Diewert V M, Lozanoff S
Department of Clinical Dental Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, Canada.
J Craniofac Genet Dev Biol. 1993 Jul-Sep;13(3):162-83.
Although it is recognized that morphology of the craniofacial complex changes during primary palate formation, little information is available about the sites and amounts of growth in different regions. The purpose of this study was to analyze growth patterns of human embryonic heads in frontal sections and to identify regional growth associated with changes in craniofacial morphology and formation of the primary palate. Photographs of frontal sections of 31 human embryos of stages 16 to 19 from the Carnegie Embryology Collection were selected at seven different planes through each head, enlarged and traced, and landmarks were located for computerized morphometric measurements and for finite element modeling (FEM) analyses. Anatomical form change from the initial geometry of the average early stage 16 group to that of later stages was shown by numerical values and graphic displays of regional growth changes during midfacial morphogenesis. Between stages 16 and 19, extensive changes in midfacial morphology occurred as the frontonasal prominence elongated vertically (height increased by seven times) and narrowed to approximately half the width, with more pronounced changes in the anterior nasal region. The brain and the face became vertically separated, and the facial prominences became more frontally positioned relative to the brain. Changes in depth of the face were very limited during this period. The area of the maxillary region increased extensively, particularly in the anterior region, as the maxillary prominences grew forward, lateral to the nasal cavity, to contribute to the primary palate. The lateral nasal prominences increased in size with a predominantly horizontal growth pattern. These patterns of vertical growth of the midfacial tissues, narrowing of the nasal pits and frontonasal prominence, forward growth of the maxilla, and relative separation of the brain and face were identified as predominant features of embryonic craniofacial growth during primary palate development.
尽管人们认识到颅面复合体的形态在原发腭形成过程中会发生变化，但关于不同区域生长的部位和生长量的信息却很少。本研究的目的是分析人类胚胎头部额状切面的生长模式，并确定与颅面形态变化和原发腭形成相关的区域生长情况。从卡内基胚胎学收藏中选取了31个16至19期人类胚胎的额状切面照片，在每个头部的七个不同平面上进行选择、放大和追踪，并确定地标用于计算机形态测量和有限元建模（FEM）分析。通过数值和图形展示了面中部形态发生过程中区域生长变化，显示了从平均早期16期组的初始几何形状到后期阶段的解剖形态变化。在16至19期之间，面中部形态发生了广泛变化，额鼻突垂直伸长（高度增加了七倍）并变窄至宽度的约一半，鼻前部区域的变化更为明显。脑和面部在垂直方向上分离，面部突起相对于脑更靠前定位。在此期间，面部深度的变化非常有限。随着上颌突向前生长，在上鼻腔外侧生长以形成原发腭，上颌区域的面积大幅增加，尤其是在前部区域。外侧鼻突尺寸增大，主要呈水平生长模式。面中部组织的这种垂直生长、鼻窝和额鼻突变窄、上颌向前生长以及脑和面部相对分离的模式被确定为原发腭发育期间胚胎颅面生长的主要特征。
