[Noah930]

There are 2 primary ways a wound heals (for the most part): primary and secondary intention.

Primary intention is how most surgical incisions heal: the two wound edges are reapproximated (sutured together) at the end of the surgery, and they just heal together.

Secondary intent is how your wife's wound is healing. The skin edges either weren't closed or (more likely in a C-section) the skin edges dehisced--came apart. That can happen for various reasons. But when that happens, you don't want to sew the skin edges back together. You have to let the wound heal from the "inside out." So you pack the open space of the wound, as you're doing, and let the tissue underneath the skin fill in. That tissue ideally is a beefy red, lumpy tissue (called granulation tissue). Eventually the wound will granulate in and the skin edges will come together. It'll just take time. The bad part is that it'll take time, and the scar won't be as cosmetic (which can be dealt with later, if so desired).

Silver nitrate is a chemical which burns tissue. It can be used to debride (get rid of) not so healthy skin and soft tissue and allow the healthy stuff underneath to fill in. It's not discriminatory, so whatever it touches/poisons, it'll kill (healthy and unhealthy tissue, alike). Just touch it to the stuff you want to kill. A few days after application, the affected tissue will turn black or grey and come off.