Wire ligatures should be twisted and cut leaving how long of a pigtail?

The correct choice indicates that wire ligatures should be twisted and cut to leave a pigtail length of 4-5 mm. This length is optimal for ensuring the ligature is secure while also minimizing the risk of irritation to the patient's soft tissues. A pigtail that is too short may lead to the ligature loosening over time, jeopardizing the stability of the orthodontic appliance and potentially causing discomfort for the patient. Conversely, a pigtail that is excessively long could pose a risk of impinging on the oral mucosa or becoming a source of irritation. The 4-5 mm length strikes a balance between these considerations, allowing for effective anchorage while maintaining patient comfort and safety. Proper technique in leaving the pigtail at this length is a crucial skill for dental assistants in maintaining effective orthodontic care.