I feel the urge to use the phrase "going green" to describe what a few dental students have accomplished, but since we’re talking about teeth and oral hygiene, I’ll resist the urge.

Let’s just say this group of dental students has engineered a solution to the wastefulness of one-time use plastic saliva ejectors that most U.S. dentists use daily. Dentists must dispose of plastic saliva ejectors after each patient in accordance with infection control protocols.

But thanks to the ingenuity of these conservation-minded dental students, this could become a thing of the past.

The four students at the University of Costa Rica (UCR) have developed a metallic saliva ejector that can be cleaned in the autoclave and reused again and again.

For example, the team estimated that the UCR Faculty of Dentistry throws away 166 ejectors each day, 3,317 each week, and almost 4,000 each year.

The students also note that if the average dental office sees 12 patients a day, they will throw away a little more than 3,000 ejectors every year. Metal ejectors would eliminate this waste. Not to mention the cost savings!

"Plastic saliva ejectors are one of the instruments used by dentists that generate a big impact at the environmental level," said Yulieth Segura Castillo, one of the students. "So we proposed a stainless steel, autoclavable, surgical-grade ejector to reduce this impact through a design that meets all of the conditions for professionals who decide to change from the usual plastic ejector."

The dental students began their research and development process with several prototypes made out of various metals.

During the testing phase, some could not stand the heat, were deformed or failed during use. Next, they worked with a metallurgist to develop a final prototype that successfully passed all sterilization and functionality tests.

Although a metal saliva ejector will cost more than a plastic one, the students call the metal ejector a long-term investment. It will save dentists both the costs of buying thousands of plastic ejectors as well as the costs of disposing of them, since many waste companies that collect biological waste charge by weight.