What must be placed before ortho bands can be seated?

Before ortho bands can be seated, separators are essential. Separators are small devices that are placed between the teeth to create space for the orthodontic bands. This space is necessary because ortho bands need to fit securely and snugly around the tooth structure. Without adequate separation, it can be challenging to properly place the bands, potentially leading to discomfort or improper seating.

In contrast, the other options do not fulfill this specific preparatory role. Pigtail clips, retainers, and brackets serve different functions in the orthodontic process but do not assist in the initial preparation of teeth for band placement. Thus, separators are crucial before the orthopedic bands can be effectively and safely positioned on the teeth.