What is the Imagination arch wire tooth colored coating made of?
The material is called Epoxy and it adds .002 inches to the raw wire size
Why do you need aesthetic brackets (Phantom) on the lingual side?
If you wear lingual metal brackets you will see a gray shade through the teeth especial on the lower jaw. When you get older you naturally get thinner teeth and a metal lingual bracket will be more visible.
Instructions of use for Smartbond, when we want to bond a bracket on porcelain crown?
I would suggest that you roughen up the porcelain crown with a diamond bur and refrain from using any etching.
Do your composite brackets discolour after a couple of month?
Our experience with discoloring due to food etc. is usually non-existing.
The prime cause is the adhesive that goes yellow over time. However, hygiene is a very important factor and instructions to the patients are of major importance (that goes for all aesthetic brackets).