Dental According to the International Organization for Standards (ISO) refinements 3950 to the FDI system, 05 refers to: A Upper right sextant B Upper left sextant C Lower right sextant D Lower left sextant 💡 Explanation According to the International Organization for Standards (ISO) refinements 3950 to the FDI system, 05 refers to: ✓ Correct Answer: B. Upper left sextant