Thank you for your question!
First, I would like to bring to your attention the fact that breasts must follow a set ideals to be classified as natural.
Natural breasts have the following characteristics:
- The areola – dark pigmented region around the nipples – should not be large relative to your nipple
- The nipple should be above the breast fold – inframammary fold
- The 2 nipples should form an equilateral triangle with the notch of your breast bone
- The breasts should not be sagging
- The nipples should sit directly behind the part of the breast that projects the fullest
- The breasts should appear symmetrical
A recent study by Dr. Mallucci and Dr. Branford, titled “Shapes, Proportions, and Variations in breast Aesthetic Ideals,” gives us 4 set of ideals in beautiful and natural-looking breasts. They are as follows:
- An upward pointing nipple (angled at 20 degrees)
- A slope in the upper pole of the breast
- A tight curvature (convexity) in the lower pole of the breast (i.e., below the nipple)
- An upper pole to lower pole ratio of 45:55 (i.e., the percent of fill below the nipple should be 55% compared to 45% above the nipple)
If your breasts meet these ideals and those I mentioned above, they will look natural.
That being said, there are many factors that go into creating natural-looking breasts, and a combination of the right choices contributes to achieving the desired result. I mention some of these factors below.
1) The size of the implant – a large implant that exceeds your breast boundaries, or overly stretches your breasts, or is too round will make your breasts look unnatural. In fact, there is higher likelihood of bottoming out (i.e., an empty upper pole, nipple sitting too high on the breast), double bubble deformity, implant malposition, implant visibility, breast sagging, and breast tissue wasting. So going big is good, but going beyond limits will get you in big trouble…pun intended.
A board-certified surgeon will always determine a suitable range for the implant volume after conducting some breast measurements. Measurements such as breast base width, the amount of breast skin stretch, nipple to breast fold distance under maximal stretch, skin quality, chest wall asymmetries, etc. will be looked into. For example, if your breast base is very wide, we will require a higher implant volume to avoid the “rock in a sock” appearance.
2) The profile of the implant – How much the implant protrudes or sticks out in the forward direction influences how much stretch is put on the overlying breast skin, and excessively stretching the skin results in negative consequences.
3) The shape of the implant – majority of surgeons prefer round and smooth implants, but if your breasts do not have a natural shape to begin with as we see in patients who have tuberous breasts, then you may require the use of anatomic implants whose lower half is more loaded in volume than the upper half corresponding with the desired natural look.
4) Incision placement – incision location not only determines the degree of trauma to breast’s soft tissues, exposure of the implant to breast’s endogenous bacteria, pocket visibility and control, but also the implant’s position vertically and horizontally relative to the chest wall. For example, compared to the tranaxillary (armpit) or the areola (around the nipple) incision, the inframammary (IMF) incision better allows your surgeon to lower the inframammary fold to increase its distance from the nipple. In many patients, the inframammary fold needs to be lowered in order to allow the implant to rest at a level that appears natural relative to the position of the nipple and areola, and in order to prevent the appearance of excessive upper pole fullness. I need you to realize that an overly full upper pole will make it obvious that you got implants to enhance your breasts.
5) Pocket – Now to answer your original question, the decision to go behind the muscle or above the muscle has to do with the amount of soft tissue coverage – “padding” under the skin. Choosing a pocket that is tight with sufficient soft tissue coverage not only prevents implant visibility, palpability, and risks of excessive stretching on the breast, but also excessive implant movement into the outer or inner sides of the breasts. A hand-in-glove fit for the implant allows for a natural and long-lasting result. Your surgeon will do a pinch test in the upper pole of the breast to see how much “padding” you have. If you have less than 2 cm, then you do not have much padding and it would be best to go under the muscle. Generally speaking, if your ribs are visible under the muscle, then you do not have much “padding.” If however, you have more than 2 cm, then you have the option to go over the muscle or under the muscle. Under the muscle placement of the implant will provide a more natural look because the muscle helps to maintain a slope for the upper pole while allowing for a curvature in the lower pole. If you are hoping to fully preserve the functionality of the pectoralis major muscle due to athletics or body building, or if you have a shapeless, constricted, tuberous, sagging breasts, and do not have a proper cleavage, then over the muscle may be a better option. Over the muscle (subglandular) implant placement may cause tissue wasting, interference with mammography, hold higher risk for capsular contracture and synmastia (disappearance of the cleavage gap).
Now to answer your original question about what allows a more natural look and feel, saline or silicone? It depends, but before a definite conclusion can be achieved, the filler option has to be analyzed in relation to your breast characteristics, your values and preferences, and desired looks.
1) Saline Implants
Since they come in a non-inflated form, the implant can be inserted without having a large incision on the skin and this results in minimal scarring adding to a natural look.
The non-inflated form also allows the implant to be placed through all incisions including the transaxillary incision which is referred to as the “scarless technique” because there is no scar on the aesthetic unit of the breast itself.
Saline implants have a 1%/year chance of spontaneously deflating (10% chance after 10 years), and although no one can predict when this will happen, it can be embarrassing if this happens while at a party or at work to due sudden changes in breast size.
Saline may not make the breasts feel natural because it is not compressible – there will be a strong resistance when you squeeze your breasts making them feel firm rather than soft and squishy.However, the difference in feel compared to silicone disappears with the amount of breast tissue you have. Special care should be taken on choosing the right size and shape so that they are proportionate with your overall body contour.
Saline implants have higher chance of rippling (wrinkling) which may be visible if you have less soft-tissue coverage (i.e., soft tissue refers to your skin, fat layer beneath your skin, and the breast tissue). The thinner you are the more you see it. Rippling often develops on the outer perimeter of the augmented breasts: on the side, bottom or in between the breasts. It can be caused by under-filling of the implant. Solutions would be to choose a moderate sized implant, choose behind the muscle implant placement, choose smooth surfaced implant, and gain weight. That being said, visible rippling can occur with saline implants even behind the muscle on the lateral (outer) aspects of the breast near the breast fold when you lift your arms, or lean forward.
Silicone as a filler will make the implant feel softer resembling the feel of the natural breast tissue due to its gel-like cohesiveness. This characteristic also makes the implants less detectable even by touch or feel.
Silicone implants are ideal for thin woman with small breasts
Silicone implants experience minimal rippling which is barely visible and may occur mostly when patients lie down on their breasts
Silicone’s cohesive gel allows more a greater variety of implants – i.e, shaped implants are only silicone-based and provide a natural look which is helpful in treating certain conditions related to the chest wall or breast development.
Silicone implants have a 1%/year chance of rupturing similar to saline implants (10% chance after 10 years), however, the rupture is silent which means that the breast size will remain stable. The downside is that you will require an MRI test to diagnose the gel leakage/rupture.
Silicone implants cannot be safely introduced behind the breast through the transaxillary incision unless they are small or moderately sized.
Silicone implants appear in pre-filled form which means implant insertion requires a longer incision on the skin to prevent damage it, and its volume cannot be manipulated.
The New Silicone Implants:
There is often a concern over safety and monitoring of silicone implants, but these implants have a similar complication rate compared to saline implants, and several clinical trials have shown the safety and longevity of silicone implants that allowed them to be approved by the FDA since 2006. Please note that today's 5th generation silicone cohesive gel implants have been proven to be very durable and safe. In fact, they have lower rates of capsular contracture and gel diffusion. These 2 things were the major concern from previous silicone implants. The new silicone implants also have thicker shells, wider variety of surface textures, and implant shapes.
Verdict: You may want to consider Silicone implants if your primary concern is a natural looking result.
Hope this helps!