A minimally invasive transfer method of mesenchymal stem cells to the intact periodontal ligament of rat teeth: a preliminary study

The aim of this study was to introduce a minimally invasive procedure for mesenchymal stem cell (MSC) transfer into the intact periodontal ligament (PDL) of the molar teeth in rats. Ten 12-week-old Wistar albino rats were used for this preliminary study. MSCs were obtained from bones of two animals and were labeled with green fluorescent protein (GFP). Four animals were randomly selected for MSC injection, while 4 animals served as a control group. Samples were prepared for histological analysis, Cox-2 mRNA expression polymerase chain reaction analysis, and fluorescent microscopy evaluation. The number of total cells, number of osteoclastic cells, and Cox-2 mRNA expression levels of the periodontal tissue of teeth were calculated. The number of total cells was increased with MSC injections in PDL significantly (P < 0.001). The number of osteoclastic cells and Cox-2 mRNA expression were found to be similar for the two groups. GFP-labeled MSCs were observed with an expected luminescence on the smear samples of the PDL with transferred MSCs. The results of this preliminary study demonstrate successful evidence of transferring MSCs to intact PDL in a nonsurgical way and offer a minimally invasive procedure for transfer of MSCs to periodontal tissues.