טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentSemel Gabriel
SubjectEndochondral Ossification of Mandibular Condyle - the
Impact of Shock Wave Therapy
DepartmentDepartment of Medicine
Supervisors Clinical Professor Dror Aizenbud
Dr. Gila Maor


Abstract

In the current study we focused on the effects of extra corporal shock wave treatment )ESWT ( on endochondral ossification (EO).We explored the effects of one single pulse of shock waves, applied at the beginning of culture period, on the expression of structural and regulatory cartilage-specific genes. We hypothesized that the application of ESWT on mandibular condyle might affect the endochondral growth rate and mediate its activities through modulation of local regulatory factors. 

A mandibular condyle derived chondrocytes (MCDC)-primary chondrocyte culture served as a model for ex-vivo endochondral ossification (EO). MCDC cultures follow a normal cascade of proliferation differentiation and maturation of endochondral

ossification. The culture may be split twice without losing its chondrogenic characteristics. The MCDC cells were cultured in chamber slides for 3, 5 and 8 days. The cultures were exposed to a single application of 500 unfocused impulses of ESWT at an energy flux density of 0.05mj/mm2 24 hours post culture.

The results show that ESWT exerts positive stimulation effects on proliferating activities of chondrocytes thus contributing to the growth potential of the MCDC cultures. However, the findings of our study do not indicate further up regulating effects on chondrocytes differentiation and maturation. Our results show that the PTHrP/Ihh axis slightly up-regulated and VEGF significantly increased during the first chondrogenesis phase - two days after application of shock waves. In contrast, continuous treatment with VEGF induced both proliferation and differentiation of chondrocyte cells.




Based on these results we can conclude that a single episode of shock wave treatment has a positive impact on chondrogenesis in our experimental model. Hence, perhaps prolonged EWST activity might induce an impact on the entire chondrogenesis cascade, as exemplified by the constant treatment of VEGF to induce an impact on both proliferation and differentiation of chondrocyte cells. Preliminary results show that constant VEGF-treated cultures exhibit accelerated chondrogenesis including proliferation and major differentiation parameters. We assume that under proper shock wave conditions that allow constant impact of physical forces, the increased VEGF levels present throughout the culture period might induce significant up-regulation of chondrogenesis.