Regeneration of periodontal tissues using allogeneic periodontal ligament stem cells in an ovine model

Aim: To investigate the capacity of allogeneic periodontal ligament stem cells (PDLSCs) to regenerate periodontal tissues using an ovine periodontal defect model. Materials & methods: Surgically created zero-wall dehiscence periodontal defects created in Merino sheep were filled with 1 × 10 ⁷ allogeneic PDLSCs attached to Gelfoam^®, Gelfoam alone or left untreated. After 4 weeks, histological analysis was performed to assess periodontal regeneration. Results: Allogeneic PDLSCs were well tolerated by recipient animals. The mean area of new alveolar bone was significantly greater in the PDLSC + Gelfoam treatment group compared with the defect-alone group. The PDLSC + Gelfoam and Gelfoam-only treatment groups displayed significantly greater length of new cementum and percentage of cementum regrowth compared with the defect-alone group. New Sharpey's fibers were generally more organized and significantly thicker within the PDLSC + Gelfoam treatment group. The PDLSC + Gelfoam treatment group also showed a trend of increased Sharpey's fiber attachment length compared with the Gelfoam-only and defect-alone groups. Conclusion: These studies support the potential use of allogeneic PDLSC preparations as viable therapies for periodontal regeneration in the clinical setting.