Introduction: The temporomandibular joint is susceptible to diseases andtrauma that may ultimately lead to structural degeneration. Currentapproaches for replacing degenerated mandibular condyles suffer fromdeficiencies such as donor site morbidity, immunorejection, implant wearand tear, and pathogen transmission. The emerging field of tissueengineering has widened the search for better and less invasive treatmentsfor many disease processes including those of the temporomandibular joint.Aim of the study: 1-In vitro engineering of bone and cartilaginous tissuefrom canine mesenchymal cells. 2-Assays for osteogenesis andchondrogenesis. 3-Radiographic, histological and immunohistchemicalassessment of tissue engineered bone and cartilage implant.Materials and methods: Canine bone marrow MSCs were aspirated from sixadult mongrel dogs, isolated and induced to differentiate into chondrogenicand osteogenic cells in vitro, seeded on a biocompatible silica calciumphosphate biphasic scaffold and implanted in-vivo at the site of inducedcondylar defect.Results: Sixteen weeks following in vivo implantation of the bilayeredosteochondral constructs , condylar osteocartilagenous tissue formed denovo. Microscopic and histochemical analysis of the tissue-engineeredosteochondral tissue demonstrated two stratified layers of histogenesis ofcartilaginous and osseous phenotypes. The current approach is being refinedfor ultimate therapeutic applications.