When you have a capsular contracture, can you exchange and go a little bigger? To prevent it from occurring again

This is your 3rd time dealing with capsular contracture.  By simply exchanging implants, either larger or smaller, either saline or silicone, you would not be addressing the cause of the recurring capsular contracture.  The best evidence strongly supports bacterial contamination and biofilms as a major contributor to capsular contracture.  As biofilms are extremely difficult to eradicate as long as there is a foreign body present, such as a breast implant, my recommendation to patients is to remove the implant and the capsule and do not insert another implant.  Allow 6-8 months for complete healing, during which time your body can clear the area of contamination.  Then if you wish to have new implants inserted, you will be doing in a clean pocket.  Best wishes,

Going a bit larger or smaller after a capsular contracture repair is usually not a big deal.. .......

Yes, it is often possible to use larger breast implants when undergoing revisionary breast surgery to correct encapsulation.   A change in breast implant size however will not be effective when it comes to prevention of encapsulation.   When it comes to selection of appropriate breast implant size/profile, much will depend on your physical examination (dimensional planning) and your personal goals.   Careful communication of these goals with your plastic surgeon will be key.Both saline and silicone gel breast implants are good implants; each associated with pros/cons. In my practice, the type (saline versus silicone gel) of breast implant utilized is individualized mainly depending on the patient's starting anatomy and goals.  The type of implant used may determine the final outcome, especially if the patient does not have significant covering breast or adipose tissue. For example, some surgeons feel that silicone implants have a more natural look and feel than saline implants because silicone gel has a texture that is similar to breast tissue. In other words, if a patient has very low body fat and/or very little breast tissue, the silicone gel implants may provide a more "natural" result (with less potential for breast implant rippling/palpability).
 I find that most patients who undergo revisionary breast surgery (involving conversion of breast implant type), tend to exchange saline to silicone gel breast implants, not the other way around.
In my practice, I have found the most success treating encapsulation problems utilizing techniques such as sub muscular pocket conversion (if relevant), capsulectomy, use of fresh implants, and the use of acellular dermal matrix. Acellular dermal matrix is a biologic implant that carries the ability to become integrated into native tissue. It is made by taking a full thickness section of skin from a donor source (his human, porcine, or bovine in origin).
   Best wishes for an outcome that you will be very pleased with.