Growth and migration of gingival epithelial cells on mineralized and partially demineralized root surfaces in an in vitro system.

The capacity of epithelial cells to migrate and grow from gingival explants cultured on mineralized and partially demineralized root surfaces in an in vitro system was assessed. Explants of attached gingiva were obtained from mongrel dogs, cut into rectangular pieces (1 x 2 mm) and cultured either on mineralized or partially demineralized cementum in a defined culture medium containing transferrin, insulin, epidermal growth factor, cortisone, high density lipoprotein and selenium. After seven days of culture, the specimens were prepared for scanning electron microscopic examination. The amount of epithelial outgrowth from each explant was assessed by measuring the distances between the four aspects of the rectangular explant and the furthest epithelial cell located opposite to each of these aspects. The mean value obtained for epithelial outgrowth of explants grown on mineralized cementum was six times higher than that for explants cultured on partially demineralized cementum. These results indicate that partially demineralized cementum does not support epithelial growth and migration in vitro.