• Papilloma is characterized by finger-like projections lined by hyperplastic stratified squamous keratinized epithelium.
• Each finger like projection has a central thin connective tissue core carrying the blood vessels.
• Histopathologically, leukoplakia is characterized by Hyperkeratosis, Acanthosis and Dysplastic features.
• Dysplastic features include bulbous or drop shaped rete ridges, basal cell hyperplasia, loss of polarity of basal cells, irregular epithelial stratification, cellular pleomorphism, alteration in nuclear cytoplasmic ratio, nuclear hyper chromatism and increased mitosis.
ORAL SUBMUCOUS FIBROSIS
• The epithelium is atrophic with short or flat rete ridges.
• Connective tissue shows juxta epithelial hyalinization and exhibits fibrosis with dense bundles of collagen fibres.
• Focal collections of chronic inflammatory cells are present.
• In severe cases, muscles undergo degenerative changes.
SQUAMOUS CELL CARCINOMA
• The most significant microscopic feature of squamous cell carcinoma is dysplastic epithelial cells invading connective tissue.
• These cells may be arranged in the form of cords, sheets or islands.
• Dysplastic features seen are hyperchromatism of nuclei, alteration of nuclear cytoplasmic ratio, pleomorphism of cells and nuclei, prominent nucleoli, many normal and abnormal mitotic figures, individual cell keratinization and keratin pearl formation.
Source: Maji Jose