Dental The CPITN probe has a ball end of which diameter & marking at what level: A 0.5 mm diameter ball and marking at 3,5,8 and 11.5 mm. B 1.0 mm diameter ball and marking at 3.5, 5.5, 8.5 and 11.5 mm. C 0.5 mm diameter ball and marking at 3.5, 5.5, 8.5 and 11.5 mm. D 1.0 mm diameter ball and marking at 3,5,8 and 11.5 mm. 💡 Explanation The CPITN probe has a ball end of which diameter & marking at what level: ✓ Correct Answer: C. 0.5 mm diameter ball and marking at 3.5, 5.5, 8.5 and 11.5 mm.