irrigator lineup.

Bessho: The Battery typed electric toothbrush, which became a hit in Japan in 2010, gave a beauty care image to Panasonic's oral care products. As that gradually faded, the time came to act. We accurately defined the goal of our business to be periodontal care, while the Oral Irrigator concept became "professional and clean," incorporating clinical elements intrinsic to oral care.

Mitsuyasu: The penetration rate of oral irrigators in Japan is just 1%. It's not the sort of product you can test out in a store, so we totally revamped the design to lift its recognition and get people interested in it.

Bessho: We wanted to change the idea that only people with serious oral problems would use it. Our intention with this design is to make it part of people's everyday lives. The symmetrical cylinder suggests functionality. So for example the handle is a magnetic type that enhances usability, and the curl hose retracts fully inside the device. Points like these give it a sense of cleanliness and hygiene essential to a sanitary product.

Mitsuyasu: I still remember vividly the amazement of seeing the first mock-up of the cylindrical model. I was so happy to see how far beyond my expectations it went. But a lot of people worried that the design was too much of a change.

Bessho: The initial sketches had a lot of variations. We chose the cylindrical shape after comparing it with square and oval ones.

Mitsuyasu: I felt relieved to see our ideas proved right when it became a hit product.

The reviews were beyond what we anticipated, generating more and more interest

The YouTube video FLORAL PLATE^* went viral with over 2.5 million views. What reactions in particular impressed you after it went on sale?

Mitsuyasu: We were amazed by the sensation sparked by the lovely floral plates in the video. Our aim was simply to get younger people watching, but we got a greater response than expected from around the world, including requests for borrowing that plate for events and so on.

^*This video is no longer available.

Bessho: I think it's quite rare for a product to be successful at all four of the world's main design awards (Red Dot, Good Design, iF, and the Chinese Appliance & Electronics World Expo). Its user-friendliness was praised in Europe, while in China there's a lot of interest in oral irrigation care. Success at these four awards has lifted recognition for oral irrigators.

Mitsuyasu: The reaction in Japan was spectacular too. Some well-timed TV shows on oral irrigators right after the release of the DJ71 led to it selling out in a flash. Some of the online reviews used really unique expressions, like saying that "there was a smell like a crayfish had crawled out of my mouth." The media got hold of that and produced an illustration showing a crayfish flying out of a mouth, which sparked even more buzz. Though I'm fairly sure Oral Irrigator won't really make any crayfish come out of your mouth (laugh).

Bessho: We hold talks with dentists in order to realize the "professional and clean" concept. The information we gather gives us ideas on how this tool should be used to maintain oral cleanliness.

Mitsuyasu: More and more people are getting their teeth straightened these days. I wore braces when I was a child. Food often got trapped in them, making it very hard to keep them clean. It was with that in mind that we showed the DJ71 washing away particles trapped in braces in a product promotional video.

Bessho: The ease of daily use is a key point. We need to make it more user-friendly and improve the design so that it fits into people's everyday lives to encourage them to start oral care. We also want to expand the lineup to offer customers more choices.

TALK 2: Adding New Value to the Product
Taking it to the Global Market! The DJ71 Is Setting a New Look for Oral Care

Dealing with such a complete overhaul wasn't easy

As the developers of the product, what part do you feel strongly about?

Taniguchi: I was in charge of designing the nozzle. The shape was the key factor. While knocking ideas about with R&D in the planning stage, I started thinking about cavitation jets. This technology had been researched for quite a while, but the commercialization had not yet been achieved due to the lack of stability of the tiny bubbles. We got some information from the fine bubble industry and gradually worked out the characteristics.

Hoshino: For me it was the pump block on the very bottom of the device. A rounded design generates dead spaces, plus there are limits on the height of the motor. It was tough work to get a pressure-generating pump into that space.

Kuwayama: The job of the circuits I developed was to keep that pump as stable as possible. The water pressure button is located at the top, so we placed two boards in a T shape. The key point here is global compatibility. We built a compact circuit to change the voltage depending on the country of use.

Yamasaki: The DJ71 is manufactured by Panasonic Wanbao Appliances Beauty and Living (Guangzhou) Co., Ltd. in China. It was a hard task for the plant to deal with all the new design elements, and ensure the stable assembly and quality conformance of all products. The curved nozzle, for example, contains a metal pipe. The precision of that directly affects the stability of the water flow. It's also quite complex to waterproof a cylindrical shape. We conducted an exhaustive assessment through a water flow test for all nozzles and a waterproof test using equipment created for a four-grade inspection of all products.

Hoshino: The design around the tank proved the most troublesome for manufacturing. It was hard in terms of construction to maintain the intended shape, as there would always be gaps between the tank and the housing. There's a limited control range for the temperature and speed to mold the plastic, making it hard to manage.

Yamasaki: The manufacturing staff kept up quite a bit of pressure on Hoshino in a strained atmosphere. We overhauled the dies and tried various approaches, spending a month on fixing irregularities, but we finally got it right.

Kuwayama: I never saw Hoshino in person in Japan in the last part of the development period (laugh). He was always on the other side of the screen via videoconferences from China.

The high praise from the customers spurred our professional spirit

Please tell us what you thought during the development process, what you feel right now, and your visions for the future.

Taniguchi: The old model's design looked outdated even to me, but it has now been fully transformed. Cavitation jets will differentiate us from our competitors. This was a very rewarding development. Users may feel that the water pressure is lower than the previous model, but it was great to hear customers remark that they like the feeling of the new model's water flow.

Yamasaki: For us here at the plant, it's also great to hear that customers appreciate the value of what we have created. Although the manufacturing frontlines faced their busiest time in the first six months after starting mass production, hearing that it had become a hit in the marketplace really motivated us.

Kuwayama: I personally used the old model from prior to this development project, but because of the dated look of the design I kept it hidden in a cupboard. So from the point of view of a customer I knew I wanted to start using this new design at home as soon as possible.

Hoshino: We decided on this form for the overseas markets. Our rival products overseas all have the same square look lined up on the display counters. With our lower presence overseas, we'd never get anywhere with another square design. Repeated market surveys showed that this cylindrical look is the one to go for. We chose to be specific about the type of plastic used for the tank because we know that dishwashers are quite common overseas.

Yamasaki: Fully convinced by the plan, our manufacturing team did its best. The world-class specifications presented by the design were very persuasive. We wouldn't be so accommodating if the plan was not worth our effort to think about (laugh).

Kuwayama: The reaction at trade shows was impressive. Especially from people from other countries. First, they'd show interest in the cylindrical shape. They'd be amazed when we told them it was a device to clean your mouth, then they'd listen to what we had to say. I'm sure this product will sell more than in Japan.

Taniguchi: I certainly hope it does do well overseas. We have to raise recognition in Japan, and beat our rivals internationally! There's still more work to be done on the water flow technology. We achieved even better cavitation jets with the handy model released after the DJ71. This should serve as a starting point to build up our technology and apply it to the creation of even better products.

TALK 3: Our Mission
The Goal Is to Provide a Solution to Periodontal Disease, the World's Most Common Health Problem

In 2013, when I first started working in planning for oral care products, electric toothbrushes made up 90% of Panasonic's sales of oral care products in Japan, oral irrigators were outliers. We started working on the DJ71 in 2015. Now oral irrigators have risen to make up 30% of Panasonic's oral care product sales. As these figures show, DJ71 played a significant role in making those involved in this business at Panasonic aware of the potential of oral irrigators.

At first opinions were split as to the merits of the cylindrical design. We refined the design through multiple acceptance surveys in Japan and abroad. The design was validated by the fact that 90% of the respondents liked it. One particular comment on the day of a survey really stuck with me. "If you put this on sale, I'm definitely buying one!" That's something I don't forget. Many people said of our previous model oral irrigator that they were very satisfied with its performance, but hoped something could be done about the design.

I want to do something about periodontal disease, because it's the world's most common health problem. That's my own basic hope and the goal behind our business. Eighty percent of Japanese people suffer from this disease. We have a mission to try and do something to minimize the suffering of so many people. The penetration rate of oral irrigators is still at just 1%, with only a 10% recognition rate.

With the DJ71 we achieved the goal of improving gum health after around one week of use, but we're now looking to improve that to three days. We want to boost its performance and the penetration rate. We will strengthen our lineup based on the DJ71, which offered new value.

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