This is by far the most common question I hear during consultations for breast augmentation. There are a number of things to consider when choosing the proper breast implant, and these can be discussed specifically with you doctor during your consultation.
In the United States there are currently two general types of breast implants available, saline (salt water) and silicone. This refers to the material that the implants are filled with. There are important differences between the two, and each have their benefits. It is important to know that after many years of scientific studies, it has been shown that both implants are safe and silicone implants have proven to have no relationship to autoimmune disease or other systemic illness. This does not mean, however, that there are no risks associated with breast implants and breast implant surgery.
In general, silicone implants are considered to be a more "natural" implant. This means that the implant has a softer feel, and usually takes on a more natural shape as well. Further, silicone implants are more difficult to feel inside the breast, allowing the augmented breast to feel like your own body tissue. Silicone implants are approved for use in appropriate patients 22 years old and older.
Saline implants also have some advantages. First, because the implants are filled during the surgery, the incision needed to place the implants is slightly smaller than that used for silicone. Also, for the same reason, your surgeon has the ability to adjust the size of the implant (within a recommended range) during the surgery, and this may be important for woman with significant size differences between their breasts. Another advantage of inserting the implants before they are filled is that it allows your surgeon more options of where to place the scar. One drawback of the saline implant is especially important in thinner women, or women with very little breast tissue. Occasionally the implant can be felt through the breast tissue, and sometime ripples or wrinkles in the implant can be felt as well. In some cases these ripples can be seen, especially when a patient leans forward or bends over.
After your exam you will be able to decide with your doctor which implant is the best choice for you.
Many patients also ask about other implant options such as "tear drop" implants, or textured implants. In general I prefer to use smooth round implants for cosmetic breast augmentations - as I have found that these provide the longest lasting, most natural results. I reserve the use of anatomic (tear drop) implants for patients with special needs and for breast reconstruction. When using anatomic implants it is important to use a textured implant to prevent rotation of the implant, because round implants are symmetric, there is no need for texturing. Again, the only way to determine what is best for you is to have a consultation with a Board Certified Plastic Surgeon.