Serum-containing medium effect on isolation rate of dental pulp cells from cryopreserved intact deciduous teeth

To isolate cells from pulp of intact cryopreserved deciduous teeth. The null hypothesis raised here is to find no difference in the establishment of cell culture after cryopreservation (1) using culture medium supplemented with different concentrations of fetal bovine serum (FBS); and (2) between teeth with different stages of physiological root resorption.

Intact deciduous teeth with different root resorption stages were cryopreserved using FBS and Dimethyl Sulfoxide (DMSO) medium (9:1) in a progressive freezing process, by placing the samples in the refrigerator (4 degrees C/60 min) and subsequently transferring them to a -80 degrees C freezer (controlled device -1 degrees C/min/24 hours), and finally into liquid nitrogen (-196 degrees C/30 days). After the thawing process, the cell isolation was performed by enzymatic digestion (type I collagenase). The cells were re-suspended into the culture medium with 10% (G1) or 20% (G2) of FBS. Microscopic analysis was performed after 30 days to visualize the cell attachment.

The culture establishment rate was higher in G2 (75%) than G1 (12.5%) (p = 0.041). There was no difference between the different stages of root resorption.

It was possible to establish cell cultures from the pulp of intact cryopreserved deciduous teeth. The use of 20% FBS after thawing improved the culture rate.