Cementoenamel Junction
Pronunciation: se-MEN-toh-ee-NAM-el JUNK-shun
The anatomical boundary on the tooth surface where the enamel of the crown meets the cementum of the root, used as a fixed reference point for measuring clinical attachment loss.
Full Definition
The cementoenamel junction (CEJ) is a critical landmark in periodontal assessment because it represents the original position of the gingival margin relative to the tooth's hard tissues. Clinicians measure clinical attachment level from the CEJ to the base of the periodontal pocket, making its accurate identification essential. On radiographs, the CEJ can guide assessment of bone loss severity. Editors encountering periodontal charts or reports must ensure this term is not confused with the 'amelocemental junction,' which is an acceptable but less common synonym. Hyphenation of the abbreviated form as 'C-E-J' is non-standard; the acronym 'CEJ' is universally preferred.
Usage
Usage note: Always abbreviated 'CEJ' (no periods, no hyphens). Distinguish from 'gingival margin,' which is a soft-tissue landmark and varies with disease, whereas the CEJ is a fixed hard-tissue reference.
In Context
- "Bone loss measured 4 mm apical to the CEJ, indicating moderate horizontal bone loss." — Periodontal diagnosis report
- "The clinical attachment level was recorded from the cementoenamel junction to the base of the sulcus using a calibrated probe." — Periodontal charting note