In a periodontal case with gingival recession, probing depth, and bone loss, calculate the clinical attachment level (CAL). Recession is -1mm, pocket depth is 4mm. What is the CAL?

Correct answer: C. 5mm

• A. 4mm is the pocket depth alone without adding recession.
• B. 3mm does not correctly account for both recession and pocket depth.
• C. Correct. CAL = Probing depth + Recession (when CEJ is apical to the gingival margin). CAL = 4mm + 1mm = 5mm. When recession is present (gingival margin is apical to CEJ), recession is ADDED to pocket depth to calculate CAL.
• D. 8mm would be an overestimate not supported by the given values.