The A. P Critchlow Company in Florence, Massachusetts, which made buttons, daguerreotype cases and picture frames, evolved into the Florence Manufacturing Company by 1866. Their premier product, the Pro-phy-lactic toothbrush, occasioned a change in name to the Prophylactic Brush Company. In 1931, it was bought out by the Lambert Company. The Lambert Company merged with Warner-Hudnite Company in 1932 to become Warner-Lambert Prophylactic Division of Standard Oil of Ohio. The abbreviation of "Pro-Brush" was adopted.