Juvederm Ultra in short, as the name suggest, this is a Juvederm product but the molecular size is bigger due to cross linking by the disulphide bonds. It comes with the lidocaine for extra comfort for use. This give the higher visico-elasticity and tend to be more difficult to inject. It has a similar property of a Juvederm but last much longer as the name suggest. It can last as much as 1 to 2 years. This is not for the fine lines, but more for the larger fold such as the naso-labial fold and the marionette line, or glabellar line or large forehead folds. Juvederm XC (Extra comfort) can be used to fill tear trough below the eye bag as a way to remove eye bag.
Due to the larger molecules and thicker gel, the gel seldom migrate and can give a very good effect. It imbibe and hold water, stimulates the fibroblast to produce its own collagen. As the gel slowly disappear, the body collagen gets laid down into and replace the gel volume thereby continue to gives its support to the underlying skin. Dr David Ling and Dr Grace Low is well versed and has accumulated 40 years of experience injecting filler.
This is less likely due to its similar molecular structure between all the species.
It can last about 1 to 2 years.