DeepDyve Craniofacial development, by G. Sperber Craniofacial development, by G. Sperber Cunningham, Michael L. Geoffrey Sperber are a remarkable compilation of the basic embryology, biology, and malformation of human craniofacial structures. This organization allows the reader to review the current knowledge of the basic principles of embryogenesis, in order to apply these principles to the development of craniofacial structures. Each chapter outlines development from embryogenesis to the mature form, and gives examples of malformations that underscore the developmental pathogenesis.
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Development of the tongue A. The tongue buds are then invaded by occipital myoblasts that form the intrinsic muscles of the tongue.
Intrinsic musculature is also derived from occipital myoblasts. Development of the skull anterior portions viscerocranium are derived primarily from neural crest mesenchyme that develop into bones via membranous ossification bones in the floors of the cranial fossae, aka the "chondrocranium" cribriform plate, sphenoid, petrous temporal and clivus of the occipital , are derived from paraxial somitic mesoderm that develop bone via endochondral ossification flat bones of the cranial vault, aka the "neurocranium" e.
Because the brain continues to grow in size up until years of age, premature fusion of the sutures or fontanelles will result in abnormal shaping of the head as the brain will cause displacement of the bones that remain unfused. Development of the face initially formed by 5 mesenchymal swellings aka processes or prominences : 2 mandibular prominences right and left, from 1st arch neural crest mesenchyme 2 maxillary prominences right and left, from 1st arch neural crest mesenchyme frontonasal prominence midline structure, from cranial neural crest mesenchyme two nasal pits develop in the ventrolateral aspects of the frontonasal prominences, thereby forming 2 lateral and medial nasal prominences development of the face occurs via the growth and fusion of these prominences: the mandibular prominences grow together to form a single mandible The maxillary prominences shown in orange below grow toward the midline and fuse with the lateral nasal prominences blue.
A deep groove called the nasolacrimal groove forms between the maxillary and lateral nasal prominences on either side of the developing nose. Most of the groove is obliterated with fusion of the maxillary and lateral nasal prominences, but a small portion persists as the nasolacrimal duct and lacrimal sac. Inward growth of the maxillary prominences also causes them to fuse with the medial nasal prominences yellow.
Continued growth of the maxillary prominences combined with regression of the frontonasal prominence pushes the two medial nasal prominences together such the medial prominences eventually fuse to form the midline of the nose and philtrum of the upper lip —the superior portion of the frontonasal prominence grows and extends to form the forehead whereas the inferior portion does not grow very much, thus allowing the medial nasal processes to fuse in the midline.
Below is a summary of the contributions of the prominences to the adult face: Disruption of the development of any of the facial prominences can result in a variety of facial anomalies, such as from left to right in figures below : hare lip bilateral failure of maxillary and medial nasal prominences to fuse oblique facial cleft unilateral failure of maxillary, medial, and lateral nasal prominences to fuse macrostoma incomplete lateral merging of maxillary and mandibular processes median cleft lip incomplete fusion of medial nasal prominences frontonasal dysplasia hyperplasia of inferior frontonasal prominence, thus preventing fusion of the medial nasal prominences VI.
Development of the palate A. Primary palate forms via the fusion of the two medial nasal prominences in the midline of course, this midline fusion is driven via growth of the maxillary prominences which pushes the nasal prominences toward to the middle consists of the premaxillary segment of the maxilla, which contains the four incisors and the incisive canal B. Secondary palate forms via outgrowths of the maxillary prominences called the palatine shelves initially, the palatine shelves project on either side of the tongue.
With growth and expansion of the mandible the tongue moves down, allowing the palatine shelves to grow toward the midline and fuse to form the secondary palate, which consists of the palatine segment of the maxilla and palatine bone. Complete fusion of the primary and secondary palate is a complex process involving growth of the component tissues, epithelial to mesenchymal transformation, cell migration, and programmed cell death at fusion sites —disruption of any part of this process can result in cleft palate.
Given the involvement of the maxillary and nasal prominences, cleft palate is often but NOT always accompanied by cleft lip.
In craniofacial development, paraxial mesoderm contributes to which of the following? NONE of the above E. The craniofacial defect illustrated in the figure below was most likely caused by which of the following?
Craniofacial Embryogenetics and Development
Sperber; Steven M. Its origin dates back to the four editions of its predecessor Craniofacial embryology, which was first released in In , Professor Geoffrey H. Sperber partnered with his son, Dr Steven Sperber, a clinical geneticist, to develop the Craniofacial embryogenetics and development series, which have since been employed throughout the world as a primary teaching resource. We have experienced a substantial amount of progress in the field of embryology within the last decade, since the second edition of this book was originally published. On entering its third edition, the integration of modern genetics with embryology has enabled the creation of a more relevant and advanced text. The book is well-structured, and the content can be easily navigated, as it is split into two main sections with 20 chapters.
Craniofacial development, by G.H. Sperber
The insights of genetic expression in determining the unfolding of the embryonic layers have revolutionized our understanding of some of the mechanisms of embryogenesis. As implied by the title of the third edition, Craniofacial Embryogenetics and Development, genetics is linked with embryology in this text. Virtually all embryological development has an underlying genetic component, and the basic science of genetics is the key in uncovering the many mysteries of embryogenesis. The tools of molecular genetics have provided insights into developmental mechanisms that allow us the ability to identify transient regions of genetic expression patterns. Unraveling the precise biochemical and mechanical interactions of discrete regions in the unfolding embryonic components remains a dauntingly complex challenge to understanding the conversion of the genome into the phenome. The addition of genetic information gleaned from other mammalian species might aid in dissecting human embryology into comprehensible components to understand normal and abnormal development.