Miracle of Facial Development: A Journey in Embryology -

Facial morphogenesis in the fetus occurs between the 5th and 10th week when five mesenchymal swellings fuse: the frontonasal prominence, two mandibular processes, and two maxillary processes. Failure to grow and fuse these prominences can cause facial deformities, some of which I will discuss in separate video. The first pharyngeal arch produces the maxillary and mandibular processes, which is why the trigeminal nerve supplies facial sensibility. Neural crest mesenchyme forms frontonasal prominence. Nasal placodes-ring-like bilateral thickening on the frontonasal prominence-develop in the fifth week. Placode edge enlarges, while center pits produce nasal pits. Lateral and medial nasal prominences develop from the placode's lateral and medial edges. Over two weeks, maxillary processes expand medially to the lateral nasal prominence and unite. The deep groove between the maxillary processes and lateral nasal prominence deepens into the nasolacrimal duct. This growth presses the medial nasal prominences towards the mid-line until they combine to form the nose's center and lip philtrum. Mid-line mandibular processes merge. Please watch the video for further details.