RESUMEN
Oral mucosa is subjected constantly to external and internal stimuli that can give rise to reactive lesions. These lesions are non- neoplastic in nature. They manifest a spectrum of diseases that range from developmental, inflammatory, and reactive to neoplastic changes. Reactive lesions are typically gives response to chronic inflammation caused by various forms of low grade chronic irritations to the oral mucosa such as dental plaque and calculus, sharp edges of grossly carious teeth, faulty dental restorations, chronic biting habits, ill-fitting dental/oral appliances and food impactions. These lesions have a very similar appearance to benign neoplastic proliferations. This similarity is troublesome in differential diagnosis among them. Different types of localized reactive lesions of oral cavity are focal fibrous hyperplasia (FFH), pyogenic granuloma (PG), irritational fibroma, peripheral giant cell granuloma (PGCG), peripheral ossifying fibroma (POF), fibro-epithelial hyperplasia/polyp, inflammatory fibrous hyperplasia, and inflammatory gingival hyperplasia.