Study on the differences of reconstructive periodontium by stem cell sheets and normal periodontium under the orthodontic force

To discuss the feasibility of orthodontic treatment for regenerated periodontal tissues by comparing the difference of tooth movement under orthodontic forces between the normal periodontal tissues and the reconstructed periodontal tissues by the composite cell sheets of dental follicle cells (DFCs) and periodontal ligament stem cells (PDLSCs).

Six adult male beagles were selected for experiment animals. The first premolar in all four quadrants of each beagle were extracted and a bone defect were made in the same size (4 mm × 4 mm × 4 mm) distal to the extraction sockets. The upper left and the lower right quadrants were divided into the regeneration group by transplantation of the composite cell sheets while the upper right and lower left quadrants were control group without transplantation. 12 weeks after transplantation, the orthodontic forces were introduced to move the second premolar mesially with a force value 150 g. Measurements were done after 4 weeks of traction to record the movement of the tooth. And compare the difference between the regeneration group and control group by the statistical analysis.

DFCs/PDLSCs composite cell sheets repaired the periodontaltissue and formed the typical alveolar bone-periodontal membrane-cementum structurewhich shows good histological characteristics. experimental group and control group show no statistical difference in the rate of tooth movement (P＞0.05).

The periodontal tissues regenerated by this kind of the composite cell sheet showed a good response to mechanical stimulation.