ABSTRACT
Cell proliferation at the base of the enamel organ continues as the crown develops. The cervical loop (junction of the internal and external dental epithelium) becomes Hertwig’s epithelial root sheath. This structure determines root growth, shape, length, and form. Root formation begins after crown formation is completed. The root begins at the point where enamel formation terminates. Cells of the internal dental epithelium induce more papillary cells to differentiate into odontoblasts of the root. Cells of the outer root sheath differentiate into cementoblasts. These cells produce root cementum. Root elongation occurs as cells of the root sheath proliferate similarly to those that formed the crown.
