Magnetic resonance imaging assessment of bone regeneration in osseous defects filled with different biomaterials an experimental in vivo study

Abstract

Noninvasive techniques, such as Magnetic Resonance Imaging (MRI) are becoming more used in the study of bone regeneration outcomes, in both animal models and human patients. Many studies have shown the potential of tissue engineering therapies to promote healing of skeletal injuries, but further research is needed to optimize these treatment options. This investigation is a continuation of other previous published studies, in which critical-sized bone defects created in the parietal bones of Wistar rats were filled with either bioglass or a biologic collagen scaffold seeded both with adipose-derived mesenchymal stem cells. The present study aims to present the applications of MRI in the assessment of the bone regeneration process in these previously created defects, at specific time intervals. MRI techniques are based on the differences between the spin-latice T1 and spin-spin T2 relaxation times of examined specimens or areas, compared to normal tissues. We measured the relaxation times specific to calvarial specimens with a Brukner Minispec. The results showed that the most favorable results were observed when a collagen scaffold seeded with stem cells was used. MRI enabled the detection of hard and even soft tissue changes, these findings suggesting that MRI could be an effective imaging modality for assessing changes in bone morphology and pathobiology. Furthermore, it can be used as an alternative to Computed Tomography in examining the role of various biomaterials used in bone healing, especially when ionizing radiation is contraindicated.