Clinical Attachment Level is defined as the distance from the CEJ to the base of the periodontal pocket.

• A. Base of pocket
• B. Gingival margin
• C. Cemento-enamel junction
• D. Pulp chamber

Answer: (A)

Clinical Attachment Level measures how much the periodontal support has been lost around a tooth. It uses the cementoenamel junction (CEJ) as a fixed starting point and the base of the periodontal pocket as the endpoint. This makes CAL a reliable indicator of attachment loss, even when the gingival margin moves due to recession or inflammation.

The correct idea is that CAL equals the distance from the CEJ to the base of the pocket, because the CEJ provides a stable reference, while the pocket base reflects where the attachment apparatus ends. The gingival margin is variable with inflammation or recession and would not consistently represent attachment loss. The CEJ itself is the reference point, not the measurement endpoint, and the pulp chamber has no role in measuring periodontal attachment.