FIGURE 2.

Morphometric analysis of normal maxillary prominences between stages 24 and 28. Reconstructed maxillary prominences at stage 24 (A and B) and stage 28 (C and D). Isosurfaces have been generated from segmented maxillary prominences using Amira. Ridges represent circumscribed slices. Isosurfaces are rotated to show frontal and sagittal views. E and F, at stage 24, the maxillary prominence is normally of equal size craniocaudally and medio-laterally (Cr-Ca/ML ratio is 1.19), whereas at stage 28, the maxillary prominence is three times as long (Cr-Ca/ML ratio is 3.06). The abbreviations used are as follows: ca, caudal; cr, cranial; d, distal; e, eye; fnm, frontonasal mass; l, lateral; m, medial; md, mandibular prominence; mxp, maxillary prominence; np, nasal pit; pr, proximal.