Int. J. Dev. Biol. 37: 581 - 588 (1993)

Vol 37, Issue 4

Multiple developmental origin of the upper incisor in mouse: histological and computer assisted 3-D-reconstruction studies

Published: 1 December 1993

R Peterková, M Peterka, J L Vonesch and J V Ruch

Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague.

Abstract

Heads of 11-15-day-old mouse embryos were cut in frontal serial sections. Early development of the maxillary incisor was analyzed using series of thick (5 and 7 microns) and semi-thin (1 micron) frontal sections and computer assisted 3-D-reconstructions of the epithelial component. The enamel organ of the mouse maxillary incisor was found to be a complex structure of multiple origin, involving several epithelial anlagen--primary dental laminae--, which could hypothetically correspond to the 5 upper incisors of early mammals. The transitory existence of at once distinct and then fusing dental primordia could reflect heterochronic changes in ontogeny which might be related to phyletic trends.