This current study aims to clarify the relationship between the occurrence of Entamoeba gingivalis infection and the specter of gingivitis & chronic periodontitis among Egyptian patients in comparison to healthy volunteers as a control group.

Three groups will be included in the current study. 40 Plaque samples will be collected from gingivitis patients (group 1), 40 from chronic periodontitis patients (group 2) plus 40 samples from healthy volunteers (group 3). Diagnosis of parasitic stages will rely on direct microscopic detection using permanent stains, Trichrome stain and haematoxylin and eosin stain in addition to direct wet mount examination.

Inclusion Criteria:

• Chronic Gingivitis patients with signs of clinical inflammation with no clinical attachment loss.
• Chronic Periodontitis patients having probing depth of ≥3 mm and clinical attachment level ≥ 1 mm.
• The control group: healthy subjects who attend the restorative dental clinic and had clinically healthy gingiva.

Exclusion Criteria:

• Patients with any systemic diseases

Gingivitis & Chronic periodontitis patients will be selected from the outpatients Clinic, Department of Oral Medicine, Periodontology and Diagnosis, Faculty of Dentistry, Fayoum University. Clinical examination for all patients will be performed including the following periodontal parameters: plaque index, gingival index, probing depth, and clinical attachment level. These measurements will be recorded by a single calibrated expert examiner at six sites for all teeth (mesiobuccal, mesiolingual, midbuccal, distobuccal, distolingual, and midlingual). PI is assessed by measuring the presence or absence of supragingival biofilm with a sweeping movement of the probe around the surfaces of all teeth