Dental During activation of a scaling instrument, the facial surface of the blade and the tooth surface should form an angle of A > 15 but < 45 B > 30 but < 60 C > 45 but < 90 D 90 but < 180 💡 Explanation During activation of a scaling instrument, the facial surface of the blade and the tooth surface should form an angle of ✓ Correct Answer: C. > 45 but < 90