The plastic bag is the biggest point of failure for traditional breast forms, and it often splits. I have seen recommendations for using Scotch tape or duct tape for breast repairs. Those look awful and never seem to last very long. I have found that using Tegaderm, an easily available surgical bandage made by 3M, makes solid and practically invisible repairs. You can find Tegaderm at almost any drugstore.
It's best to fix the form as soon as you notice the problem. Start by cleaning any silicone or dirt on the outside of the form. I'd avoid using water, but alcohol should be OK. Paper towels or cotton balls work pretty well for this. Then take the Tegaderm bandage and open up the outer covering. Leave it encased in the inner covering. Using some scissors, cut a piece of the appropriate length, with enough width to cover the split. Holding the breast form so that the edges of the split are as close as possible and there are no air bubbles, apply the tape. Smooth it and remove the paper top. You should have a nearly invisible repair that is amazingly tough and waterproof!
I have never had to repair a seam, but you could probably use Tegaderm for that. I would try to put two pieces of Tegaderm on each side of the seam and stick them together, then trim off the excess. If you try this, please let me know if it works.
Thanks for reading!
I hope this series has been helpful. I'm always happy to get good suggestions and nice comments. Feel free to send me a note!