Both these matrices are elaborated by osteoblasts and osteocytes . Osteoblasts begin the elaboration, and when osteoblasts become surrounded by what they've elaborated, the become known as osteocytes. Osteocytes secrete much less collagen than do osteoblasts. Osteocytes are the permanent living cells of the bone matrix. The final cell in bone is the osteoclast .
Osteoclasts are what remodel bone.
They are stimulated by Vitamin D on the surfaces of osteocytes. The image to the left is a typical cross-section of bone stained with the standard hematoxylin and eosin stain. The dark pink web-link branching throughout the image you see on the left is decalcified bone. Punctuated along the decalcified bone are the osteoblasts. The presence of blood vessels in bone implies that bone is indeed a living tissue and that the cells require nutrients, especially oxygen.