Sarnat B G, Selman A J
J Anat. 1977 Nov;124(Pt 2):469-74.
Two radiopaque implants were inserted into each (left and right) frontal bone in five female rabbits. Ventrodorsal cephalometric radiographs were then taken in a specially designed head holder at 6 and 16 weeks of age. From these radiographs separate tracings were made on matte acetate paper of the left and right snout including the radiopaque implants. Since the implants maintained the same relationship to each other in each frontal bone, they served as stable reference sites. The markers of the 16 weeks tracing were superposed on the markers of the 6 weeks tracing. The difference in the two established outlines of the snout represented the changes in size and shape in two dimensions that had occurred during the 10 weeks period. The mean increase was 17.91 mm at the distal (anterior) border, 4.95 mm at the lateral border, and 1.22 mm at the medial border. Thus, growth at the lateral border of the snout was about 3 1/2 times that of the lateral border.
在五只雌性兔子的每只（左和右）额骨中植入了两个不透射线的植入物。然后在6周龄和16周龄时，将兔子放在特制的头部固定器中拍摄腹背位头颅X线片。从这些X线片上，在磨砂醋酸纸上分别描绘出左右口鼻部，包括不透射线的植入物。由于植入物在每个额骨中相互之间保持相同的关系，它们作为稳定的参考点。将16周描绘的标记叠加在6周描绘的标记上。两个确定的口鼻部轮廓的差异代表了在10周期间二维尺寸和形状的变化。远端（前部）边界平均增加17.91毫米，外侧边界增加4.95毫米，内侧边界增加1.22毫米。因此，口鼻部外侧边界的生长约为内侧边界的3.5倍。
