ABSTRACT
Statement of the Problem: A great challenge in periodontal therapy is the regeneration enhancement of osseous defects through applying osteoinductive materials. Demineralized freeze-dried bone allograft [DFDBA] has already been introduced as an allograft with osteoconductive and variable osteoinductive properties. Calcium hydroxide [Ca[OH]2] is an available well-known material in dentistry, which induces hard tissue formation
Purpose: This study evaluated the efficiency of combination of DFDBA and Ca[OH]2 in improving the quality of osteoinduction of DFDBA
Materials and Method: Human bone marrow-derived mesenchymal stem cells were taken from volunteers' iliac crest. Cell proliferation was determined by MTT test at 18, 24 and 48 hours post-culture in 10 groups. The employed material were 0.5, 1.0 mg/ml Ca[OH]2 in two forms of suspension and pH-adjusted solution, 10mg/ml DFDBA per se and in combination with 0.5 and 1.0 mg/ml Ca[OH]2. Mineralization was assessed by Alizarin red staining in 10 mg/ml DFDBA, DFDBA+ 0.5 and 1 mg/ml Ca[OH]2 in solution and suspension forms. The data were statistically analyzed by using one-way ANOVA and Tukey's post-hoc test [p< 0.05]
Results: The pH-adjusted solutions exhibited better cell proliferation compared with the suspension groups. The combination of 0.5mg/ml Ca[OH]2 solution and DFDBA increased the cell proliferation and mineralization compared with DFDBA per se [p= 0.033]
Conclusion: The combination of Ca[OH]2 with DFDBA improved the osteoinductivity of DFDBA
ABSTRACT
The treatment of diabetes mellitus, as a chronic and complicated disease, is a valuable purpose. Islet transplantation can provide metabolic stability and insulin independence in type 1 diabetes patients. Diet and insulin therapy are only diabetes controllers and cannot remove all of the diabetes complications. Moreover, islet transplantation is more promising treatment than whole pancreas transplantation because of lesser invasive surgical procedure and morbidity and mortality. According to the importance of extracellular matrix for islet viability and function, microenvironment remodeling of pancreatic endocrine tissue can lead to more success in diabetes treatment by pancreatic islets. Production of bioengineered pancreas and remodeling of pancreas extracellular matrix provide essential microenvironment for re-vascularization, re-innervation and signaling cascades triggering. Therefore, islets show better viability and function in these conditions. Researchers conduct various scaffolds with different biomaterials for the improvement of islet viability, function and transplantation outcome. The attention to normal pancreas anatomy, embryology and histology is critical to understand the pancreatic Langerhans islets niche and finally to achieve efficient engineered structure. Therefore, in the present study, the status and components of the islets niche is mentioned and fundamental issues related to the tissue engineering of this structure is considered. The purpose of this review article is summarization of recent progress in the endocrine pancreas tissue engineering and biomaterials and biological aspects of it.