Can nasal septum be replaced with plastic septum?

In general, plastic in the nose can be a poor solution, particularily when replacing a structural component.  Plastic septum has a much higher infection rate and extrustion rate than autologous tissues.  Costal cartilage (rib cartilage) comes from your own body and can be removed with an incision as small as 1.5 cm along the chest.  Irradiated rib is not as good of an option as the cartilage is no longer living (cells are irradiated) and does not do well in areas of structural support but is better in areas along the bridge of the nose.  

It depends on the extent of  the reconstruction needed for your husband.  From what you have described the outside of the nose is intact yet he lacks support of the nose so it has a collapsed appearance.  There are prosthetic implants which can be placed in the nose to give it support; however, in general I would not recommend  these as the main means of support.  Large implants which provide nasal support are known to extrude over time and increase the susceptibility to infection.  Of course, you are best served with seeing plastic surgeons in your area so they can examine your husband and provide options.  Rib cartilage is a great medium for structural support of the nose in cases of nasal collapse since it is cartilage from one's own body.

Reconstruction of the nose requires developing a strong framework to build up nose.  This framework is from the use of their own cartilage- either ear, septum,or rib.  Irradiated cadaver rib can also be used.  There are silicone implants and other types of implants but there is a risk of rejection and infection that you must be aware of.  Outside skin is usually reconstructed with the patients own skin but there are various new skinproducts.  Internal lining must also be reconstructed.  I would suggest you locate a Facial Plastic Surgeon experienced in Revision Rhinoplasty or Nasal Reconstruction.

 It all depends on the size of the deficiency, is there is enough tissue around it a septal button can be placed on the existing space. If there is not enough tissue, and he failed reconstruction, he may or may not be a candidate for a second attempt. This is involved and technically and difficult surgery. If interested you may want to do some research on Doctors that specialize in this surgery, such a s Dr. Burget, in Chicago. 

Thanks for your question. It sounds like you and your husband are going through a tough time dealing with this. In my opinion you husband is much better having a reconstruction using rib cartilage. Please be aware however it does not have to be harvested from his rib, a donated cadaveric rib graft may also be appropriate. These donated grafts are typically irradiated or chemically treated to essentially remove the living cells (so as to eliminate any risk of infectious transmission), however once inserted into living tissue the grafts easily become incorporated and "alive". Either form of rib graft is likely to be superior to a prosthetic as that will always carry the risk of infection and rejection. It is a tough situation but it sounds as if you are being properly advised. Hope this helps, and good luck.