Length of Time Breast Implants Last?

To give the user a really quick answer, "No, you should not be concerned simply because it's been over 30 years since you've gotten your implants."
Now let me explain what their concern is, and also where this worry comes from . . . 
Breast implants do NOT expire.
There are many myths surrounding this topic. The myths exist because of  medical studies that are misinterpreted in the media.
But I will say it again, breast implants do NOT expire.
If you get breast implants, one of three things can happen:
1) You may get a replacement because you WANT a change
2) You may NEED a replacement because of a complication with your implants
3) You may keep the same implants indefinitely as long as you don’t meet criteria 1 and 2
The myth of the "10 year expiration" came from studies that were done over a 10-year period. The number 10 is a long term follow-up, but in the future we’ll see 15 and 20 year follow ups.
When these studies were interpreted and published for the public (in the media and internet), they did NOT distinguish between women who WANTED to get another procedure, and those who NEEDED one.
Among those who WANTED another procedure, the reasons were varied. Some wanted larger implants. Some breastfed and wanted new implants with a breast lift. Note that getting another procedure done does not mean that they were unhappy with their results. In a 10-year period, your body can change and it's also possible for your preferences to change as well.
Then there were the patients who NEEDED to remove/replace their implant.
Long term, there are two complications that result in a woman needing another procedure. These are capsular contraction and the implant rupturing. (Capsular contracture is most likely to happen within the first year.) These are known and accepted risks of a breast augmentation.
Ten-year studies show that capsular contracture happens at a rate of 2% a year, and rupturing at 1% per year.
There is no way to completely avoid these risks. Some studies suggest that minimizing the chance of bacterial contamination may reduce the chances of capsular contracture.
In my practice, I reduce the chances of bacterial contamination by 1) doing the incision in the inframammary fold (breast crease) because there is higher risk of contamination going through the areola and  2) using what’s called a “Keller Funnel” to insert the implant 3) practicing “no touch technique” in which the surgeon never touches the implant and 4) using antibiotic irrigation to wash the implant pocket.
That said, the risk cannot be eliminated 100%. That's the nature of surgery. It is something you will have to accept if you decide to get a breast augmentation.
If one of these two complications happens--whether in 1 year, 10 years, or 20 years-- you may need a removal/replacement, depending on the severity. If neither complication happens, and you are happy with your implants, there is no need to have another procedure.
I hope that answers your question on breast implants expiring. It’s great that you’re doing this research. I always say that the best patients are informed patients.
Thank you for reading and best of luck on your journey!

If there are no problems then there is no cause for concern. It is a good thing to have them checked up regularly though!

Breast Implants are a man made product, they eventually wear out and leak. Just like cars do not last forever, planes fall out of the sky, trains fall off tracks, global warming the wourld is falling apart etc, etc. How long they can last is controversial; most manufacturers and plastic surgery societies say they should be changed every 10 years. I am not convinced this has to be done, being in practice over 12 years I have seen many patients with them longer and have not had any problems. If they are around 8-10 years and you have problems like capsular contracture, leaking etc then the should be changed, but if you like the way they look and feel I do not think you have to change them.