OBJECTIVETo compare the attachment and growth characteristics between human junctional epithelium (JE) and oral epithelium cells.

METHODSThe healthy JE biopsies were derived from the human teeth extracted due to impaction or orthodontic purpose. Enzyme digestion was used to isolate JE cells, which were then cultured in DKGM. The co-culture model of JE cell-tooth slice was built up by adding 3 decalcification cementum slices (5 mm x 3 mm x 1 mm) into sterilized plate containing 1 ml of JE cells (5 x 10(8)/L), 21 slices all together,and incubated in an atmosphere containing 5% CO2 at 37 degrees C for 1-14 days. The attachment structure was observed under transmission electron microscope, and the OE cells was used as control.

RESULTSThe human JE cells were polymorphous in shape and CK19 positive, while OE cells were consisted of equal and closely packed epithelial-like cells in a paving stone arrangement, and CK19 was only strained in a few cells. There were a few cells in JE-slice when co-cultured for 1-3 days, and electron dense plaques on the JE cell surface of the attached slice were observed at 9 days, and 2-3 layer of JE cells and hemidesmosome-like structure formed within 11-14 days. There were more OE cells within 1-3 days, electron dense plaques appeared at 7 days, and stratified epithelium and hemidesmosome-like structure formed in OE-slice at 9 days.

CONCLUSIONSThe cultured JE cells were immature and lower differentiated epithelial cells which were different from OE cells. Under the same condition the growth and attachment of JE cells on the cementum slice surface were slower than that of OE cells. Their attachment strength needs further study.