In 1962 Cronin and Gerow introduced the first generation silicone breast implant which was manufactured by Dow Corning Corporation. A two-piece envelope with a seam along the periphery constructed of a thick, smooth silicone elastomer made up the shell of these early breast implants. The anatomically shaped or teardrop shaped implants were filled with a moderately viscous silicone gel. To help maintain the implant in proper position, several Dacron fixation patches were affixed on the posterior aspect. Due to the high contracture rate of these early breast implants, manufactures were forced to develop second generation silicone breast implants.