An morphological study of qubernacular foramen (macroscopically, light microscopically and electron microscopically observation)

1.根据Hellman牙龄对食蟹猴的干头骨进行了分类，观察了四尖牙孔的位置和大小的增龄变化：(1)食蟹猴的丝弓大小：IC期，下尖牙最小(平均0.36 mm~2)，上中切牙最大(平均0.58 mm~2)。在第III期，上尖牙最小(平均为0.58 mm^2)，上中切牙最大(平均为1.67 mm^2)。(2)猴上尖牙大小随年龄增长变化较小，而上中切牙变化显著。2.用透射电子显微镜观察3月龄食蟹猴引带管上皮残留物的精细结构，以明确残留物的结构和功能。结果表明：引流管内充满结缔组织，上皮细胞束位于管中央。上皮细胞的细微结构类似于Mallassez上皮残留物：上皮细胞被基板包围，并由桥粒相互连接。在大部分切片中，仅观察到少量萎缩的上皮细胞，但在靠近牙龈粘膜的上皮细胞中，我们观察到含有肿胀的线粒体、扩张的粗面内质网和收缩的紧张丝的细胞，这些异常可能是由于细胞的退化而发生的。在结缔组织的细胞外间隙内观察到明显来自于上皮细胞的细胞碎片。另一方面，半桥粒似乎没有受到退变的影响。这些高度特异的细胞内和细胞外成分的存在表明存在一些特殊的活动，可能包括维持骨管。

1.Dry skulls of crab-eating monkey were classified by Hellman's dental age, and aging change of location and size of qubernacular foramen were observed.(1) Gubernacular foramen size of crab-eating monkey : AtICstage, lower canine was the smallest (mean : 0.36mm^2), and upper central incisorwas the largest (mean : 0.58mm^2). AtIIIAstage, upper canine was the smallest (mean : 0.58mm^2), and upper central incisor was the largest (mean : 1.67mm^2).(2) Monkey's upper canine size showed less aging change, on the other hand, upper central incisor showed remarkable change.2.Fine structure of the epithelial remnants in the gubernacular canal of a 3-month-old crab-eating monkey was examined by means of transmission electron microscopy to clarify the structure and function of the remnants. The following results were obtained :The gubernacular canal was filled with connective tissue, and strands of epithelial cells were located at the center of the canal. The fine structure of the epithelial atrands was simillar to epithelial remnant of Mallassez : The epthelial cells were surrounded by a basal lamina and joined to one another by desmosomes. In most parts of the section examined, only a small number of atrophied epithelial cells were observed : However, in the epithelial cells near the gingival mucosa, we observed cells containing swollen mitochondria, dilated rough endoplasmic reticurum, and condenced tonofilaments, which abnormalities probably occurred due to the degeneration of the cells. Cellular debris apparently derived from the epithelial cells was observed within the extracellular spaces of the connective tissue. Onthe other hand, hemidesmosomes did not appear to be affected by the degeneration.The presence of these highly specific intracellular and extracellular components suggested the existence of some speciffic activity that probably includes the maintenance of the bony canal.