Are Stem Cells Useful in the Regeneration and Repair of Cartilage Defects in the TMJ Condyle? An In Vivo Study

Temporomandibular Joint (TMJ) disorders affect up to 10-40% of the population and if left untreated, may eventually lead to Osteoarthritis (OA) of the TMJ. In vivo TMJ repair and regeneration has received significant attention and represents a promising approach for the treatment of degenerative TMJ disorders. The aim of this study was to present a pre-clinical mouse model of TMJ articular cartilage defect and evaluate the utility of a potential tissue engineered TMJ therapy utilizing Mesenchymal Stem Cells (MSCs) derived from mice condyle, hydrogel, and biosilica. C57BL/6 mice (n=30) were equally divided into the following groups: sham group (S-group); control group, condylar cartilage defect only (CD-group); experimental group, condylar cartilage defect + direct administration of MSCs+hydrogel+biosilica (H-group). Mice were euthanized at 4 (n=15) and 8 (n=15) weeks and TMJ joint specimens were harvested for analysis. H&E and Safranin O stained sections showed intact articular surfaces on the condyle and glenoid fossa at both time points, maturation and distribution of chondrocytes along the condyle for the H-group compared to the CD-group. Data from this preliminary study shows that MSCs+hydrogel+biosilica may represent an experimental therapeutic compound for TMJ condylar cartilage regeneration.