Systematic Review of Human Dental Pulp Stem Cells for Cartilage Regeneration

Background: Symptomatic cartilage lesions and early osteoarthritis produce significant clinical and economic burdens. Cartilage repair can improve the symptoms and delay arthroplasty. The complete healing of damaged cartilage with the consistent reproduction of normal hyaline cartilage has not yet been achieved. The choice of harvesting site might influence the cells' abilities to modulate immunologic and inflammatory responses. Recently, dental pulp has been shown to contain a stem cell niche consisting of dental pulp stem cells (DPSCs) that maintain their self-renewal capacity due to the active environment in the dental pulp of deciduous teeth. Objective: The aim of this study was to critically review the current literature on the potential and limitations of the use of dental pulp-derived mesenchymal stem cells in cell-based therapies for cartilage regeneration. Methods: An electronic, customized search of scientific articles was conducted using the PubMed/MEDLINE and EMBASE databases from their inception to December 2018. The inclusion criteria were applied, and the articles that described the use of DPSC in cartilage treatment were selected for complete evaluation. The articles were classified according to the scaffold used, experimental model, chondrogenic differentiation features, defect location, cartilage evaluation, and results. After the application of the eligibility criteria, a total of nine studies were selected and fully analyzed. Results: A variety of animal models were used, including mice, rats, rabbits, and miniature pigs, to evaluate the quality and safety of human DPSCs in the repair of cartilage defects. Among the articles, two studies focused on preclinical models of cartilage tissue engineering. Five studies implanted DPSCs in other animal sites. Conclusion: The use of DPSCs is a potential new stem cell therapy for articular cartilage repair. The preclinical evidence discussed in this article provides a solid foundation for future clinical trials. Impact statement Osteoarthritis presents an ever-increasing clinical and socioeconomic burden. While cartilage repair has the potential to improve symptoms and delay joint replacement, complete regeneration of hyaline cartilage has been an elusive goal. Dental pulp has been shown to contain a niche that protects dental pulp stem cells (DPSCs) from the cumulative effects of genetic and environmental factors and maintains their self-renewal capacity due to the active environment. Transplantation and preclinical trials have demonstrated the strong potential of regenerative tissue-engineering protocols using DPSCs.