• Subglandular (also known as overs)
• Subpectoral (also known as unders, partial unders, or partial submuscular)
• Full Submuscular (also known as full unders)

Subglandular
With subglandular placement, a pocket is made within the breast envelope, underneath the glands and fatty tissue.  The implant is placed within this pocket and has the most natural movement.  However, you must have adequate tissue in order to hide the breast implant.  The pluses of subglandular placement is that when you use your pectoral muscles, either when moving naturally or when working out, your breast implants do not "jump" or move unnaturally.  The downside is that you may be able to see the edges of some breast implants, and also some patients feel that their breasts begin to sag prematurely with the added weight.  Another downside is that when getting a mammogram, the subglandular placement of the implant makes it difficult to be able to fully see the breast tissue and might interfere with any abnormal diagnoses.  If you have breast cancer in your family history, you may wish to consider this and opt for a subpectoral or full submuscular placement which would allow a more complete view of the breast tissue.  The risk of Capsular Contracture is thought to be higher in subglandular placement as opposed to subpectoral or full submuscular.

Subpectoral
With subpectoral placement, the pectoralis major which is the largest muscle of the chest wall, is dissected away from the smaller chest wall muscle (called the pectoralis minor).  A pocket is made behind the larger muscle and the implant is placed in this area.  Depending upon the size of the breast implant, the pectoralis major muscle will cover about 2/3 of the breast implant.  This coverage better hides and contour irregularities which may be apparent from the insertion of a breast implant.  Patients with little to no breast tissue are often advised to have this breast implant placement.  Since the breast implant is partially covered by the pectoralis major, mammograms have less interference from the implant therefore a clearer reading is possible.  Chances of developing Capsular Contracture are also thought to be less with this placement.  The downside to this placement is less natural movement of the breast when you flex your pectoralis muscle during normal movement or when working out.  The implants are distorted due to pressure of the flexing pectoralis and may give it the appearance of "jumping".

Full Submuscular
The full submuscular placement is when the breast implant is placed under the pectoralis major, as above, but also covered with the serratus muscle fascia and the fascia of the upper rectus abominus.  This placement supplies the best coverage, although movement is not as free as with overs, or even subpectoral placement. The full submuscular placement creates a sort of internal bra so future ptosis (sag) is less likely, or at the very least, delayed.   However, if you have considerable sag and get this implant placement without a lift, you will develop what is referred to as Double Bubble.  Double Bubble is when you seem to have an upper bulge (the breast implant) and a lower bulge (your own breast tissue and skin).  A condition called Bottoming Out (when the natural breast crease, or the crease created by your surgeon, lowers on its own and causes your nipples and areolae complex to point abnormally upwards) is far less likely to occur with full submuscular placement.  Chances of developing Capsular Contracture are also thought to be even less likely with this placement.  As with subpectoral placement, the downside to this placement is also less natural movement of the breast when you flex your pectoralis muscle during normal movement or when working out.  The implants are distorted due to pressure of the flexing muscles and may give it the appearance of "jumping".

Which Implant Placement Is Right For You?
Only after a complete examination by a qualified plastic surgeon will you be able to know which placement is best for your particular case.  A common guideline on what to expect from your surgeon is if you have little to no breast tissue, you are usually recommended to have subpectoral placement.  When you have a considerable amount of natural breast tissue, or have ptosis (sag) and are not opting to get a breast lift, you are usually recommended the subglandular placement.  However, since not all surgeons offer or agree with the Full Submuscular approach, you may not even be offered this placement at all, or find that your surgeon is opposed to it altogether.  This is why it is important to have a few consultations with different board certified plastic surgeons.   This will allow you to receive different opinions with different accompanying bedside manners.  If you limit yourself to one consultation, you are denying yourself the choice.