Occasionally, breast implants may break or leak. The saline fill is salt water and will be absorbed by the body without ill effects. Older implants with silicone gel can leak also. If this occurs, one of two things may occur. If breakage of the implant shell that has a contracture scar around it, then it may not feel like anything has happed. If the shell breaks and there is not a contracture scar, then leakage into the surrounding tissue results in a sensation that the implant is deflating.

The leaking gel may collect in the breast and a new scar may form around it. In other cases gel can migrate through the lymphatic system to another area of the body. Breaks may require a second operation and replacement of the leaking implant. If the gel has migrated it may not be possible to remove all of the silicone gel. This silicone gel is the what some say is related to the initiation of connective tissue disorders.

For silicone gel and saline-filled implants, some causes of rupture or deflation include : damage by surgical instruments during surgery, overfilling or underfilling of the implant with saline solution (specific only to saline-filled breast implants), capsular contracture ,closed capsulotomy , stresses such as trauma or intense physical manipulation ,excessive compression during mammographic imaging, placement through umbilical incision ,site injury to the breast, normal aging of the implant ,unknown/unexplained reasons.

FDA completed a retrospective study on rupture of silicone gel-filled breast implants. This study was performed in Birmingham, Alabama and included women who had their first breast implant before 1988. Women with silicone gel-filled breast implants had a MRI examination of their breasts to determine the status of their current breast implants. The 344 women who received a MRI examination had a total of 687 implants. Of the 687 implants in the study, at least two of the three study radiologists agreed that 378 implants were ruptured (55%). This means that 69% of the 344 women had at least one ruptured breast implant. Of the 344 women, 73 (21%) had extracapsular silicone gel in one or both breasts. Factors that were associated with rupture included increasing age of the implant, the implant manufacturer, and submuscular rather than subglandular location of the implant.

The most common complication of breast implants is capsular contracture, a tightening of the scar tissue that the body produces around the implant as a natural part of healing. Additional surgery may be required either to remove the scar tissue or to remove??and perhaps replace??the implant. In a prospective clinical study of saline-filled breast implants conducted by Mentor, the cumulative, 3-year, by patient rates of a first occurrence of capsular contracture Grades III and IV were 9% for the 1264 augmentation patients and 30% for the 416 reconstruction patients.

In a prospective clinical study of saline-filled breast implants conducted by McGhan, the cumulative, 3-year, by patient rates of a first occurrence of capsular contracture Grades III and IV were 9% for the 901 augmentation patients and 25% for the 237 reconstruction patients.