Overview about calcium
Effects of minerals on calcium
Dietary sources of calcium
Daily requirement of calcium
Function & Storage
Distribution of calcium
Absorption of calcium
Regulation of calcium
Disorders of calcium metabolism
3. OVERVIEW ABOUT CALCIUM
About 99% of calcium in our body is found in BONES.
The concentration of calcium in plasma is higher than the interstitial fluid.
Intracellular concentration of calcium is considerably less that is 1%.
Most abundant mineral in the human body.
Total calcium in the human body is about 1 to 1.5 kg.
4. EFFECTS OF MINERALS ON CALCIUM
Phosphate : decreases the calcium excretion in the urine.
Caffeine : increases the calcium excretion in urine and feces.
Sodium : increased sodium intake also increases calcium in urine.
Iron : calcium might have inhibitory effect on iron absorption.
5. DIETARY SOURCES OF CALCIUM
Milk is a good source of calcium.
Egg, fish, cheese, beans, lentils, nuts, cabbage and vegetables.
6. DIETARY SOURCES
Whole milk = 10%
Low fat milk = 18%
Cheese = 27%
Other dairy products = 17%
Vegetables = 7%
Other substances such as meat, egg, grains, sugar, coffee, tea, chocolate, etc. = 21%
7. DAILY REQUIREMENT OF CALCIUM
Adults = 500mg/day
Children = 1200mg/day
NOTE- After the age of 50, tendency for osteoporosis is increased so that it is
prevented by increased calcium (1500mg/day) & vitamin D (20ɥg/day)
9. FUNCTION OF CALCIUM
Calcium is very essential for many activities
in the body such as:
Bone & teeth
10. STORAGE OF CALCIUM
Primary site for storage of calcium is bones(about 1000 gms)
Some calcium is stored within cells(endoplasmic reticulum and mitochondria)
Bone is produced by osteoblast cells which produce collagen, which is then
metabolized by calcium and phosphate into the blood stream.
There is constant exchange of calcium between blood and bone.
11. • calcium in plasma is of 3 types – FREE or BOUND or
• In blood, 50% of calcium is free & is metabolically active.
• It is required for the maintenance of nerve function,
membrane permeability, muscle contraction and hormone
• Bound calcium : 41% of plasma calcium is bound to
protein mostly albumin.
• Complexed calcium : 9% of plasma calcium is complexed
with anions including bicarbonate, phosphate, lactate and
13. MECHANISM OF ABSORPTION OF
Calcium is taken in the diet as calcium phosphate, carbonate, tartrate.
About 40% of dietary calcium is absorbed from the gut.
Absorption occurs in the first and second part of duodenum.
Requires a carrier protein and helped by calcium-dependent ATPase.
400mg is excreted through stools and 100mg is excreted through urine
17. CALCIUM REGULATION
By 3 main organs :
By 3 main hormones :
1) Parathyroid hormone (PTH)
2) Vitamin D ( calcitriol )
19. ROLE OF PTH ON CALCIUM REGULATION
PTH is secreted by two pairs of parathyroid glands.
Parathyroid hormone is a single chain polypeptide containing 84 amino acids.
It is initially synthesized as PreProPTH which is degraded as ProPTH and finally to
The rate of formation & secretion of PTH are promoted by low Ca++ concentration.
21. ROLE OF CALCITRIOL ON CALCIUM
On Bone – stimulates calcium uptake for deposition of calcium phosphate.
On Intestine – increases intestinal absorption of Ca2+ and phosphate.
On Kidneys – minimizing the excretion of Ca2+ and phosphate and hence enhancing
22. ROLE OF CALCITONIN ON CALCIUM
Calcitonin is a peptide containing 32 amino acids.
It is secreted by parafollicular cells of thyroid gland.
The action of Calcitonin on calcium regulation is just antagonistic to PTH.
Calcitonin promotes calcification of bone.
Calcitonin decreases the bone resorption and hence increases the calcium excretion.
It has a decreased influence on blood calcium.
23. EXCRETION OF CALCIUM
The major site for calcium excretion is by kidneys.
The rate of calcium loss and reabsorption at the kidney can be regulated.
Regulation of absorption, storage and excretion of calcium results in maintenance of
24. • About 1,000 mg of calcium is excreted
daily. Out of this, 900 mg is excreted through
faeces and 100 mg through urine.
• Most of the filtered calcium is reabsorbed in
the proximal convoluted tubules and proximal
part of collecting duct.
• In distal convoluted tubule, PTH increases the
• In collecting duct, vitamin D increases the
reabsorption and calcitonin decreases
• Calcitonin (Miacalcin) - This hormone from salmon controls calcium
levels in the blood.
• Calcimimetics - This type of drug can help control overactive
parathyroid glands. Cinacalcet (Sensipar) has been approved for
• Denosumab (Prolia, Xgeva) - This drug is often used to treat people
with cancer-caused hypercalcemia who don't respond well to
29. • Steroid (Prednisone) - If your hypercalcemia is caused by high levels of
• IV Saline & furosemide for rapid correction - In case of emergency.
• Bisphosphonates - Intravenous osteoporosis drugs, which can quickly
lower calcium levels, are often used to treat hypercalcemia due to cancer.
37. Giant Cell Granuloma
Loss of lamina dura,
pathognomonic oral change
Panoramic image shows the loss of bone. The
radiopaque teeth standing out in contrast to the
38. •Oral calcium supplements — as tablets, chews or liquid — can increase calcium
levels in your blood.
•High doses of vitamin D, generally in the form of calcitriol, can help your body
absorb calcium and eliminate phosphorus.
•Parathyroid hormone replacement
There are different types of hypoparathyroidism, including acquired, autoimmune, congenital, and
•Acquired: This is the most common type. It occurs after removal of or damage to the parathyroid glands,
either through surgery or an injury.
•Autoimmune: This is the second most common type of hypoparathyroidism and occurs because
the immune system mistakenly attacks the parathyroid gland or the parathyroid hormone.
•Congenital: This is a much rarer type of hypoparathyroidism that appears at birth. It is the result of gene
mutations in the parathyroid hormone process, or someone being born without parathyroid glands.
•Familial: If you have a family history of hypoparathyroidism, you have a higher risk of developing familial
40. Signs and symptoms:
•Tingling and burning in your fingertips, toes and lips
•Fatigue and weakness
•Painful menstrual periods
•Patchy hair loss
•Dry, coarse skin
•Depression or anxiety
•Muscle aches or cramps in your legs, feet, face or
•Spasm on your muscle
41. Currently, the standard treatment for
hypoparathyroidism consists of activated vitamin D
(calcitriol) and calcium supplements. Some people
may also need magnesium supplementation.
• Disturbances in calcium excretion and transcellular shift result in deranged metabolism
accounting for abnormal serum levels. An understanding of calcium is required for the
clinician to evaluate disorders of the levels of calcium as well as metabolic & skeletal
disorders. Therefore, the dental observation of disturbances in tooth formation and
eruption pattern may be of crucial importance for the clinician.
Essential of medical physiology sembulingam ,5/e
Davidson’s principles and practice of medicine, 19/e.
Harrison principle of internal medicine,18/e.
Shafer’s textbook of oral pathology ,7/e.
Textbook of biochemistry by u. Satyanarayana, 2/E
Burkett's oral medicine 11th edition
Calcium and Phosphate Metabolism – Annual Review of Physiology Vol. 36: 361-390 A B Borle
Oral manifestations of parathyroid disorders and its dental management, journal of dental and allied sci year : 2014
| volume : 3 | issue : 1
J of applied oral sc. 2013 nov-dec; 21(6): 601–606