lGrowth of the root pushing against the
alveolar bone forces the crown through the gums.
lContradictions:
lRootless teeth erupt
lEruptive movements of teeth do not coincide
with the total length of their roots
lEruption occurs even after root
completion
lEruption occurs even after surgical removal
of Hertwig's epithelial root sheath, periapical tissue and apical papilla
lImpacted and unerupted permanent teeth with completely formed roots erupt after surgical
exposure