How much of a dorsal hump can be restored with revision rhinoplasty?

There are a number of techniques to restore the bridge of the nose in revision rhinoplasty. These include implants (called alloplasts). I prefer your own cartilage. Rib grafts can warp. So, as you said diced cartilage wrapped in fascia is a very good choice. More recently I have changed to shaping the diced cartilage with tissue glue called Tisseal or Evicel. It allows me to precisely shape a new implant with your diced cartilage to the size and shape we choose. 

Thank you for your question.  It is definitely possible to augment your dorsum and this can be achieved with a few different tools - your own nasal and septal cartilage, your ear cartilage, or your rib cartilage.  Depending on what was removed during the first rhinoplasty, you may not have enough nasal/septal cartilage in which case ear or rib would be a viable option.  Diced cartilage with fascia can also augment the nose using any cartilage that is available.  A more minimally invasive option would be with facial fillers to augment the dorsum of the nose, though this provides only temporary results.  I hope this helps and best wishes to you.

A concavity, or saddling, of the middle third of the nose defines the so-called saddle nose deformity. The bridge can be restored to any height, and a hump can certainly be added.  Cartilage grafting is the ideal method of restoring dorsal height.  If the saddle is small, septal cartilage can be used if it is still available.  For larger saddles, ear or rib cartilage is necessary.  Either can be carved as is or diced and wrapped in fascia. I prefer rib cartilage because of its volume and strength and carving it to precisely fashion the new bridge.