This is a very reasonable question, and my answer will be a bit different from most of my colleagues' replies. Let's start at the beginning--much of what is written in the plastic surgical literature and implant manufacturers' studies is based on old data with previous generations of breast implants. Many different implant types by many different manufacturers placed in unique patients by surgeons with vastly differing training, techniques, biases, habits, and skills. And if the implants are saline, some surgeons refuse to (properly) "over" fill the implants to reduce rippling and creasing that can lead to premature shell fold failure, leak, and deflation.
Another sorry fact is that the statistics about breast implants include data from non-plastic surgeons who (perhaps legally, but inappropriately) put implants in gullible women who allow them to do this without the "cosmetic surgeon" having completed full plastic surgery training and American Board of Plastic Surgery certification. Lots of variables mean lots of (poor) outcomes, all of which are included in the data set!
All 3 present implant manufacturers in the USA have lifetime free replacement of defective or ruptured implants (saline AND silicone). They also pay for the surgical costs of replacement for the first 10 years after initial implantation--THIS is where the urban myth of "wearing out" after 10 years arose, not because they need to be replaced at that point.
Another interesting aside--I have had saline implant patients who present with deflation and decide they want different implants (switch to silicone, or sometimes just different-sized saline implants). When I examine the implants in the operating room, I have found more than one patient with several pinholes in their implant (I counted 7 in one implant) indicative of self-puncture. Yes, they decided to take "advantage of" the implant company's generous free implant replacement and surgical fee coverage (for the first 10 years) by poking their implant with a needle to cause it to leak and "need" replacement. The telltale giveaway--it only takes one hole to get an implant to leak to deflation, but it does so much more gradually than patients think. They somehow believe that if they stick their implant it will deflate like popping a balloon. When it doesn't, they are both committed and determined, so they poke enough times to finally get it to deflate more rapidly, but also giving themselves away. And the company still has to report it to the FDA as a "leak."
But I digress. I tell my patients that if they believe in a Creator who made mankind in HIS/HER image, humans are imperfect and do not last forever.
Implants made by man must be somewhat less "perfect" than God's creations, so they too should never be said to "last forever."
But careful surgery leading to proper position and a soft, pliable capsule around the implants will yield breasts that are soft, natural, and will likely last as long or longer than most of us humans. Of course our tissues age and sag, and we gain and lose weight, and breast feeding causes many unanticipated breast changes (with or without implants).
Statistically, the most-commonly reported reason for re-operation after breast augmentation nationwide is still capsular contracture. In our practice, my partner and I do several hundred breast augmentations each year, and our capsular contracture rate is about 2-3% with the present generation of cohesive gel implants. We do use saline implants, but in a very small minority of patients, as we firmly believe that the cohesive silicone gel implants in use by all 3 US companies are superior in natural soft "feel" and cannot leak, or deflate. Rupture is nearly impossible as well.
In our practice, the most common reason for re-operation is "I want to go bigger," not "I have this problem." This too gets reported in the statistics of re-operations during a lifetime. A bit misleading, don't you think?
I believe a carefully-performed breast augmentation requires only "protection" of the imlants whenever a bacteremia (bacteria in the blood stream) is caused, such as dental work or cleanings. I ask my patients to take a dose of antibiotic the night before and two hours before dental work, just in case there might have been a minor breast bump or injury (unnoticed, in most cases) that could allow bacteria to enter the space around one of her implants, stimulating a bacterial biofilm and development of capsular contracture. Other than that, the good results I achieve in the vast majority of my patients requesting breast enlargement require no maintenance, no periodic MRI scans, and truly do last a lifetime.
Guarantees, of course not. Most people don't even live in the same house their whole lives; we certainly get new cars every few years or so. Our bodies change and so do our attitudes about breast size, perkiness, and aesthetics. These are the main reasons to change implants, not because they are inherently "faulty," "risky," or guaranteed to need replacing every 10 years. Just because you may have other medical issues later in life is no reason to avoid breast implants if you wish to have them now. Just choose an ABPS-certified plastic surgeon who does lots of breast surgeries and has the personal ethic to "do it right" each and every time. Best wishes! Dr. Tholen