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The mouth: mirror of maladies

Brian Mouatt
Former Chief Dental Officer
Department of Health

As President of the General Dental Council, Sir David Mason famously made the plea to dentists, "Let us put the mouth back in the body." Rightly, he felt that dentists at the time had grown away from mainstream medical practice. They were concentrating too much on the "drill and fill" aspects of their work and not enough on the whole health of the patient. It was a timely cry for common sense, and happily one to which the profession has responded.
It is easy to see why the mouth should not be neglected by any health professional. The structures and mucous membranes of the oral cavity can give us valuable information on the health and nutritional status of an individual. It is an easily accessible window onto the beginnings of the gastrointestinal tract. It contains muscles and ligaments; it is richly supplied with blood vessels and lymphatic tissue; there are a variety of bony structures, including, of course, the very specialised teeth. The salivary glands are important in maintaining a healthy mouth, producing both a viscous and a more fluid saliva. The tongue and palate are involved in the sense of taste. It is not surprising, with this array of tissues, that hints about systemic health can be discerned. There is more: through the mouth we eat, speak and communicate our feelings by smiling and other, often subtle, orofacial expressions. Perfect teeth and a film star smile are socially desirable attributes, as any glossy magazine will amply demonstrate.

What are we looking for?
What, then, should the nurse, physician or dentist be looking for as they switch on the penlight and peer into the mouth on the command of "open wide!"? First, it is helpful to consider what a normal healthy mouth is. The gums (gingivae) will be firm and pink with no bleeding. The mucous membranes of the cheeks will be smooth and slightly darker in colour. The tonsillar tissues will be compact. The tongue is covered with a pink mucous membrane consisting of many papillae and lymphoid follicles. The top surface of the tongue is rougher, especially towards the back with a speckled appearance without furrows and fissures, which are not characteristic of a healthy tongue. The teeth should be unstained and regular in appearance. Smokers give themselves away here.

The observable oral signs and symptoms of disease
Changes in the appearance of the oral tissues can have numerous causes.(1) They can range from minor ulcerations to severe disturbances associated with oral cancer. There is a range of problems associated with teething and later the eruption of the permanent teeth. Another set of signs and symptoms is associated with nutritional disorders. The haematological diseases can show themselves in the mouth, as can diabetes and other disturbances of the endocrine systems. Renal disease and the gastrointestinal diseases also give rise to oral manifestations. Add to this the more common dental disorders of dental caries (decay) and perio-dontal (gum) diseases and we can see that a careful examination of the mouth can be a worthwhile use of time. All that is needed is a wooden tongue spatula, some gauze and a good light. The most common oral signs and their symptoms are listed in Table 1 with their presenting signs.(2,3) This list is not intended to be exhaustive but may indicate when referral to a medical practitioner or dentist should be considered.


Nutritional disorders
Disturbances or aberrations having a nutritional origin generally appear in adult life. Glossitis or inflammation of the tongue is associated with a number of vitamin and essential mineral deficiencies. Telltale signs of nutritional disorders are inflamed cracks at the angles of the mouth where upper and lower lips meet - known as angular cheilosis. Often the tongue shows changes in the papillae and appears red and smooth; there may also be soreness and intraoral burning.(4)


Any painless ulcer in the mouth that lasts more than six weeks needs to be regarded with suspicion. This is especially so if it is in the floor of the mouth or the palate. Referral to a medical or dental practitioner to eliminate the possibility of oral cancer is needed. There are about 2,000 deaths in the UK from oral cancer each year; early referral can be a lifesaver.
Much more common and, mercifully, of much less significance are small recurrent painful ulcers known as aphthous ulcers. They can be single or multiple and have great nuisance value. Outbreaks associated with the onset of menstruation or the premenstrual period would seem to indicate a hormonal trigger, but men get them too, particularly at times of stress, and it is thought they are connected with adrenal function. Ulcerations are also seen in the mouth in other conditions, including:

  • Herpetic infection.
  • Crohn's disease.(5)
  • Ulcerative colitis.
  • Coeliac disease.
  • Anorexia nervosa.
  • Mercury poisoning.

The haematological diseases
Iron-deficiency anaemia shows itself in the mouth by pale buccal (cheek) mucosal tissue and a smooth glossy tongue. In leukaemia the gingivae may appear swollen and bleed easily, and sometimes there are ulcers on the palate.(6)

Xerostomia (dry mouth)
A dry mouth and swelling of the parotid glands may be associated with a fissured tongue. This may be Sjögren's syndrome, a chronic, slowly progressive autoimmune disorder.(7) Dry mouth is also associated with a range of modern medications, including the hypotensive and anxiolytic drugs. The loss of a healthy saliva flow greatly increases the risk of dental decay and is a common sequel to medication in the elderly.
Xerostomia is seen in diabetes mellitus, which may also show enlargement of the parotid glands, with altered taste and a burning mouth sensation. It is also a major cause of halitosis (bad breath), as is poor oral hygiene, alcohol and tobacco misuse. Uraemia can also give rise to an ammonia-like odour on the breath.(8) An acetone or fruity smell on the breath is also characteristic of this.

Sometimes known as oral thrush, candidiasis is often associated with the elderly, who may also be denture wearers and not maintaining adequate oral hygiene. However, it is also seen in hypoparathyroidism and renal failure. An important aspect is the appearance of an oral candidiasis as an early indication of seroconversion in HIV/AIDS.

Gastrointestinal disease
Crohn's disease is often manifest in the mouth with diffuse bumpy swelling of the lips and bleeding gums. A midline fissure in the lower lip and cheilosis at the angles of the mouth are characteristic. The oral symptoms often precede the intestinal lesions by years, so referral of suspicious cases can be very beneficial. Ulcerative colitis presents with multiple painless but quite destructive oral ulcerations on the lips, soft palate and tongue. These can cause significant scarring.

Dental diseases
Dental caries, periodontal diseases and the many other problems to be found in the mouth, together with their diagnosis and treatment, are naturally the province of the dentist, but nurses and midwives can provide a most valuable service by picking up obvious trouble at an early stage, sometimes in patients who do not perceive a need for dental care. Any change in the colour of the enamel, either white or brown spots, and inflamed swollen gums or bleeding when brushing indicates a checkup with the dentist is in order.

Preventing dental diseases
There is no great mystery about achieving a healthy mouth and preventing dental diseases. Excellent advice is available for youngsters; a good example is the leaflet Growing up with Healthy Teeth.(9) Another leaflet designed for mothers and small babies, Looking after your Baby's Teeth, is a most useful start for new parents.(10) These messages are simple - use fluoride toothpaste and reduce the frequency of "snack attacks". All those health professionals who come into contact with patients can play a vital role in getting these messages heard. It is useful to think of the two "Fs" - fluoride and frequency - and use the leaflets - they are free.

Sugar used to be blamed for all dental decay. While it is true that sugary foods and drinks can be detrimental, we now realise it is the frequency with which teeth are exposed to all types of fermentable carbohydrates, including sugar, which is important. The widespread consumption of crisps and similar starchy snacks has also become a significant challenge to the teeth. It is a fallacy to think it is simply the amount of sugar that is related to the severity of dental caries. This is because the bacteria in the mouth need only a minimal quantity of sugar to produce an acid reaction. If the saliva has time to wash away this sugar before another exposure, then the acid is neutralised and any harm can be repaired.
A constant equilibrium exists between the enamel and saliva. There is a process of demineralisation by the acid and remineralisation by saliva. If this is disturbed by frequent exposure the oral environment becomes almost permanently acidic and the enamel dissolves, leading to decay. Any acid attack will do this, hence the increasing concern dentists have with the frequent consumption of carbonated drinks, which are often very acidic. This causes erosion of the enamel and is something dentists now watch out for.
It does not need a great leap of imagination to realise that very sweet and sticky foods are more dangerous than those that are quickly cleaned from the mouth, such as fluids. Dentists talk about "clearance times": the sooner the saliva can clean the mouth, the sooner the danger period is over. Brushing with fluoride toothpaste is a very good way of helping this process. The fluoride helps the enamel to remineralise when it has been damaged by acid attack. It strengthens the enamel and reduces the acid-producing potential of the bacteria.

Nurses play a vital role in so many areas that one hesitates to add another. However, the truth is that being alert about what the mouth can show us about patients' health can sometimes be lifesaving and often helpful in catching disease at an early stage. Referral to the appropriate expert through the GP or family dentist may often be in the patient's best interests. So, let's put the mouth back in the body!


  1. Long G, Hlousek L,Doyle JL. Oral manifestations of systemic diseases. Mt Sinai J Med1998:65;309-15.
  2. Brietman R, Frost S, Roth J. Oral manifestations of gastrointestinal disease. Dig Dis Sci 1981:26;741-7.
  3. Krause M, Mahan K. Food nutrition and diet therapy. Philadelphia: WB Saunders; 1997. p. 99-143.
  4. Pizzorno JE, Murray MT, editors. Oral manifestations of nutritional status and gastrointestinal disease. A textbook of natural medicine. Seattle: John Bastyr College Publications; 1993.
  5. Williams AJK, Wray D, Ferguson A. The clinical entity of orofacial Crohn's disease. Q J Med 1991:289;451-8.
  6. Lynch MA, Ship II. Initial oral manifestations of leukaemia. J Am Dent Assoc 1967:75;932-40.
  7. Atkinson JC, Travis WD, Pillemer SR, et al. Major salivary gland function in primary Sjögren's syndrome and its relationship to clinical features. J Rheumatol 1990:17;319-22.
  8. Ross WF, Salisbury PL. Uremic stomatitis associated with undiagnosed renal failure. Gen Dent 1994:9/10;410-2.
  9. The Sugar Bureau. Growing up with healthy teeth. London: SB; 1998.  
  10. The Sugar Bureau. Looking after your baby's teeth. London: SB; 2001.

British Dental Association