Henri-Edmond Casgrain (born August 5, 1846, L'Islet, Canada East; d. 30 October 1914, Quebec City, Quebec)^[1] was a Canadian dental surgeon, inventor, city councillor and the first motorist in Quebec.^[2]

Casgrain studied at Collège de Sainte-Anne-de-la-Pocatière from 1857 to 1864 and went on to medical studies at Laval University in Quebec City from 1866 to 1868.^[3] Following Laval, he studied dentistry at Pennsylvania College of Dental Surgery in Philadelphia.^[4]

In 1879, he married Emma Gaudreau Casgrain.^[5] He was 15 years older than Gadreau.

He trained his wife in dentistry.^[6] In 1898, she became the first woman in Canada to be admitted to the profession of dentistry, when she graduated from the College of Dentists of Quebec and obtained her license.^[7] She practiced until 1920.^[8] Casgrain and his wife had an office on Rue Saint-Jean from 1898.^[9]

Active in the College of Dental Surgeons of the Province of Quebec, Casgrain became vice-president 1904.^[10] He also sat on Quebec city council from 1900 to 1904, as alderman of the Palace district.^[11] He was buried in the Notre-Dame de Belmont cemetery, where Emma Gadreau Casgrain had an impressive mausoleum built in 1915.^[12] Newspapers wrote up his funeral, at the Basilica of Quebec, adding that he had been the first Quebec motorist.^[13]

Scientific American magazine presented his dentistry invention on March 30, 1895: a small device that allowed the fusion of aluminum with other metals. Casgrain patented the device, which he started using in 1892.^[14] He also sold a method of making dentures to the Buffalo Dental Manufacturing Company.^[15] In 1896, he patented an acetylene gas lamp.^[16] He also patented a machine for making cigarettes.^[17]