I’m booked in to have 550cc HP over the muscle but am concerned about sagging in the future. Would under/dual plane be better?

Dear Sarahtonin_x,
I almost always place implants submuscular. It lowers the rate of capsular contracture significantly. In addition, it looks much more natural because the muscle provides covering over the implant so its not as round on the top. I've also noticed the implants drop less over time when they are protected under the muscle.
Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

I think that most plastic surgeons would agree that a breast augmentation result where the implant is placed under the muscle (dual plane) tends to have better longevity than a breast implant placed over the muscle.  For these patients in whom the living is made by athletic performance, the implant can be placed above the muscle.  Other patients will be happier long term with submuscular placement.
Kenneth Hughes, MD, ABPS Board Certified Plastic Surgeon
Los Angeles, CA

When undergoing breast augmentation there are a number of choices which need to be made: saline or silicone? Volume: Larger or smaller? Incision? However, one of the most commonly debated choices is that of implants placement: subglandular/ submammary vs. subpectoral/ submuscular? While many surgeons recommend submuscular placement there are distinct differences to each approach.
 Subglandular Augmentation (“overs”): 
Subglandular augmentation means place of the implant underneath the breast tissue but above the pectoralis muscle. Subglandular placement spares the pectoralis muscle which leads to reduced post operative pain/discomfort and no impact on muscle function post augmentation. Recovery is also faster.Subglandular augmentation can impact mammographic evaluation of the breast. However, as dedicated breast radiography has become more prevalent this has become less of an issue. Fellowship trained radiologists have become familiar with evaluating breasts post augmentation. It is also important to note that implant position does not interfere with visualization of breast tissue via contrast enhanced MRI (the most sensitive and specific study available for breast cancer detection).Studies suggest there is an increased risk of capsular contracture when implants are placed in a subglandular space.Aesthetically, implants placed superficial to the pectoralis major create a rounded, convex appearing breast profile. This effect is camouflaged, at least initially in larger breasted patients. However, as a woman ages fat atrophies and breast tissue descends. The result is a more noticeable implant specifically in the upper pole. Similarly, patients who have thin coverage superiorly are more likely to be able to perceive the implants and at higher risk of visible rippling when compared to subpectoral augmentation.Subglandular implants can also create the illusion of improved cleavage by preferential over-dissection of the central/medial pocket allowing the implants to be forced more to the midline. There is no limiting muscle as there is in a submuscular augmentation. 
Subpectoral Augmentation/Sub-muscular/Dual Plane (“unders”): 
Subpectoral augmentation is technically a bit of a misnomer. Traditionally, subpectoral augmentation involves the release of the pecotralis major muscle from its lower attachments. This allows the muscle to “window-shade.” The upper hemisphere of the implant sits underneath the muscle (dual plane). This release contributes much of the discomfort encountered postoperatively by patients.Subpectoral implants have a lower rate of capsular contracture.Aesthetically, in contrast to submammary implants (which are prominent in the upper pole- especially in thinner patients), the pectoralis muscle both conceals the underlying implant and flattens the upper pole. This flattening effect creates a natural sloping as one proceeds from the upper portion of the implant to the lower portion.The most commonly cited drawback to sub-muscular augmentation is the animation deformity associated with contraction of the overlying muscle.In my practice, the vast majority of patients will have the implants placed submuscular for all the reasons listed above.With regards to your specific question, there are a number of issues to consider. Submuscular augmentation does result in a real but negligible (for most) loss of strength. Animation can be a concern as well. Submuscular shape is different but for most preferable to subglandular (see above). However, the overall risks are lower when implants are placed deep to the muscle. It is for this reason most patients prefer submuscular augmentation.
As always, discuss your concerns with a board certified plastic surgeon (ABPS).
Donovan Rosas MD
Board Certified by the American Board of Plastic Surgery
Member: American Society for Aesthetic Plastic Surgery, American Society of Plastic Surgeons
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