Quantitative analysis of Cytokeratin 19 expression in Odontogenic Keratocyst,Dentigerous cyst and Radicular cyst

Introduction: Odontogenic cysts and tumors arise from the enamel organ or rements of dental epithelium after odontogenic progression completes.Odontogenickeratocyst will have high recurrence rate when compared with other odontogenic cysts. To evaluate proliferation in odontogenic cysts with Cytokeratin 19 marker. Aim&Objectives: The aim of this present study is to analyze the cytokeratin 19 expression in the epithelium of the odontogenic keratocyst(OKC) and to compare it with dentigerous cyst(DC) and radicular cyst(RC). Materials and methods: The present study was carried out using the histological sections of odontogenic lesions which were selected from the archives of the Department of Oral and Maxillofacial Pathology, SIBAR Institute of Dental Sciences, Guntur. Each group has 10 archival blocks been taken and routine hematoxylline and eosin staining was performed for confirmatory diagnosis. Later immunohistochemistry was performed using CK-19 antibody. The expression of CK-19 is assessed in basal, suprabasal and superficial cells of OKC, DC and RC.  CK-19 positive cells were counted under oil immersion lenses and number of cells showing positivity was counted among a total of 100 cells counted all together in five different fields. Data analysis was done using Kruskal Wallis ANNOVA test. Results: It has been observed that the highest positivity of 64.9% is shown in DC and the positivity is seen in basal, suprabasal and superficial layers. RC showed a positivity of 58.4% and this positivity is greater in suprabasal layers compared to basal and superficial layers. OKC show only 13.5% positivity and this positivity is seen in superficial layers. Conclusion: CK 19 expression correlates with the degree of differentiation of the epithelium. So the cysts with a well-differentiated epithelium (RC and DC) express CK19, while the cysts with a less well-differentiated epithelium (OKC) show slight positivity. Thus it can be useful to differentiate OKC from DC and RC.