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30Nutritional de ciencies

Patients with nutritional de ciencies are rarely seen in Britain. Susceptible patients are the elderly living on a scanty diet, food cranks and severe alcoholics living on a grossly unbalanced diet. Malabsorption syndromes (Ch. 29) are another cause.

Several oral conditions of doubtful cause, such as periodon-tal disease or glossitis, have been ascribed to vitamin de cien-cies, though patients have been otherwise healthy and well-fed. In such cases, giving vitamin preparations brings bene t only to the multibillion pound vitamin industry. Vitamin de cien-cies are not a contributory cause of dental caries.

VITAMIN DEFICIENCIESThe effects of speci c de ciencies are summarised in Table 30.1.

Vitamin A de ciency

In rats, vitamin A de ciency has severe effects on secretory epithelium. Columnar cells become squamous in type and keratinised. Dental development is severely affected and secre-tory cells of salivary glands also become squamous and kerat-inised. However, there is no evidence that vitamin A de ciency causes such changes in humans.

Successful treatment of keratotic plaques (leukoplakias) with retinoids (vitamin A derivatives) has been claimed but not con rmed. The toxic effects of these drugs are severe and they are teratogenic. Epidemiological studies have suggested an association between low vitamin A intake and oral and other cancers, but there is growing doubt whether beta-carotene is bene cial or harmful.

Ribo avin (B2) de ciency

Ribo avin de ciency can occasionally result from a malab-sorption syndrome. In severe cases, there is typically angular stomatitis, with painful red ssures at the angles of the mouth, and shiny redness of the mucous membranes. The tongue is commonly sore. A peculiar form of glossitis in which the tongue becomes magenta in colour and granular or pebbly in appearance, due to attening and mushrooming of the papillae, may be seen but is uncommon. The gingivae are not affected. Resolution follows within days when ribo avin (5 mg three times a day) is given.

Ribo avin is ineffective for the commonly seen cases of glossitis and angular stomatitis, which are rarely due to vita-min de ciency.

Nicotinamide de ciency (pellagra)

Pellagra, which affects the skin, gastrointestinal tract and nervous system, is rare in Britain but may occasionally result from mal-absorption or alcoholism. Weakness, loss of appetite and changes in mood or personality are followed by glossitis or stomatitis and dermatitis. The tip and lateral margins of the tongue become red, swollen and, in severe cases, deeply ulcerated. The dorsum of the tongue becomes coated with a thick, greyish fur which is often

Table 30.1 Effects of speci c vitamin de ciencies

De ciency Systemic effects Oral effects

Vitamin A Night-blindness, Uncon rmed contri- xerophthalmia bution to leukoplakia and cancer

Thiamin (B1) Neuritis and cardiac failure None

Ribo avin (B2) Dermatitis Angular stomatitis and glossitis

Nicotinamide Dermatitis, CNS Glossitis, stomatitis disease, diarrhoea and gingivitis

Vitamin B12 Pernicious anaemia Glossitis, aphthae

Folic acid Macrocytic anaemia Glossitis, aphthae

Vitamin C Scurvy (purpura, delayed Gingival swelling and wound healing, bone bleeding lesions in children)

Vitamin D Rickets Hypocalci cation of teeth (severe rickets only)

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heavily infected. The gingival margins also become red, swollen and ulcerated and generalised stomatitis may develop.

Vitamin B12 de ciency

This disease, unlike the others described in this section, is pri-marily a defect of absorption (Ch. 29). It is exceptionally rare for it to be caused by dietary de ciencies (veganism).

Folic acid de ciency

De ciency can result from malnutrition but is more often seen in pregnancy, or as a result of malabsorption or drug treatment (particularly with phenytoin) (Ch. 35). Women are advised to take folic acid supplements preconceptually with the aim of reducing the risk of neural tube defects. It also appears that multivitamin preparations containing folic acid may reduce the risk of orofacial clefts.

Vitamin C de ciency

Scurvy, once common among crews of sailing ships, is now exceedingly rare. In Britain, scurvy may very occasionally be seen among elderly people with an inadequate income, or in those devoted to eccentric diets. The main features of scurvy are dermatitis and purpura and, in advanced cases, anae-mia, delayed healing of wounds and swollen bleeding gums may develop (Fig. 30.1). In children, bone formation may be disturbed.

There is no evidence that de ciency of vitamin C plays any part in periodontal disease except in frank scurvy and there is no correlation between low plasma ascorbic acid levels and gingivitis. There is no justi cation for giving ascorbic acid to healthy patients with periodontal disease.

Though it may be thought that scurvy is of historical interest only, a 24-year-old engineer was reported in 1983 to have the

disease in classical form including swollen, bleeding gums. He had lived largely on peanut butter sandwiches, recalled having eaten an apple 4 years previously but could not recall ever hav-ing eaten an orange.

It has been suggested that massive doses of ascorbic acid prevent or ameliorate the common cold. This is unproven and the effect, if any, is marginal. Moreover, cessation of mega-dose intake of ascorbic acid can lead to rebound de ciency and scurvy. In one bizarre case, intravenous injection of no less than 80 g of ascorbic acid proved to be lethal. This really does seem to be carrying prevention too far.

Nevertheless, giving children vitamin C-rich fruit syrups is common. An incidental effect of this can be gross caries of the anterior teeth (Fig. 30.2).

Vitamin D de ciency

De ciency of vitamin D during skeletal development causes rickets (Ch. 10).

A rich source of vitamin D is sh liver oils, but small amounts are also present in eggs and butter. In strong sunlight, vitamin D can be synthesised in the skin. In Britain, margarine is forti ed with vitamins A and D, but requirements are small except during bone growth and pregnancy.

Rickets is now rare, but immigrants in the North of Britain are at risk. Contributory factors are lack of sunlight, a high-carbohydrate diet and possibly also the use of wholemeal our (as in chupattis) containing factors which impair calcium absorption. However, there is no basis for the idea that dental caries is due to poor calci cation of the teeth and giving vita-min D and calcium for dental caries is valueless. There are also dangers associated with raising childrens intake of vitamin D. Some are sensitive to this potent drug and hypervitaminosis D causes hypercalcaemia and renal calcinosis. Dental defects (hypocalci cation) are a feature only of exceptionally severe rickets (Ch. 2).

Fig. 30.1 Scurvy. There is gross periodontal destruction with deep pock-eting and mobility of several teeth resulting from the combination of poor oral hygiene and de ciency of vitamin C. (See also Ch. 10.)

Fig. 30.2 Gross dental caries of the anterior teeth due to over-indul-gence in sugar-rich vitamin C syrup.

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ANOREXIA NERVOSA AND BULIMIAAnorexia nervosa is, in simple terms, an eating disorder par-ticularly affecting young females, in which there is determined and persistent avoidance of food leading to emaciation and occasionally death. It is typically ascribed to fear of obesity and a distorted body image.

Bulimia is the term given to binge eating alternating with self-induced vomiting or purging to control excessive obes-ity, but emaciation is not usually achieved. In a single eating binge up to 20 000 calories may be consumed and there may be addiction to drugs or alcohol also.

SUGGESTED FURTHER READINGNowak R 1994 Beta-carotene: helpful or harmful? Science

294:500501Robb ND, Smith BGN 1996 Anorexia and bulimia nervosa (the

eating disorders): conditions of interest to the dental practitioner. J Dentistry 24:716

Oral and perioral effects of anorexia and bulimia are parotid swelling (sialadenosis) and dental erosion due to vomiting. Dentists may be able to identify such signs before medical intervention becomes imperative.

Cawson's Essentials of Oral Pathology and Oral Medicine