Concise review: mesenchymal stromal cells used for periodontal regeneration: a systematic review

Abstract

Periodontitis is a chronic infectious disease of the soft and hard tissues supporting the teeth. Recent advances in regenerative medicine and stem cell biology have paved the way for periodontal tissue engineering. Mesenchymal stromal cells (MSCs) delivered in situ to periodontal defects may exert their effects at multiple levels, including neovascularization, immunomodulation, and tissue regeneration. This systematic review had two goals: (a) to objectively quantify key elements for efficacy and safety of MSCs used for periodontal regeneration and (b) to identify patterns in the existing literature to explain differences between studies and suggest recommendations for future research. This systematic review provided good evidence of the capacity of MSCs to regenerate periodontal tissues in animals; however, experimentally generated defects used in animal studies do not sufficiently mimic the pathophysiology of periodontitis in humans. Moreover, the safety of such interventions in humans still needs to be studied. There were marked differences between experimental and control groups that may be influenced by characteristics that are crucial to address before translation to human clinical trials. We suggest that the appropriate combination of cell source, carrier type, and biomolecules, as well as the inclusion of critical path issues for a given clinical case, should be further explored and refined before transitioning to clinical trials. Future studies should investigate periodontal regenerative procedures in animal models, including rodents, in which the defects generated are designed to more accurately reflect the inflammatory status of the host and the shift in their pathogenic microflora.

Keywords: Mesenchymal stromal cells; Periodontal diseases; Review; Stem cells; Systematic; Tissue engineering.

Figure 1.

Forest plot representing the 24 studies on alveolar bone regeneration by cell therapy. The result of each individual study with its confidence interval was plotted, and then a weighted average was calculated. The pooled analysis was given a diamond shape; the widest aspect of this shape is located at the global estimate and the corresponding horizontal width is the confidence interval. A random effect meta-analysis with the inverse variance method was used to obtain the global standardized mean difference with a 95% confidence interval. Bone regeneration was significantly higher in the cell therapy group than in the control group. Abbreviations: CI, confidence interval; df, degrees of freedom; IV, inverse variance; Std., standard.

Figure 2.

Forest plot representing the 17 studies on cementum regeneration by cell therapy. A random effect meta-analysis with the inverse variance method was used to obtain standardized mean difference with a 95% confidence interval. Cementum regeneration was significantly higher in the cell therapy group than in the control group. Abbreviations: CI, confidence interval; df, degrees of freedom; IV, inverse variance; Std., standard.