Estimation of silver nucleolar organizer regions in oral lichen planus, oral lichenoid reactions and oral lichenoid dysplasia

AIMS AND OBJECTIVE: (1) To study the clinical and histological features of oral lichen planus, oral lichenoid reaction (OLR) and oral lichenoid dysplasia (OLD). (2) To estimate and compare the silver nucleolar organizer regions in OLR and OLD. MATERIALS AND METHODS: A total of 40 biopsies were studied; sections were divided as study group, which consists of OLP, OLR and OLD each of 10 cases and 10 biopsies of normal oral mucosa as control group. Sections were stained by silver staining technique and total number of silver stained nucleolar organizer regions (AgNORs) were counted in nucleoli of 100 cells in each section under x100 objective (oil immersion). RESULTS: Our study revealed that the difference between the (AgNOR) count of OLP (2.272 ± 0.09) and OLR (2.27 ± 0.073) is not statistically significant (P = 0.81). The mean AgNOR count of OLD (2.388 ± 0.043) compared to that of OLP (2.272 ± 0.09) and OLR (2.27 ± 0.073) showed an increase and it is statistically highly significant (P = 0.002 and P = 0.003, respectively). CONCLUSION: AgNOR count is an objective test, which has stronger biological basis for diagnosing epithelial dysplasia. It is easy to perform, inexpensive and is performed on biopsied specimen. However, this technique cannot differentiate OLP and OLR, as there is no much difference in the proliferative activity of cells in these two lesions. It is reasonable to suggest that all biopsy tissues from lichenoid lesions where dysplastic features are observed in routine histopathological sections should be additionally stained by silver technique to ascertain dysplastic status of the lesion. CLINICAL SIGNIFICANCE: This is an improved diagnostic parameter, which will help pathologists to formulate more definitive final histopathological diagnosis and will in turn facilitate the formulation of patient treatment and follow-up care by clinicians.