This is a case treated with DAMON® brackets in the lower arch and Sinergy® brackets in the upper arch.
Self-ligating brackets were popularized by Dr. Damon worldwide. We can see how, in this case, we open space for a lower incisor that, in the model of the arch, is absolutely collapsed and located in second line with respect to the rest.
In the upper arch we use a type of low-friction brackets, Sinergy® brackets, which do, on the contrary, have elastic ligatures.
But the really important thing is how happy the patient ended up!