This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Papulosquamous disorders, Subject name: Dental
Max. Joseph&;s space is a histopatho-logical feature of - 
Select and explain. 
A. Psoriasis vulgaris, B. Lichen planus, C. Pityriasis rosea, D. Parapsoriasis
B: Lichen planus
Answer: B: Lichen planus 
Explanation: Lichen planus in histopathology shows thickened granular layer , saw toothing of rete ridges , basal cell degeneration ( leading to Max Joseph s spaces and colloid/ Civatte body formation) and a band like upper dermal infiltrate of lymphocytes. IADVL TEXTBOOK OF DERMATOLOGY PAGE 1070