Some problems associated with the long face syndrome:
(1) excessive eruption of the posterior teeth
(2) excessive eruption of the anterior teeth
(3) short posterior facial height
(4) steep mandibular plane angle
Landmarks on lateral skull radiographs to be identified:
(1) S: sella (mid-point of sella turcica)
(2) N: nasion (most anterior point on the frontal nasal suture)
(3) Go: gonion (most posterior inferior point on angle of mandible)
(4) Gn: gnathion
(5) Me: menton (lowermost point on the mandibular symphysis)
Criteria for diagnosis of long face syndrome:
(1) angle of the gonion-to-gnathion line and the sella-to-nasion line: >= 37 degrees
(2) (sella-to-gonion length) to (nasion-to-menton length) ratio <= 0.65