Saturday, 26 July 2014

VITAMINS – THE MICRONUTRIENTS

CHAPTER NO. 11
VITAMINS – THE MICRONUTRIENTS
            The body of the animals grows by eating different foods e.g meat, Bread, vegetables, fats etc. they all help to build the body of animals and maintain it. They are termed as “nutrients” . In Addition to these basic nutrient e.g . fats, proteins or carbohydrates, there are certain other things, special chemicals which are eaten by  the  animal-termed as “micro-nutrients”. They are termed so because they are required in very small quantities but are very important for “the life “. They make a part of certain molecules or they may be necessary for some reactions to take place or we can say that some of the reactions cannot take place without these chemicals substances. That is the reason why the micro-nutrients are important to life.
             Vitamins are important micro-nutrients. They help in the maintenance and propagation of life and the wellbeing of a person. They have got their effect on the body in general and some special findings may be observed in the oral tissues, by deficiency or excess of them. Following pages small help explore the signs and symptoms in and  around the oral cavity both in excess or deficiency of  different vitamins.
VITAMIN-A RTINOL
            It is only found In animals kingdom. I n plants only its precursors e.g B-carotene,   may be found. It is an alcohol and is absorbed in body through as fats in the form of chylomicron and is stored in liver which may be maintain the blood level for year.
            In blood, it is bound to a “RBP” (retinal building protein) and for its mobilization, Zn is necessary. A pseudo deficiency may be seen in liver disease. Zn deficiency and in protein deficiency.
ACTIONS:
            It has an important role in maintenance of the epithelial surfaces. It helps produce glycoproteins which are integral part of cell membrane. Deficiency shows in form of changes in glands, eye and mucous surfaces as well as other signs.
            It plays an important role in color vision and vision in dim light. The rods of retina have rhodopsin which is destroyed by light and is regenerated in dark with the help of Vitamin A. In deficiency states, there is difficulty in vision in dark which may lead to blindness. The cones are concerned with colour differentiation and which in turn are dependent upon vit-A.
Sources:         Fat, kidney, liver, lung, carrots, green vegetables, yellow fruits
Daily requirement:   Adult 2500 i.u. Pregnancy 6000 i.u.
Stability:   Vit-A is destroyed by U.V light, Oxygen and high temperature.




Deficiency may be due to :
(1)   Improper intake (2) Improper digestion due to  (a) low fat diet (b)  deficiency of bile salts (c)  intestine disease. (3)  Improper conversion of carotene to  Vit-A  (4) Impaired  mobilization.
Effects of Deficiency
Night and color blindness (2)  Ulceration of eyes (3)  Skin is scaly and hyper keratinized. (4)  Oral manifestation: includes (a) heperkeratinization of  oral tissues which show as white patches (b)  Metaplasia of salivary glands, may cause xerostomia (c)  there may be change in taste and smell. There has been no evidence of much important dental changes in human beings.
HYPER VITAMINOSIS-A:  Peeling off of the skin, Alopecia, coarse hair and generalized bone and joint pain. Oral mucus membrane shows atrophy, gingival inflammation and scaling of lips.
VIAMIND-D CALCIFIROL
             It is a fat soluble Vitim found in animal kingdom. Its precursor is present in plants & yeasts which can be converted to Vit-D in human beings by action of U.V. rays of sunlight.
ACTION:      It is an important vitamin and has a role in the normal grow of body through its action on bone formation and absorption of Ca & PO4  from gut and kidneys. The absorption in mediated through production of a Ca binding protein.
Vitamin D plays a part in normal  mineralization and demineralization of bones. PTH (Parathyroid hormone) exerts its action through Vit D.
Sources:  (1) From fungi   (2)  Fish liver oil (3)  Egg yolk and liver of animals etc.
Daily Dose: (1) Pregnancy and adolescence 400 i.u. (2)  Adult 100 i.u.
Hypovitaminosis D:  Causes rickets in children and ostemalacia in adults.
Rickets:  There is disruption of normal bone formation. There are areas of hypo mineralization in skulls of the patient. The normal joint cartilage cannot get mineralized giving an enlarged shape to wrists, knee joints and costochondral joints (rickety rosery), long bones (weight bearing) shows some bending:
Dental Correlation:  Two types of the diseases:
1.      Caleiferol Sensitive: No. effect on amaclogenesis or dentinogenesis has been shown.
2.      Calcified Insensitive: This condition seems to be due to a dfect of kidney tubules. Some changes in the pulp chamber and dentine have been shown. There may be delayed eruption of teeth. Loss of density of lamina dura and loss of erestal bone may be seen.
OSTEMALACIA:  This type of disease is now uncommon. It occurred in adult to Vit-D deficiency. It shows an enlargement of cortex and trabeculation of bones with some islands of osteoid tissues. Bone is soft and easy to fracture.

Hyper Vitaminosis-D
            Deposition of calcium in  various tissues e.g. lungs and kidneys may be seen.
VITAMIN E TOCOPHEROL:
Vitamin E has got following actions.
1)        Antoxident  prevents molecular oxygen attacking of plounsatured acid component  of tissue lipids and thus explains its role in tissue maintenance and weakness.
2)      In infants : Milk secretion of Vit E is more which prevents infants of destruction of erythrocytes.
3)      Prevent liver necrosis.
4)      he effects on oral and germinal layer have been demonstrated in animals but not proved in man.
VITAMIN-K
The naturally occurring K1 & K2 are fat soluble while the synthetic Vit-K is water soluble.
Actions:  It is necessary for the production and action of blood factors II, VII  & X in liver. It also plays an action in bone mineralization.
Antagonist: Dicumoral reduces oxidation reduction of Vit K and thus reduces prothrombin which leads to a defected clotting mechanism. Dicumoral is helpful in certain types of surgery and in some heart diseases.
Sources: (1) Green leaves – best sources (2) Synthetic in injection form
Requirement:           Not known
Deficiency may be caused by steatorrhoea or obstructive jaundice, which causes prolonged bleeding.
ORAL SIGNIFICANCE
Deficiency may cause gingival bleeding. Post extraction/surgical bleeding is the main problem. So Prothrombin time may be evaluated before any surgery and that must be at least 50%. If and when required, Vit K injection may be used which gives effects in 8-12 hours.
BIOTIN
A widely distributed factor in nature but may be antagonized by certain factors e.g. the rats fed on raw egg gave rise to sign of “dermatitis” retarted growth  and loss of muscle control”. The antagonizing factor is called “avidin” but this is agglutinated/ precipitated by boiling etc. so it is not harmful. Daily requirement is not known and the deficiency has not been identified clinically.

ASCORBIC ACID VIT-C
It is a white crystalline substance soluble in water but is oxidized readily and loses its potency. Oxidation may be inhibited by low pH and presence of metals like Iron & Cu and that is the reasons of Vit-C  estabillity in fruit.
Action:
The main function is its role in formation of collagen which is the main fiber of connective tissue (2)  It takes part in hydroxylation processes of many of the compounds (3)  It plays some role in iron absorption (4) Some part must be played in body’s reaction to stress as there are large quantities in adrenal cortex which are depleted during stress.
Source:  Dark green leaves, fresh fruits.
Daily Dose: Adult dose is 30-60 mg per day
Any physical and mental stress, pregnancy and lactation etc increases its demand upto 500 mg daily. Vit –C is excreted through urine
Deficiency
 Deficiency of Vitamin-C leads to “scurvy” which may be described as a disease of collagen deficiency. Acute deficiency of Vit-C causes haemorrhagic tendency due to capillary fragility due, in turn, to loss of connective tissue support in the vessel wall. Skin patechies occur around hair follicles, lower extremities and arms. Sub-periosteal haemorrhage may be evident. Anaemia may result from chronic bleeding and hemolysis.
Subacute scurvy: impaired wound healing, hyperkeratiosis,  pecechias and gingivitis with a tendency of haematoma formation.
Oral manifestations
            Oral manifestations are evident both in acute and sub-acute states. Gingivitis is the first sign with marginal bleeding, swelling and ulceration. On progression of the disease, condition worsens and bleeding occurs with slight pressure. Secondary infection may occur and mostly occurs  e.g. vincents  infection. Local factor e.g. tartar and poor oral hygiene add to the dilemma.
            Recent studies show that animal fed on low Vit-C diet are more susceptible to periodontal disease as compared to the control.
Therapeutic Dose:   300-500 mg per day
Clinical Uses:
1)       Promotion of wound bleeding
2)      Mega doses of Vita C may alleviate bone pain
3)      When used in common cold, may reduce the severity of signs and symptoms.


THIAMINE
            It is a white crystalline alcohol which is stable in heat and acid media.
Action:  It has got an important role in utilization of carbohydrates (Production and elimination of pyruvates and lactic acids). Its deficiency complications may be explained on the basis of this action.
Sources:         whole cereals, Rice, Meats and eggs etc.
Daily Requirement: is 1.5 mg per day, and as it cannot be stored in body, it is excreted through urine.
Deficiency:    (1) May be caused due to improper intakes (2)  In alcoholies (3)  Disorders of metabolisms.
ü  There is a variety of deficiency sings and symptoms.  E.g. Beri-beri, wermicker encephalopathy, Korsakoff’s syndrome.
ü  Heart failure with clear lungs, dependent edema, elevated venus pressure and enlarged heart.
ü  Beri-beri – weakness of muscles, numbness and paresthesia of legs, paralysis may occur.
ü  Wernick’s encephalopathy: apathy, confusion, loss of memory, ataxia, delirium etc,  eye signs, nystigmus, paralysis of extraoccular muscles.
All above can be corrected by parental thiamin. Initial symptoms include irritability, loss of appetite, nausea and vomiting and diarrhea due to inflammation of gut.
ORAL MANIFESTATION
Oral manifestation is rarely severe. Hypersensitivity of teeth and oral mucosa,
Enlargement of fungiform papillae of tongue. Small vesicles or cracks may be seen on
Vermilion border or commissars of lips.
VITAMIN B-2 RIBOFLAVIN
It is also called lactoflavin. It is yellow crystalline, heat stable substance and  is stored in liver, heart and kidneys.
Action: Acts as co-enzymes for dehydrogenases  and acts as carrier of Hydrogen ion.
Source : (1)  whole  cereal (2)  liver (3) Milk (4) egg etc.
Daily Requirement :  (1) adults – 1.5 mg per day (2)  during pregnancy 2.5 mg
DEFICIENCY  
Severe oral signs and symptoms are caused.
1.      Angular chelitis with more horizontal fissures and  with super added infections  (candidiasis).
2.       Glossitis-enlargement of fungi form and degeneration of flibriform papillae giving a granular appearance of the tongue.
3.      The oral mucosa may acquire publish hue (resembling cyanosis). Prolonged deficiency may cause  “ bullas lichen planus” and “ painful periodontitis ”
4.      General: Anaemia, seborhic dermatitis, conrneal vascularization.
VITAMIN B-3: NOCTANIMIDE    
            It is a white crystal, soluble in water and is stable in heat, acid and alkali.
ACTIONS:    It acts as NAD and NADP in dehydrogenesis  (carrier of hydrogen).
Sources:         (1) Whole cereals (except corn) (2) Rice (3) Liver, thin meats etc.
Daily requirement: adults require 20 mg per day and it is excreted in urine.
Deficiency: Causes pellagra which is characterized by symmetric red scaly dermatitis of the stocking and gloves areas which may darken & desquamate. Lesions are aggravated by heat and sunlight, accompanied by diarrhea, numbness and burning sensation, vertigo nervousness, progressive weakness and anorexia.
ORAL MANIFESTATION    
            There is generalized erythema of the oral mucosa; papillary atrophy of tongue with discomfort tongue may become fiery red, with ulcers on dorsum and borders. Secondary ulceronecrotic gingivostomatitits, herpes labiallis and angular cheilosis may occur.
Treatment:     of the symptom is done with 150 300 gm nicotionamider per day.
PYRIDOXINE VIT B-6    
            It is a colorless crystal which is soluble in water.
Bio functions: It plays an important action in amino acid metabolism.
Antagoist:    INAH used in treatment of tuberculosis is its antagonist.
Sources:         As thiamine & riboflavin, it is available from (1) meats (2) liver (3) cereal
Requirement:  (1) Infant 0.3 mg/d (2) Adults 2.0 mg/d
Deficiency:   Deficiency is not seen on normal food habits, due to its wide natural distribution but may occur due to alcoholism which may results in dermatitis peripheral neuropathy and a microcytic; hypochromic anemias with high serum iron levels may also be seen.
Oral Changes: Are not specific, may be like that of iron deficiency, e.g angular chelitis glossitis and generalized stomatitis.
            The Vit Bdeficiency disease run in families, so it may be called a genetic disorder
FOLIC ACID 
            A group of related compounds, bright yellow in color and is heat labile.
Sources:         Include green leafy vegetable and organ meats e.g liver.



Requirement: 50 ug/d
Deficiency:    Although it is destroyed by cooking, but gross deficiency may only be seen in elders, alcoholics or in digestive system problems etc.
            During pregnancy, in certain tumors and in process of certain cell turnover, deficiency may be seen. Certain drugs e.g trimethoprim and phenytoin may cause competitive antagonisms and thus a pseudo deficiency state may develop.
Effects:  Folic acid deficiency symptoms are similar to B6   deficiency e.g megaloblastic anemia. Oral manifestation is also similar. Severe oral ulceration beings the most prominent symptoms.
COBALAMIN VIT B12
            A group of related compounds laid cobalamin, cynocobalamin. Hdhroxy cobalamin and methyl cobalamisn are included Vit B12. Clinically cobalt is attached to certain amino acids. It is a red crystalline substance and is heat stables.
Source:  It is produced solely by bacteria and then eaten by animals. It is available to human beings from (1) Meat (2) Liver (3) Kidney (4) Egg (5) Milk
Requirement: 2-5 ug/d
Absorption: In gut, its absorption depends upon the intrinsic factor “IF” and is absorbed in ileum at certain receptors. It is stored in liver which is enough for 3-4 years.
Deficiency:  May occur due to deficiency of IF which anemia. There is initially an inflammation with rawness, tenderness, edema of mucosa and difficulty in eating. A trophy occurs withy degeneration of fungi form and filo form papilla. Recurrent ulcers of oral cavity without angular chelates may also be seen.
Supplements of Vit B-12    Corrects the symptoms like burnings and loss of taste, quickly and safely.
PANTOTHENIC AND
            It is very widely distributed in nature and its deficiency is never seen practically, it is yellow oil and is heat labile. It makes a part of coenzyme A, so helps in different reaction in a body.
ACTIONS OF CO-A
1.      It helps in oxidation of (a) glucose (b) fatty acids (c) amino acids (d) acetic acid.
2.      It helps in synthesis of (a) choline (b) triglycerides (c) phospholipids (d) bile acids (e) cholesterol
3.      It helps in detoxification of certain molecules.
Deficiency:   Occurs only in experimental animals. The signs and symptoms are (1) Alopecia (2) Graying of hair (3) Resorption  of root of teeth (4) Resorption of supporting tissue of teeth (5) Osteoporosis.
I man, it acts in combination with folic acid and biotin. 

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