[Human cervico-facial morphogenesis. Evaluation of acquired data and current outlook. (Part 1: facial morphogenesis)]

The embryonic development of the face has been studied in many reviews, this work purposes only to clear up some points which remain obscure concerning cervico-facial morphogenesis. In the first part of this study only the facial development, properly speaking, is considered, although it cannot be separate of cervical development to which a second study will be reserved. In the present study we recall the particular aspects of the neurulation in the cephalic area, then the establishment of the facial processes. Then we approach among other things the way to consider the maxillary process with regard to the other facial processes. After is considered constitution and natured of the prechordal plate which has been diversely explained. Finally, the modelling of the face is evocated, in which the dissociation between the olfactive and buccal spheres is pointed out, with the disparition of the muzzle, as it is established in the haplorhinae, a class of primates in which the human being is involved. This phenomenon raises different questions, in particular about the relation of this disposition with the nasoseptal center, the medial part of the nasodorsal center.