How much more can you over fill a saline implant past the maximum fill?

Depending on the manufacturer and style of saline implant, they can be overfilled from 20% to over 100% abs still maintain their shell integrity.  Mentor implants have the most overfill capacity since their implant  shells are more pliable but just as strong as a thicker/ stiffer Allergan/ Natrelle Implant.  The best thing to do is to have a consultation and see what really is the best option for you.  I hope this helps.

Hi Xmm, Implants can be overfilled up to about 20%. If you want larger breasts, you should consider getting a larger implant. Also, it would be best to visit your plastic surgeon for proper assessment. Only after a thorough examination you will get more information and recommendations.
Daniel Barrett, MD, MHA, MS

Certified, American Board of Plastic Surgery

Member, American Society of Plastic Surgery

Member, American Society of Aesthetic Plastic Surgery

Thank you for sharing your excellent question.  Most physicians overfill saline implants in order to cut down on rippling through the skin and typically this is in the 10-20% of recommended values.  At your current size I would exchange your implants for a larger size to achieve the look you are interested in.  Hope this helps.

Filling a saline implant with a greater volume reduces rippling and decreases the diameter of the implant allowing for more volume at a reduced diameter.  I usually fill to the recommended max, but many other plastic surgeons I have worked with have overfilled.  There have not been any cases of manufacturer warranty issues of which I am aware.

fill it to your satisfaction knowing that rupture risks will increase as you fill more.  You said you don't mind the firmness so that is not an issue but it could produce chest wall irregularities.  The more prudent thing to do is get a larger implant that has an intact warranty so you're covered for deflations and failures down the road.

While it is possible to keep filing it, at some point it will look and feel unnatural. You should consider getting a larger implant.

Thank you for the question.   
Some general thoughts regarding overfilling saline breast implants may be helpful to you: 
Saline breast implants are usually filled within a range provided by the breast implant manufacturer. Utilizing saline volumes in the UPPER range of the manufacturer's recommendations helps cut down on concerns such as breast implant rippling. Sometimes, patients who are looking for a certain "round, fake look" benefit from the use of overfilled saline implants.  This involves filling the saline implants past the range provided by the manufacturer.  I have found, through significant experience, that for the appropriately selected patient,  very nice outcomes can be achieved safely.  I have also found that saline breast implants can be overfilled significantly past what your current implants are filled to, without an increased rate of deflation.  Of course, the use of overfilled saline breast implants does have some potential drawbacks such as a firmer feel.  Furthermore, careful patient selection is key; not every patient is a good candidate for "extra-large" breast augmentation. I hope this helps.

The traditional guideline for overfilling a saline implant is about 20%, which you have far passed already. Implant volumes of 800 and 830cc are very high already and without seeing photos, I think you should consider the potential long-term complications of stretching out your tissues and the weight of the implants leading to sagging over time.