Sulik K K, Schoenwolf G C
Scan Electron Microsc. 1985(Pt 4):1735-52.
The craniofacial region has a complex developmental history. Some of the major morphogenetic events of this region are described for the mouse embryo, as revealed by the use of scanning electron microscopy. The three germ layers, the primitive building blocks of the embryo, are delineated during gastrulation. During neurulation, the outer ectodermal layer gives rise to the nervous system. Several other events occur concomitantly with neurulation. These include regional subdivision of the mesoderm, body folding, turning, and formation of the heart and gut. The craniofacial region, as well as a number of other regions or organ systems, undergoes major developmental events during the phase of embryogenesis called organogenesis. The visceral (branchial) apparatus develops around the primitive oral cavity and pharyngeal region of the foregut, and gives rise to many of the structures of the head and neck. The face develops from the first visceral arches and derivatives of the frontonasal prominence. The tongue also originates from tissue prominences derived from the visceral arches. The oral and nasal cavities are initially continuous broadly with one another. As a result of partitioning, paired nasal cavities develop and become largely separated from the underlying oral cavity. Scanning electron microscopy reveals much about the morphological events occurring during formation of the craniofacial region. However, emphasis in future studies should be placed on determining the underlying cellular and molecular mechanisms causing these events.
颅面部区域有着复杂的发育历程。利用扫描电子显微镜揭示了该区域一些主要的形态发生事件，这里描述的是小鼠胚胎的情况。胚胎的三个胚层，即胚胎的原始构建模块，在原肠胚形成过程中被勾勒出来。在神经胚形成过程中，外层的外胚层产生神经系统。还有其他一些事件与神经胚形成同时发生。这些事件包括中胚层的区域细分、身体折叠、扭转以及心脏和肠道的形成。颅面部区域以及许多其他区域或器官系统，在胚胎发育的器官发生阶段会经历主要的发育事件。内脏（鳃）器围绕原始口腔和前肠的咽部区域发育，并产生头部和颈部的许多结构。面部由第一对内脏弓和额鼻隆起的衍生物发育而来。舌头也起源于来自内脏弓的组织隆起。口腔和鼻腔最初在很大程度上是彼此连续的。由于分隔，成对的鼻腔发育并在很大程度上与下方的口腔分离。扫描电子显微镜揭示了颅面部区域形成过程中发生的许多形态学事件。然而，未来的研究应着重于确定导致这些事件的潜在细胞和分子机制。
