Fill: Underfill vs. Overfill

Hint: Always Overfill Saline Implants

On this page, Dr. Loftus will walk you through the issue of saline implant fill and why this is important.

Saline breast implants are filled with air when they arrive from the manufacturer. During surgery, your surgeon will evacuate the air and fill each implant to the desired volume of saline. The amount within each implant can be adjusted by 25-30 ml before concluding the procedure. Overfilling to the recommended volume reduces deflation, rippling, and sloshing. Hence, implant manufacturers encourage overfilling. Filling beyond the recommended overfill volume is not usually advocated by the manufacturers, as doing so might increase deflation. Example: if an implant is described as a 300 ml implant, then it should be optimally overfilled to 325 ml (Mentor) or 330 ml (Allergan). If an implant is described as a 300-325 ml implant, it should be optimally overfilled to 325 ml.

Deflation

Implants that are not filled to the recommended minimum capacity have a higher risk of deflation than those filled to their recommended maximum capacity (overfill volume). Their edges fold repeatedly and weaken, just as a piece of paper that is folded along the same line repeatedly will tear easily. That is why implant manufacturers recommend that implants be filled to the recommended maximum fill volume, also called the "overfill" volume.

Rippling and Sloshing

If you have a waterbed, you may have noticed that the amount of water in the mattress alters its degree of rippling and sloshing. The same is true for saline breast implants. Both effects can be reduced by overfilling the implants.

Summary

There are multiple advantages to overfilling, and no disadvantages.