Tools of dental professor’s bitemark research included in Smithsonian exhibition

BUFFALO, N.Y. — Mary Bush, a forensic dentist and associate professor of restorative dentistry in the University at Buffalo School of Dental Medicine, has devoted more than a decade of her career to refuting that bitemark evidence can determine a suspect’s guilt.

Now, tools used in her groundbreaking research will be included in a yearlong exhibition at the Smithsonian’s National Museum of American History in Washington, D.C. The “Forensic Science on Trial” exhibition, which opens June 28 and runs through June 2025, explores the way people influence the development, presentation and interpretation of forensic science.

Objects and archival documents on view span 150 years of historic cases and include about a dozen different forensic techniques, from hair to handwriting analysis.

“This is the ultimate honor,” Bush said. “We had such a battle with the legal system and the pro-bitemark people trying to discredit us. Having evidence of our work included in the Smithsonian feels validating.”

“Forensic Science on Trial” looks at how the science used in criminal trials has evolved. Divided into three sections, “Of People,” “By People” and “For People,” the exhibition underscores the long-standing desire to create systems that can reliably turn trace evidence of criminals into convictions, how the collection and judgment of data can be influenced by personal beliefs, and the way the past can shape how data is exhibited for those tasked with deciding guilt or innocence.

The UB pieces include dental models created by graduate student Hannah Holtkoetter and an apparatus used for testing bitemarks on cadavers, which Kyle Thorsrud, ’09, now a practicing oral surgeon in Dearborn, Mich., created while working in Bush’s lab. It is juxtaposed with a photograph of a wax bite impression of Ted Bundy’s teeth used in his 1979 murder trial.

“When I told Kyle about the exhibition, he was very excited,” Bush said. “He has young children and will be taking the family to the museum this summer to see it.”

Bush said she plans to travel to Washington herself to see the exhibition in early September.

Other artifacts in the exhibition include arsenic tests from the 1872 trial of Lydia Sherman, who was suspected of poisoning three of her husbands and eight children; one of the earliest polygraphs used for lie detection; an early sexual-assault examination kit; and materials related to fingerprinting and DNA identification on loan from the FBI.

The exhibition also looks at how the media, through news coverage and on fictional television shows, such as “Dexter” and “CSI: Crime Scene Investigation,” shape how the public understands forensic evidence and what is called the “CSI effect.”

Loans from individuals as well as the Massachusetts and New Jersey State Police departments allow for the presentation of materials from multiple “trials of the century.” These include a handwriting analysis display from the 1935 trial of Bruno Richard Hauptmann, charged with the kidnapping and murder of the son of aviators Anne and Charles Lindbergh, and a copy of DNA autoradiographs from the 1994–95 trial of O.J. Simpson.

Bush’s bitemark research

For years, Bush argued that human dentition is not unique with regard to bitemark analysis and seemingly perfectly matching bitemarks could belong to a litany of suspects.

Bitemarks aren’t only inadequate, Bush said, but they also have been misused in courtrooms. In a commentary published in the May 2023 issue of the Journal of the California Dental Association, Bush pointed out that 26 people have been wrongly convicted primarily because of a bitemark found on the victim. At least three of the suspects ended up on death row.

“People assume that human dentition is unique because dental records are often used to identify the dead,” she said.

However, in those cases, the combination of 32 teeth — present, missing and restored — are analyzed, compared with only the incisal edge of the six teeth that typically leave a bitemark, she noted.

Throughout her research, Bush discovered that the teeth marks that fit best usually do not belong to the actual perpetrator.

In addition to publication of her research, Bush and her team have testified before the Texas Commission on Forensic Science in 2015 and the President’s Council for Assistance in Science and Technology in 2016.

“I am thrilled that the work of my team is on display in this national exhibition,” Bush said. “We did our research diligently but quietly, never imagining it would resonate the way it has.”