Linear gingival erythema (LGE) is a periodontal disorder diagnosed based on distinct clinical characteristics.
It was originally thought that LGE was directly associated with HIV, and it was thus called HIV-associated gingivitis (HIV-G).
Later research confirmed that LGE also occurs in HIV negative immunocompromised patients, and it was thus renamed.
[1] LGE is limited to the soft tissue of the periodontium, appearing as a red line 2–3 mm in width adjacent to the free gingival margin.
Unlike conventional periodontal disease, though, LGE is not significantly associated with increased levels of dental plaque.