Signaling Networks Regulating Tooth Organogenesis and Regeneration, and the Specification of Dental Mesenchymal and Epithelial Cell Lineages

Abstract

SUMMARYTeeth develop as ectodermal appendages from epithelial and mesenchymal tissues. Tooth organogenesis is regulated by an intricate network of cell -cell signaling during all steps of development. The dental hard tissues, dentin, enamel, and cementum, are formed by unique cell types whose differentiation is intimately linked with morphogenesis. During evolution the capacity for tooth replacement has been reduced in mammals, whereas teeth have acquired more complex shapes. Mammalian teeth contain stem cells but they may not provide a source for bioengineering of human teeth. Therefore it is likely that nondental cells will have to be reprogrammed for the purpose of clinical tooth regeneration. Obviously this will require understanding of the mechanisms of normal development. The signaling networks mediating the epithelial-mesenchymal interactions during morphogenesis are well characterized but the molecular signatures of the odontogenic tissues remain to be uncovered. Outline

Integration of tooth morphogenesis and innervation by local tissue interactions, signaling networks, and semaphorin 3A

“…64,65 Studies of the functions and regulation of SEMA3A have unraveled novel developmental regulatory mechanisms regarding tooth innervation. The developing tooth germ controls its own innervation by local epithelial-mesenchymal tissue interactions, with the regulation of SEMA3A achieved via different conserved signaling effector families.…”

A Combined Epithelial Odontogenic Tumor? A 7-Year Follow-Up Case

“…Both AOT and CEOT cells are descended from epithelial odontogenic cell lineages and, if such neoplastic cells receive appropriate stimuli, they could perhaps give rise to similar ''reprogrammed'' neoplastic daughter cells in either lesion or even any odontogenic tumor of epithelial origin for that matter, as previously shown in other cells and tissues [27][28][29]. Such an assumption requires further investigation, as the inductive potential of the neoplastic epithelial odontogenic cell lines has not been explored [29].…”

Natural odontogenesis: cellular and molecular basis

“…Человек имеет зубы всех типов, а мыши толь-ко резцы и моляры (рис. 1) [8]. Люди имеют два по-коления зубов: временные или «молочные» и посто-янные.…”

“…Адаптирован с рисунка из Jussila and Thesleff, 2012. фундаментальные исследования дает способностью к регенерации. Это связано с тем, что в ответ на механические повреждения одон-тобласты или мезенхимальные клетки пульпы зуба могут дополнительно откладывать дентин [10].…”

“…Процесс развития зуба делят на стадии плакоды, почки, колпачка, колокола и развития корня (рис. 3) [8]. Наиболее детально эти стадии из-учены на экспериментальных мышах.…”