Development of Head, Neck, and Oral Cavity John R. Fredieu PhD x6012 jrf6@case

1. Development of Head, Neck, and Oral Cavity John R. Fredieu PhD x6012 jrf6@case.edu

2. Images were obtained from: Congenital Anomalies of the Ear, Nose, and Throat. Tewfik, TL and Der Kaloustian, VM, eds., Oxford University Press, 1997 Human Biology and Developmental Biology. Carlson, BM, Elsevier Inc. 3rd Edition. Oral Development and Histology. Avery JK, Steele PF, and Avery, N, eds., Thieme Medical Publishers, 2002.

3. The amazing thing about . . . development is not that it sometimes goes wrong, but that it ever succeeds. - Veronica van Heyningen (2000) Why is embryology applicable to head and neck anatomy? Understanding tissue development helps to define tissue structure and relationships, and enriches the learning of anatomy. Embryology helps the student understand specific cranial nerve distributions and innervations. Embryology explains many congenital abnormalities seen in a population

10. Gagan et al, 2007

16. Arch 1

20. columella nasi prochilon nasal fin

23. Opposing epithelial layers fuse. Epithelial seam eventually disappears - due to apoptosis - due to epithelial to mesenchymal transition - due to migration away from the region

25. Ectoderm induces aggregation of ectomesenchyme initially, then loses ability to induce aggregation. Ectomesenchyme, after aggregation, can induce tooth formation in other ectoderm by inducing the formation of an enamel knot.

26. Arch 2

33. (copula)

38. Farlie et al 2004