Description of Research: Tissue engineering offers a viable alternative to bone grafts in repairing large bone defects. This involves using scaffolds of various sizes and shapes that contain stem cells and other osteoinductive molecules. Vitamin D3, a fat-soluble secosteroid that increases intestinal absorption of calcium, iron, magnesium, phosphate, and zinc, was tested to determine if it has an effect on adipose-derived stem cell (ASC) differentiation to osteoblasts.