What is porion point?
Porion (Po) is an anatomical landmark point for the craniofacial evaluation. It is defined as the most superior and outer bony surface point of the external auditory meatus and can be called as the anatomical Po [1].
What is porion in anatomy?
264711. Anatomical terminology. The porion is the point on the human skull located at the upper margin of each ear canal (external auditory meatus, external acoustic meatus). It lies on the superior margin of the tragus.
What is Frankfort horizontal plane?
: a plane used in craniometry that is determined the highest point on the upper margin of the opening of each external auditory canal and the low point on the lower margin of the left orbit and that is used to orient a human skull or head usually so that the plane is horizontal.
What is Tweed analysis?
Tweed suggested that a steeper mandibular plane angle as indicated by Frankfort-mandibular angle greater than 30o, results to a poor prognosis in relation to facial esthetics. Tweed believed that the incisor mandibular plane angle should range between 85o and 95o with the mean value of 90o.
Why we use Frankfort horizontal plane?
The Frankfort plane was employed for orientation of the patient and was chosen as the best anatomic indicator of the true horizontal line. It is also closely related to the natural head position (NHP) (3, 4).
What is SNA orthodontics?
SNA (sella, nasion, A point) indicates whether or not the maxilla is normal, prognathic, or retrognathic. SNB (sella, nasion, B point) indicates whether or not the mandible is normal, prognathic, or retrognathic.
What is yen angle?
Subjects with a YEN angle between 117 and 123 degrees have a skeletal Class I pattern. With an angle less than 117 degrees, patients are considered to have a skeletal Class II relationship, and with an angle greater than 123 degrees, patients have a skeletal Class III.