Fig. 2. Vertical linear measurements used exclusively in this study: 1, Po to palatal plane; 2, Ar to palatal plane; 3, S to palatal plane (posterior component of the maxilla); 4, Ptm to palatal plane; 5, Or to palatal plane; 6, N to palatal plane (anterior component of the maxilla).
See
Figure 1 for definition of each landmark.
