CALCIUM Muthana A. Al-Shemeri

Dentistry Calcium In dentistry calcium is the chemical element that is needed for healthy teeth bones and nerves. Calcium chemical symbol Ca plays a very important role in building healthy teeth and bones as well as in our nervous system because it is required for normal communication between nerve cells. It controls muscles contract and hearts beat.

Calcium is the major mineral found in our bones and teeth and along with phosphorus and other nutrients calcium builds the hard structure that makes bones and teeth strong. We also need calcium for proper muscle and nerve function, blood clotting and other body processes. A high intake of dietary calcium in childhood is associated with healthy adult bones. Dentists and dieticians recommend that children get calcium through a balanced diet. A lack of calcium can lead to brittle fingernails, headaches, irritability, tooth decay and most importantly Osteoporosis

Osteoporosis Osteoporosis is a condition that causes bones to become brittle and can lead to increased risk of hip and vertebra fractures and spinal deformities leading to the loss of height. Osteoporosis occurs because the lack of calcium causes the body to take calcium from bone leading to the bones becoming weak.

CALCIUM Calcium metabolism or calcium homeostasis is the mechanism by which the body maintains adequate calcium levels. Derangements of this mechanism lead to hypercalcemia or hypocalcemia, which both can have important consequences for health.

Calcium location and quantity Calcium is the most abundant mineral in the human body. The average adult body contains in total approximately 1 kg, 99% in the skeleton in the form of calcium phosphate salts. The extracellular fluid (ECF) contains approximately 22.5 mmol, of which about 9 mmol is in the serum. Approximately 500 mmol of calcium is exchanged between bone and the ECF over a period of twenty-four hours

Normal ranges The serum level of calcium is closely regulated with a normal total calcium of (2.2-2.6 mmol/L) (9-10.5 mg/dL) and a normal ionized calcium of (1.1-1.4) mmol/L (4.5-5.6 mg/dL). The amount of total calcium varies with the level of serum albumin, a protein to which calcium is bound. The biologic effect of calcium is determined by the amount of ionized calcium, rather than the total calcium. Ionized calcium does not vary with the albumin level, and therefore it is useful to measure the ionized calcium level when the serum albumin is not within normal ranges.

Calcium Source There are many natural sources of calcium. Dairy foods such as milk, cheese and yogurt are the most abundant source of natural dietary calcium. Other good sources of calcium can be found in the various food groups summarized below: · Dairy: milk low-fat and fat-free yogurts low-.fat and fat-free cheeses · Meats/Beans: sardines/salmon with bones. · Fruits/Vegetables: orange juice · Grains: pancakes, breads and cereals · Combination Foods: cheese pizza (made with reduced-fat cheese) soups prepared with skim milk

The recommended daily intake of calcium It varies from children to adults; For children aged 1-3 the recommended amount of calcium is 500mg/day. This level increases to 800mg/day from ages 4-8 all the way up to 1300mg/day for teenagers. For adults is less than teenagers as the teeth and bones are almost fully formed at this stage of life and is around the 1000mg/day. Pregnant woman are advised to ingest 1100mg/day.

Calcium regulation Primarily calcium is regulated by the actions of 1,25-OH-vitamin D3, parathyroid hormone and calcitonin and direct exchange with the bone matrix. Plasma calcium levels are regulated by hormonal and non-hormonal mechanisms. After ingestion of substantial amounts of calcium, for example in a glass of milk, after about an hour, PTH will be released after about 8 hours. The PTH is, over time, a very potent regulator of plasma calcium, and controls the conversion of vitamin D into its active form in the kidney. The parathyroid glands are located behind the thyroid, and produce parathyroid hormone in response to low calcium levels. The parafollicular cells of the thyroid produce calcitonin in response to high calcium levels, but its significance is much smaller than that of PTH.

Pathology Hypocalcemia and hypercalcemia are both serious medical disorders. Renal osteodystrophy is a consequence of chronic renal failure related to the calcium metabolism. Osteoporosis and osteomalacia have been linked to calcium metabolism disorders.

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