Cementoenamel Junction
Also written as: CEJ — Cementoenamel Junction
The anatomical boundary on a tooth where the enamel of the crown meets the cementum of the root, abbreviated CEJ.
Full Definition
The cementoenamel junction (CEJ) is the circumferential line on a tooth marking the transition between coronal enamel and radicular cementum. It is a critical reference landmark in oral surgery documents for describing the attachment level of cysts (e.g., dentigerous cysts), the extent of periodontal bone loss, and implant depth measurements. Editors should note that 'cementoenamel' is written as one hyphenated compound adjective; 'CEJ' is the universally accepted abbreviation and should be spelled out on first use in formal documents. In some texts, the older term 'amelocemental junction' (ACJ) is encountered and may need updating.
Usage
Usage note: Hyphenate 'cementoenamel' as a compound modifier. Define CEJ at first use. Prefer 'cementoenamel junction' over 'amelocemental junction' in contemporary texts.
In Context
- "The cyst wall was found to be attached at the cementoenamel junction of the impacted lower-right wisdom tooth." — Operative report
- "Probing depth measurements are recorded from the gingival margin to the base of the pocket, not from the CEJ." — Periodontal charting guidance note