The body contains more calcium than any other mineral. Calcium and phosphorus account for 75% of total mineral element in the body. The new born infant has about 28gm of calcium as a store. Ninety-nine per cent of the total calcium in the body is concentrated in the bones and teeth; the remainder is in the fluids and soft tissues.
Calcium serves two important functions in the body the building of bones and teeth and regulating certain body processes. The need for calcium in the building of the skeleton is of course, grater during the year of. However the need doesn’t end when full growth is attained. Once the bone is formed, it continues to change with the processes of building new bone and maintaining the old. The normal behavior of heart muscles, nerves and the blood clotting processes all depend on the presence of calcium.
Building Bones and Teeth
Calcium and phosphorus are mainly present in bones and teeth. Calcium together with other mineral elements gives rigidity and permanence to bones and teeth. These characteristics make it possible for the bone to be support of the body, providing the rigid structure two which the muscle tissue is attached. Bones forms protective cavities for vital organs–the heart and lungs in the chest cavity, the brain in the cranial cavity. Bone will with stand almost as much weight as cast iron before breaking. It is itself light in weight.
The calcium absorbed combines with phosphorus and water to form calcium phosphate. First fibrous network made up of collagen and other nitrogenous substances is formed. Then the bone minerals are deposited on this network as crystals. These crystals are redissolved and recrystallised to form bone tissue. During recrystallization some of the water is lost and the structure of crystals is also changed to form bone.
A number of factors influence the mineralization and resorption of bone. Amount of vitamin D at the bone site are essential for the deposit of minerals in to the matrix. On the other hand the activities of the parathyroid gland bring about resorption of bone. The emotions have an important bearing up on the calcium balance.
Teeth like the bones contain both organic and organic matters with the inorganic portion comprising the major part. Enamel, the outermost covering is approximately 99.5% inorganic matter; dentine the portion beneath the enamel and surrounding the tooth pulp is about 77% and cementum, the classified portion covering the root of the tooth is approximately 70% inorganic matter.
Enamel, the hardest tissue in the body, contains 36% calcium and 17%phosphurus, which are more of minerals than is contained in any other tissue. Dentine is 27% calcium and 13% phosphorus. Some exchange of minerals between enamels and saliva occurs. While bone has the capacity to repair itself after a portion has been injured mechanically or through decay, the enamel is not able to do this.