BOSTON — Granted, nothing is likely to make going to the dentist fun. But a leading product development firm has employed the design flexibility of RIM polyurethane to help one dental-equipment supplier take some of the sting out of the experience.
And last week those responsible reaped some glory for their collaborative efforts by being chosen winner of the second annual IDSA/Plastics News Design Award at the Structural Plastics '99 conference, held April 18-20 in Boston.
Midwest Dental Products Corp., a Des Plaines, Ill.-based division of Dentsply International in York, Pa., in August 1996 hired IDEO Product Development to completely redesign the steel-clad desktop device Dentsply used for applying its air-abrasion process.
Dentists use air abrasion, a half-century-old process that is experiencing a resurgence now, to prepare patients' teeth for filling cavities, applying sealants, removing stains and repairing fillings. The process delivers aluminum oxide particles with pressurized air through a hose, often eliminating the need for dentists to jab your gums to inject a local anesthetic and to use their nasty little drills. A hose and small suction unit captures and evacuates the used particles from the patient's mouth.
After much research IDEO, in turn, selected Premold Corp., a small processor in Oconomowoc, Wis., to help it develop and manufacture the product's six enclosure panels from PU, using the reaction injection molding process. And Premold ended up drafting two Wisconsin toolmakers into the project — Mantz Automation Inc. to make five aluminum molds, and Precision Pattern Inc. to produce an epoxy mold for making the largest, vertical panel.
This aggressive exercise in concurrent engineering — involving an IDEO team of nearly a dozen designers and engineers stretching from its Palo Alto, Calif., headquarters to its office in London — eventually produced what Midwest Dental dubbed its AirTouch Cavity Detection and Treatment System.
The product, available in a wheeled, tower version as well as a desktop model, began making its way into dentists' offices early last year. By all accounts, the project's attempt to marry form with function, and produce a friendly design that will seem less intimidating to patients, has succeeded.
Last week's award to IDEO, sponsored jointly by Plastics News and the Materials & Processes Section of the Industrial Designers Society of America, is the latest in a string of four design awards captured by the AirTouch product, including one honor from Germany, the Essen Red Dot Design Award. It also will be a finalist in the competition at the upcoming Medical Design & Manufacturing East show in New York.
A three-person jury selected the IDSA/PN award winner from a strong, diverse field of 76 eligible entries. The judges said they liked such features as the AirTouch's ``user interface—how the handle blends into the top,'' and the design of the floor unit, which is very balanced and easy to roll around.
Judge Robert D. Russell, a Xerox Corp. technical specialist, said that if Dentsply had planned to make 100,000 units of the product a year, he would have suggested gas-assisted injection molding for the panels. But for its low production volumes, he thought the process used was appropriate.
John Brassil, who managed the project from IDEO's Evanston, Ill., office, said the the parties involved determined fairly early that RIM was the best process for the three panels that form the top portion of the AirTouch unit. He said Premold's success in that part of the project and its insistence that it could also use RIM for the larger, lower panels convinced IDEO to give it a try.
The team designed for production volumes of ``a couple thousand a year,'' Brassil said in an April 21 telephone interview. The most feature-rich units retail for $7,500 for the desktop model and $16,995 for the rolling floor model, according to a Midwest Dental spokeswoman. The latter contains within its vertical, hollow body the space needed for the unit's vacuum pumps, electric motor and plumbing.
Each floor model contains about 40 pounds of PU material, Ken Schweitz, Premold president and owner, said in an April 20 interview at the Boston meeting.
Five of the AirTouch panels are molded from Bayer Corp.'s Prism CM-200 solid PU RIM system. The largest vertical panel is made from Carpenter Corp.'s Instant Set Polymer urethane, which Schweitz said has a longer, 60-second reaction time that allows it to fill the large, complex mold.
Schweitz said this was the ``most ambitious simultaneous engineering project'' Premold had ever tackled. ``There were more parts, more complexities, larger tools, and more at stake.'' But working with Brassil and his team at IDEO's Chicago office made things easier.
``They were quick to pull together concepts and turn that into something manufacturable,'' Schweitz said.
Premold ended up using a three-piece epoxy mold for the tower unit's largest panel. The cavity consisted of two pieces split along the vertical axis of the part, with the mold core being the third piece. The design saved Midwest Dental some $200,000 compared with aluminum tooling costs.
``The money saved was more than enough to pay for the molds for the other parts,'' Schweitz said. The toolmakers made their molds straight from IDEO's three-dimensional, computer-assisted-design files.
The design of the epoxy tool also allowed Premold to mold the flared fenders or wheel skirts as part of the enclosure panel, adding to the pleasing aesthetics. If the panel had been pressure formed, the flared fenders would have had to have been glued on, Brassil said. The RIM PU panels help absorb noise from the pumps and motors inside, he added.