Charles Stent Charles Stent Charles Stent (1807–1885) was a 19th-century English dentist notable for his advances in the field of denture making. In 1847, Edwin Truman introduced gutta-percha as a material for making dental impressions; however, this was unsatisfactory for several reasons, including its tendency to distort upon removal from the patient's mouth, and to shrink upon cooling. In 1856, Stent added several other materials to the gutta-percha, notably stearine, which markedly improved the plasticity of the material as well as its stability. He also added talc as an inert filler to give more body to the material, and red colouring. The
Charles Wheatstone Charles Wheatstone Sir Charles Wheatstone FRS (6 February 1802 – 19 October 1875), was an English scientist and inventor of many scientific breakthroughs of the Victorian era, including the English concertina, the stereoscope (a device for displaying three-dimensional images), and the Playfair cipher (an encryption technique). However, Wheatstone is best known for his contributions in the development of the Wheatstone bridge, originally invented by Samuel Hunter Christie, which is used to measure an unknown electrical resistance, and as a major figure in the development of telegraphy. Charles Wheatstone was born in Barnwood, Gloucestershire. His father was a music-seller in the