How many types of self-ligating brackets are described?

• A. 2
• B. 3
• C. 4
• D. 5

Answer: (B)

Self-ligating brackets are categorized by how the built-in ligature mechanism interacts with the archwire. Three types are commonly described: passive self-ligating brackets, where the clip or door simply closes over the wire without pressing on it; active self-ligating brackets, where the clip actively presses against the archwire, increasing contact and friction; and semi-active (also called interactive) self-ligating brackets, where the mechanism partially engages the wire to provide some resistance but not full pressure. This three-way classification captures the main ways these systems control wire engagement and clinical force transmission, even though some newer designs may blend features.