During the consultation today, a patient asked me, “Aren’t saline implants harder?”

Well, it actually depends.

Let me start by saying that if you have ever held a saline implant and a silicone gel implant side-by-side, you know that they feel completely different, and that in certain respects there is little similarity between them. But this woman’s question addressed the firmness of the implant; and she was really asking if a saline-filled breast implant felt firmer than a silicone gel-filled breast implant.

For the purposes of this discussion I will be referring round saline-filled breast implants and round silicone gel-filled (fourth generation, moderately cohesive, responsive gel) breast implants.

Silicone gel  implants are filled by the manufacturer. The silicone gel fill-to-shell volume ratio is consistent for a given implant style. This means that each implant has essentially the same consistency and feel. A 275 mL silicone gel implant therefore has the same consistency as a 300 mL silicone gel implant, which feels like a 325 mL silicone gel implant, which in turn feels the same as a 350 mL silicone gel implant, and so on, and so on… So even though the volume of each implant differs, the consistency remains constant. So the silicone gel implant that you touch and feel during your consultation will be no different than the consistency and feel of the implant that is actually placed in your breast.

In contrast, saline implants are shipped empty, and are filled by the operating surgeon. Each saline implant has a minimal fill volume, and a recommended maximum fill volume. If the surgeon chooses, a saline implant may be filled above the maximum recommended volume (over-filled). Since the fill volume  of a saline breast implant can therefore vary depending upon the circumstances of the surgery, the consistency and feel of the saline implant will subsequently vary as well. When a saline implant is filled to its minimum volume, it has a softer feel (The shell has some flexibility and a fluid wave can be produced by tapping the implant since the fluid has some room to move around within the shell.) As a saline implant is filled more, the consistency becomes progressively firmer. At the maximum recommended fill volume a saline implant has less softness (and the shell has less flexibility.) As the fill volume continues to increase above the recommended maximum, the implant now develops a firm consistency (the implant shape becomes slightly distorted and the shell is stretched by the pressure of the increased volume).

In comparative terms, if a 275 mL saline implant is filled to 275 mL, and a 300 mL saline implant is filled to 300 mL they will have the same consistency and feel. But a 275 mL implant filled to 300 mL will feel firmer than it does at its minimal fill volume (275 mL). And if that same 275 mL saline implant is now filled to 325 mL, the firmness of the implant increases even more. As filling is continued and the implant volume reaches 350 mL, the implant becomes even harder. So it is possible that the saline breast implant you touch during your consultation may have a different consistency and feel than the implant that is actually placed in your breast.

Although saline and silicone gel do not feel anything alike, at lower fill volumes, the consistency and feel of a saline breast implant will more closely approximate the softness that of a silicone gel breast implant. However, as the saline implant is filled more and more, the implant can become quite firm and then feels nothing like a silicone gel implant.

During your consultation it is important to see and feel several different types and styles of breast implants. This will provide you with a better understanding of the characteristics of these implants so you can make a decision that is right for you.