Evaluation of preserving the viability of sheep's teeth PDL cells according to the different times and storage medias

 Vitality of periodontal ligament (PDL) cells is very critical for replantation of complete avulsion teeth due to traumatic injuries. This is important for transferring an avulsed tooth to clinic for replantation that which Medias used for storage.This study aimed to compare the vitality of PDL cells of sheep teeth cultured in different storage medias including α-Minimum Essential Medium (αMEM), Dulbecco’s Modified Eagle’s Medium (DMEM), Hank’s Balanced Salt Solution (HBSS), and mint extract In this lab trial study, PDL cells were obtained from 124 healthy anterior and posterior sheep teeth and cultured in αMEM, DMEM, HBSS, and mint extract for periods of  2, 6, 24, 48, 72, or 96 hours (24 groups). For each solution, positive control group were PDL cells without incubation in any storage media. For each group, there was a negative control considered cells growing in dry plate with no medium. After exposure of PDL cells to scheduled solution for scheduled incubation time, centrifuge was performed for 10 minutes at rate of 2000G. Then cell percipitates were added into the solution of collagenase (3mgr/ml) and Dispase (4mgr/ml to cell precipitates, which were incubated at 37° C for 60 minutes. After washing cellular suspension in PBS, vitality of the cells was assessed by Trypan blue exclusion, on a neobar slide by magnification of 200X. The data were analyzed statistically using 2-way ANOVA test by SPSS version 15. Statistically significant differences in efficacy of different medias were obtained at least between two media (P=0.0001). PDL cells cultured in αMEM and mint extract showed 90% and 52.22% vitality representing, respectively, the best and the weakest storage media. αMEM can be a suitable transport medium up to 96 hours to preserve the vitality of the PDL cells of avulsed teeth. There is a reverse correlation between the viability of PDL cells and incubation time, increasing the time decreases the viability.