The aim of the present study was to evaluate the oral status in a group of institutionalized individuals from Craiova, a city in South-Western Romania. Also, another objective of the study was to highlight the clinical, histological and immunohistochemical (IHC) aspects of periodontal disorders in the elderly. The study was performed on 48 institutionalized individuals examined in the Clinic of Dental Prosthetics, Faculty of Dentistry, University of Medicine and Pharmacy of Craiova, Romania, in 2013. The data were collected using medical records and intraoral clinical examination. The data were processed by descriptive statistical analysis. The gingival mucosa samples were harvested from subjects with teeth mobility. The gingival fragments collected were processed through the histological technique of paraffin inclusion. The serial sections were commonly stained with Hematoxylin-Eosin and processed by the IHC technique with anti-CD3, anti-CD45RO and anti-CD20 antibodies. Of the 48 study participants, 20 were males, 28 were females, aged over 56 years old. 66.6% of them had poor oral hygiene, with a mean simplified oral hygiene index (OHI-S) of 1.57, 16 had the generalized periodontitis, three experienced some form of gingival overgrowth at the remaining teeth caused by incorrect fixed prosthesis, and 25 participants presented a form of periodontitis with gingival retraction. Gingival mucosa samples were histologically diagnosed with papillomatosis with discrete parakeratosis and rich chronic inflammatory infiltrate. The IHC reactions for the studied antibodies were different for T- and B-cells, which had different disposition in lamina propria.