This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
[{'content': 'Peripheral flange is seen in which implant form? \nSelect and explain. \nA. Subperiosteal implant, B. Extraoral implant, C. Disc shaped implant, D. Root form implant', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Extraoral implants has peripheral flange for increased surface area for better osseointegration and retention.', 'role': 'assistant'}]