Explain the following in detail based on its etiology , clinical features, classifications , histopathological features.

write 5 pages for Pre-malignant lesions

A) Leukoplakia

B)palatal reverse smokers

C)Erythroplakia

write 5 pages for pre-malignant conditions

A) Oral submucous fibrosis

B) Lichen planus

C) Lupus erythematous

Explain the following in detail based on its etiology , clinical features, classifications , histopathological features.