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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which cephalometric point represents the centre of ramus of mandible?
assistant
The correct answer is  Xi point:
A point located at the geometric centre of the ramus. The location of the Xi point can be found geometrically by drawing a line through the porion–orbitale (FH) and perpendicularly through the PT vertical (PTV).