John Nathan Crouse

John Nathan Crouse (1842–1914) was a dentist in Chicago in the 19th and early 20th centuries, best known for his work organizing dentists to litigate against the use of patents on dental procedures. He was a charter member of the Illinois State Dental Society, and founded the Dental Protective Association, an organization that litigated against process patents in dentistry, serving as its president until 1913. He also served a term as president of the American Dental Association, then known as the National Dental Association.

Early life and education Crouse was born in Chester County, Pennsylvania, on September 15, 1842, the son of Daniel and Mary Crouse.

Crouse practiced dentistry in Mount Carroll starting in 1864, then traveled to the Pennsylvania College of Dental Surgery, where he obtained his DDS in 1867.

Dental Protective Association In 1888, Crouse founded the Dental Protective Association (DPA) to protect against legal threats to the profession. From 1895 to 1908, the Association published the Dental Digest as its official organ. The DPA defeated every patent suit it fought through at least 1900.

Deeper problems arose in 1910 over Dr. William Taggart's invention of a method of preparing gold inlay fillings. Taggart's process patent was invalidated by the DC Court of Appeals in Boynton v. Taggart in 1912, dealing a further blow to the DPA's prestige.

Death and legacy Crouse died of heart failure on January 16, 1914. He was buried at Rosehill Cemetery in Chicago. The DPA remained in operation through at least 1922.