How does an antique black carriage used by the wife of Napoleon III to flee Paris in 1870 figure prominently in the 100th anniversary of a dental school's flagship building?

You might be surprised.

Philadelphia native Thomas W. Evans was perhaps the most famous dentist of the 19th century. He endeared himself to Emperor Napoleon III and his wife, Empress Eugénie, as both doctor and confidant. And when Napoleon was captured in 1870 during the Battle of Sedan, Evans lent his carriage to help the fallen leader's wife escape angry mobs who were trying to overthrow the government.

When Evans died in 1897, he left his entire estate - including that little carriage with a grand history - to his hometown's University of Pennsylvania, with the condition that it create a "world-class" dental school. Penn already had a dental school but soon opened a new dental institute with a museum in the name of its benefactor.

For decades, the dental school displayed the luxurious, four-seat landau carriage, but it closed the museum in 1967 to make way for a clinical dental wing.

Now, under the direction of dental school dean Denis F. Kinane and Lynn Marsden-Atlass, university curator and director of Penn's Arthur Ross Gallery, the carriage - which had been on loan to a museum in France since 1993 - has gained newfound importance.

It and other Evans artifacts are being restored, displayed, and heralded for their parts in Penn Dental Medicine's history, in time for the 100th anniversary of the Evans building, still the school's flagship.

The carriage is displayed in the atrium at the main entrance to the dental school on 40th Street near Locust. Paintings and sculptures of Napoleon and George Washington, and a gold and tortoiseshell "Boulle writing desk," all of which belonged to Evans, grace Kinane's office. The items - except for the carriage, which will undergo further restoration by an Amish business in Lancaster County this summer - will be among the 150 items from Evans' cache on display at the Arthur Ross Gallery for three months beginning July 18.

"I'm interested in the history of the school, which is somewhat second to none," said Kinane, a Scot who in 2009 became dean of the 630-student institution.

Kinane underscored the importance of Evans - as both a dentist and a diplomat - to that history.

Evans was the first to use vulcanized rubber as a base for dentures, introduced nitrous oxide as an anesthetic in Europe, and was known for his work with gold foil fillings.

"He lifted the profession of dentistry from being a street-corner pursuit to being one of the subdisciplines of medicine," Kinane said.

The bearded West Philadelphia native lived an extraordinary life.

"Having moved from Pennsylvania to Paris in 1847 without even speaking French, he became the dentist of choice and trusted friend of a glittering array of kings, princes, empresses, grand duchesses, czars, sultans, and other potentates," Samuel Hughes wrote in an article for Penn's alumni magazine.

Evans was sent by Napoleon to speak to President Abraham Lincoln about the Civil War and persuaded Napoleon to leave France on the sidelines of that conflict.

He introduced the concept of an ambulance in the Franco-Prussian War after seeing them in action during the Civil War.

And he proved his friendship when Eugénie asked for help. He gave her his wife's hat to wear and with two other passengers in tow carefully navigated his carriage through Paris, away from the palace, so the story goes.

"When they passed through the Porte Maillot, Evans casually blocked the view of the empress with his body and a newspaper, and told the sentry that he and his friends were going for a drive in the country," according to Hughes' account.

Shortly after arriving at Penn, Kinane learned of the carriage's existence and wanted it back from France. Penn's board of trustees had lent it to the French national museum organization.

Marsden-Atlass visited the museum in the summer of 2013 and learned the carriage had been relocated to the Château de Compiègne, in Picardy in northern France. She photographed it and met with the curator, who offered to buy the carriage from Penn. She took that offer back to Kinane, who rejected it.

Six months later, Kinane visited the château and began negotiations to get the carriage back. It took nearly a year, but the vehicle was shipped to Penn last fall. Its exterior has since been restored, and its interior will undergo work this summer.

Kinane and Marsden-Atlass have also been working on getting the rest of Evans' items out of storage, documented, digitized, and restored.

"Many of these things were gifts to Evans from nobility all over Europe, not just the French," said Marsden-Atlass, who cited as an example a tankard given to Evans by the prince and princess of Wales. "What we've done is really bring this collection back to life."