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
Peripheral flange is seen in which implant form? 
Select and explain. 
A. Subperiosteal implant, B. Extraoral implant, C. Disc shaped implant, D. Root form implant
B: Extraoral implant
Answer: B: Extraoral implant 
Explanation: Extraoral implants has peripheral flange for increased surface area for better osseointegration and retention.