The diagnosis and management of severe periodontitis in young individuals is often challenging. Oral and periodontal manifestation may be the first sign of underlying systemic diseases and careful multidisciplinary approach in diagnosis and management is of great importance for a better overall outcome. Gingival biopsy is a mandatory simple and reliable investigation to rule out systemic causes when severe periodontal destruction noted in young.

In this case report, we present a young adult male who presented with severe periodontitis, which showed poor response to conventional periodontal treatment, later confirmed as Langerhans cell histiocytosis, a rare neoplastic disorder.