In the past, one of the disadvantages of a silicone gel breast implant for a breast augmentation was the need to make a longer incision to place it compared with a saline implant. This is because a gel implant is placed completely filled, as opposed to a saline implant which is placed empty, and then filled after placement. By using a Keller Funnel, most silicone gel implants can be placed through an incision that is the same length as the one used for a saline implant. This results in a shorter, less visible scar. Because the implant never touches the skin when the Keller Funnel is used, there is also less chance of bacterial contamination of the implant, which likely equals a reduced chance of breast implant infection. Although the cause of capsular contracture is not known, a widely accepted theory is bacteria; the use of a Keller funnel may greatly lower the possibility of a capsular contracture as well.