What do orthodontists use to put on braces?

For Comfort?: If I am understanding your question correctly, orthodontists provide/ dispense comfort wax to put on the fixed braces to prevent them from cutting or jabbing into your cheeks and gums during the initial stages of treatment. This can be plane or flavored. With clear aligners an orthodontist can provide whitening gels to simultaneously whiten teeth or a remineralizing paste to strengthen the enamel.

Acrylic materials: Most of the bonding materials are similar to each other. They are usually some type of acryic, like the material used to bond on fake nails. The first chemical is some type of mild acid to condition the tooth surface. The second a clear resin which attaches to the tooth and the paste on the back of the bracket making a chemical sandwich under the bracket and attached to the roughened tooth surface.

Composite adhesives: Most commonly, orthodontists today use composite adhesives (like those the dentist uses to fix your front teeth) to hold braces to the front surfaces of your teeth. These adhesives are designed specifically for this purpose.

Orthodontists use training, skill, experience, and space age composite bonding material similar to the composite used to hold the heat shield tiles onto the space shuttle. It's very similar to the filling materials your General Dentist uses to repair a tooth damaged by decay..