1822
On March 9, 1822, the first United States patent for artificial teeth is issued to Charles Graham, marking an early milestone in dental prosthesis technology and the formal recognition of modern dentures.
1845
Wilhelm Pfeffer is born on March 9, 1845. The German botanist later pioneered experimental plant physiology and methods for measuring osmotic pressure in plant cells, laying foundations for modern botany.
1856
Edward Goodrich Acheson is born on March 9, 1856. The American inventor discovered silicon carbide and developed industrial electric furnaces for producing abrasives, transforming manufacturing and toolmaking.