Researchers at the University of Hong Kong's dental school have invented a new material to replace extracted human teeth for dental research after it encountered difficulty in acquiring real teeth during the pandemic.

Working with researchers from Wuhan University and the United States's Drexel University, the HKU Faculty of Dentistry research team found new elliptical frustums of fiber-reinforced composite materials and compared their properties to that of human dentine.

Extracted human teeth have long been used in dental research but obtaining them became difficult during the pandemic. And real teeth also have working limitations because of their unstandardized sizes and short storage time of normally under a month.

The team tested the new dentine analog materials for their mechanical strength, elastic modulus, indentation hardness and fatigue behavior.

They then fabricated the new materials with specific sizes and shapes mimicking natural human teeth and adhered them to ceramic crown crowns before subjecting them to fatigue loading tests.

The new materials were found have a comparable fatigue failure load and lifetime to extracted human teeth. The team also conducted a finite element analysis, which stimulated physical phenomena using a numeral technique.

They found similar stress levels and distributions between the new materials and extracted human teeth.

The study has been published online in the scientific journal Dental Materials and a dental company has contracted the faculty to test commercial ceramic products using the new dentine materials.

The team's principal researcher, James Tsoi Kit-hon, who is also the faculty's associate professor in dental materials science, hoped the study can help ease the problem of inadequate acquisition of human teeth.

"We hope this study can help researchers facilitate predictable laboratory research with the aid of dentine analog materials," he said. The research was supported by the General Research Fund under the government's University Grants Committee.

Preliminary results of the study were first presented by a co-investigator, Chen Yanning, at the Academy of Dental Materials annual meeting in Athens, Greece from September to October last year. Chen was awarded the Student Travel Award.

eunice.lam@singtaonewscorp.com

HKU team invents material to replace extracted teeth