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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
The Y-axis is also known as growth axis because
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The correct answer is  Y-axis
It is also called as growth-axis angle, measured as the posterior inferior angle on S–Gn–FHP. The Y-axis indicates the degree of downward and forward position of the chin in relation to the upper face. A large Y-axis is indicative of the clockwise rotation of the mandible. Y-axis does not give an indication of the size of the lower jaw but the direction in which it is growing. Mean 59.4°, range 53°–66°.