Knowing the work would have immediate impact motivated the team, which took the project on at the request of UTDB-H faculty who took Rice's dental backpack to Nicaragua last summer. "They realized that during procedures, the clinicians were using gauze to soak up saline and the blood, and they would end up with huge amounts of hazardous waste," Wirth said.
The goal was clear: The unit had to be portable, low-cost and run on alternative energy sources where AC power was limited or unavailable. It also had to handle multiple patients on one charge, use various tip sizes and prevent fluids from flowing back into the patient's mouth.
The team evaluated a number of portable vacuums and finally settled on an 18-volt DeWalt wet/dry unit. They split the battery from the main unit and put a foot switch between the two so dentists could turn it on and off as needed without disrupting their work. All the materials for the device cost less than $200.
Extensive testing proved the vacuum would hold up over five hours of heavy-duty use. "We would turn it on, suction 500 milliliters of water, turn it off and leave it for three minutes and then do it again," Wirth said. "With intermittent use, we really don't see power as a problem at all."
The students built in several ways to control backflow, adding a hand-operated valve at the tip, building in L-shaped joints at the top and bottom of the hose and using tubing that won't kink. And, Ma said, "If you leave the vacuum running for a couple of seconds b
|Contact: David Ruth|