Enamel matrix derivative (EMD) secreted by cells of the epithelial root she
ath plays an important role in cementogenesis and periodontal tissue format
ion. The mechanisms by which EMD influences cell function are not known. Th
e purpose of this study was to determine the effect of EMD on cell growth o
f primary mouse osteoblasts, Osteoblasts were digested from 6- to 8-day-old
mouse calvaria and plated into 6-well cell culture plates at an initial de
nsity of 5000 cells/cm(2). After 24-h incubation with Dulbecco's modified e
agle medium (DMEM) supplemented with 10% fetal bovine serum, cells were inc
ubated in three different groups of media: DMEM only as control, DMEM with
25 mug/ml EMD, and DMEM with 100 mug/ml EMD, At days 3, 7, 10, and 14, the
total cell number per well was calculated, and cell morphology was examined
. At each observation period the number of cells in the EMD groups was sign
ificantly greater (ANOVA, p < 0.01) than that in the control group. EMD had
a greater effect on osteoblast survivor in the higher concentration than i
n the lower concentration, Furthermore normal morphology of the primary ost
eoblasts was maintained in the EMD groups, These results suggest that EMD p
rolongs primary osteoblast growth and may have an effect on osteoblasts dur
ing periodontal regeneration.