Just had explant surgery. 375cc full D saline implants removed. Current size is a B.

hi cosmo17, 
your skin elasticity is predetermined and you can't do much to increase or decrease it. Overstretched skin will probably go back to "normal" over a course of few months. 
I hope this was helpful,
Dr. Daniel BarrettPlastic and Reconstructive SurgeryBeverly Hills, CA

Tight conpression brassiere may help to retighten the tissue and contract the skin as well. Otherwise there are no remedies to tighten skin of the breasts 

Your final results from implant removal are seen around six to nine months. You will notice many changes prior to this as swelling gradually decreases and the tissues relax. The amount of skin retraction you will have will depend on the size of the implants, how long they were in place, and your skin elasticity. Following your surgeon's advice, including compression, will help you achieve optimal results.

You will get the maximum results after 4 weeks. Sport bra will help to provide compression. I offer my patient fat grafting to help with the shape and size. The link shows a patient after saline implant deflation and one session of fat grafting.

The best case scenario is do deflate saline implants and then take them out after they have allowed the tissues to shrink down around them.If they are silicone then the implants are removed and the tissues are allowed to contract down around them over time.