This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hypo Pigmentary Disorders, Subject name: Dental
[{'content': 'True about vitiligo are all except: \nSelect and explain. \nA. Surgical treatment is indicated if medical treatment fails, B. Leucotrichia is associated with good prognosis, C. Autoimmune condition, D. Skin biopsy specimen shows abscence of melanocytes.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: VITILIGO -Autoimmune disorder -Skin biopsy specimen shows absence of melanocytes. Poor prognostic factors: Leucotrichia Long standing type Lesions over bony prominences Acrofacial -Surgical treatment is indicated if medical treatment fails and disease is stable for >1 year. - Modalities : Skin grafting Non-cultured autologous melanocytic transfer Cultured autologous melanocytic transfer.', 'role': 'assistant'}]