New Technology May Have Dental Hygienists Saying “Wow” Instead of “Ahhh”

OGDEN, Utah – A Weber State University professor and her students are pioneering a new technology designed to teach dental hygienists how to administer anesthesia to patients, without exposing live subjects to the pain and anesthetic of an actual injection.

Assistant professor of dental hygiene Kami Hanson and her undergraduate student researchers have spent three years working on developing and refining a mixed-reality system that combines virtual and tactile components to provide a realistic learning experience.

Historically, dental hygienists learn to anesthetize patients by practicing on each other and then advance to actual patients. In recent years, the dental community has raised ethical concerns about using live patients for clinical practice, because anesthetic medication (with its inherent risks) is absorbed into the bloodstream for non-treatment purposes.

“Dental hygienists learn to administer local anesthesia through cognitive abilities, procedural knowledge and motor skills,” Hanson said. “Educators are seeking ways to provide students with a ‘hands-on’ experience without practicing on real patients.”

Hanson recalls starting from the ground up with design and development of the mixed-reality technology, which allows users an augmented perception of reality while interacting with virtual three-dimensional objects. Given the large amount of computer expertise needed, Hanson hired Howard Rose of Imprint Interactive to assist with software development and three-dimensional object modeling.

“This is a novel approach in dentistry, because we’re taking virtual application to the dentist’s chair,” Hanson said. “The technology allows students to learn techniques for local anesthesia in a virtual setting with a consideration of the real limitations of the dental chair and the patient’s head.”

With the current version of the Local Anesthetic Mixed-Reality System (MRS), students sit beside a dental chair with head-mounted virtual reality glasses covering their eyes.  On the display they see a three-dimensional object that represents a human head, teeth and oral cavity.  Students also place a data glove on their left hand and hold a syringe in their right so they can see both their hands in the virtual world and experience their movements in real time.

Students must recognize anatomical landmarks in the mouth to locate the correct placement for the syringe, which must then be injected at the proper angle to ensure the anesthesia will be effective. As the student advances with the handheld needle they will actually penetrate liquid latex at the site of penetration to simulate the penetration of real tissue. The three dimensional objects in the simulation replicate the resistance of tissue and bony sites in an actual patient, so students learn to recognize when the syringe makes contact with the correct placement along the jawbone.

Hanson and her students continue to conduct trial tests of the system to modify and refine it.
Hanson believes the system could serve as a bridge between students learning in the classroom and working on live patients. She would like to see the MRS system used for student competency exams eventually, in place of live volunteers.

Hanson and her senior students recently presented their research at a national conference in Dallas. They will demonstrate the technology to the Northern Utah Dental Hygiene Association on April 12 at 1:30 p.m. at Weber State University Davis Campus in Layton.

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John Kowalewski, director of Media Relations
(801) 626-7212 •
Kami Hanson, assistant professor of dental hygiene
801-626-6831 ·