Bone is a specialized mineralized connective tissue made up of an organic matrix of collagen fibrils embedded in an amorphous substance with mineral crystals precipitated within the matrix. It is highly vascular, living, constantly changing mineralized connective tissue with complicated hierarchical architecture. The human skeleton is bilaterally symmetrical with the typical vertebrate pattern of an axis, divided into segments for flexibility, and of two pairs of limbs, pectoral and pelvic for locomotion, grasping etc. Teeth is hardest and most stable of tissues. They are the excellent models of studying the relations between ontogeny and progeny. Bone health is critically important to the overall health and quality of life of an individual. Bones serve as a storehouse for minerals that are vital to the functioning of many other life-sustaining systems in the body. Both genes and the environment contribute to bone health. External factors, such as diet and physical activity, are critically important to bone health throughout life and can be modified. Thus bones have fascinated human beings since the dawn of time. Remarkable progress has been gained in our understanding of the cellu