Final answer:
Option 2. is correct. Orthodontic separators are required before the placement of bands, as they create space between teeth to allow the bands to be fitted. Bands are an integral part of braces that anchor arch wires and other orthodontic appliances, aiding in teeth realignment.
Step-by-step explanation:
The use of orthodontic separators is necessary before the placement of bands. Orthodontic separators, also known as spacers, are small devices used to create a small gap between teeth before fitting the orthodontic bands. These bands are rings made of metal or other materials that encircle the teeth as part of braces to anchor other parts of the braces, such as arch wires and sometimes springs and other appliances.
Separators are positioned between the molars to push them apart slightly, thereby making enough space for bands to be applied without causing damage to the teeth. Orthodontic bands are a crucial component of braces because they provide a solid foundation for the attachments that will ultimately help in the realignment of the teeth, as can be seen in the figures referenced, where braces, including bands and wires, are used to apply forces to teeth to realign them. The separators are removed before the bands are cemented into place.