Current trends in mesenchymal stem cell application in bone augmentation: A review of the literature

Purpose: The literature regarding mesenchymal stem cell (MSC)-based bone reconstruction techniques are sparse and no comprehensive review of current methods has been performed. The aim of this article was to provide a discussion of clinical and experimental reports of MSC application in the reconstruction of bony defects in live models. Materials and Methods: This search was executed using the PubMed database with various combinations of related keywords. Currently published English-language studies that had applied MSCs as a part of their treatment protocol for reconstruction of bony defects in rat, rabbit, dog, and human models were reviewed. The included studies had reported substantiation that the applied cells were of MSC origin as a part of the study design. Publications inclusive to February 1, 2010 were evaluated. Of review of 187 found abstracts and full texts, 25 articles met the inclusion criteria. Result: Based on this review, tremendous differences exist among investigators for the application of MSCs in bone augmentation procedures. These differences include not only species uniqueness but also a plethora of other variances, such as stem cell source, defect sites and sizes, carriers and constructs, use of additional growth factors, measured parameters, and methods of data collection. Conclusion: Because of the multitude of protocols, range of parameters, and data in the current English-language literature, this review did not reach any significant conclusion as to the "most predictable" model in stem cell reconstruction. However, it does "shed light" on the need for additional collaborated studies using similar homogenous designs and data analysis in advancing the science of bone reconstruction using MSCs.