Problems in the Mouth

This article is intended as a general overview of a large topic, with links to available resources to allow further enquiry where necessary.

The differential diagnoses for the clinical scenarios presented are far from complete and other diagnoses may need to be considered, depending upon the specific details of a patient's presentation. It should, however, be useful as a quick reference guide to the sorts of diagnoses that commonly cause oral problems in primary care.

Where there is doubt as to the nature of an oral pathology it is wise to seek further advice from a dental general practitioner, oral surgeon, ENT specialist or a physician if it is suspected that oral problems may be a manifestation of systemic disease.

A sore mouth is usually caused by mucosal inflammation and/or ulcer formation. Mouth ulcers are extremely common and can be due to a number of reasons. The list of possible causes of sore mouth is extremely long but the more common causes are given below:¹

• Oral cancer
• Idiopathic:
  • Recurrent aphthous stomatitis
• Infective:
  • Herpetic stomatitis
  • Varicella-Zoster virus (as chickenpox or shingles)
  • Hand foot and mouth disease
  • Oral candidiasis
• Dermatological:
  • Lichen planus
  • Pemphigus and pemphigoid
  • Erythema multiforme and Stevens-Johnson syndrome
  • Dermatitis herpetiformis
• Haematological:
  • Anaemia
  • Leukaemia
  • Neutropenia
• Gastroenterological:
  • Coeliac disease
  • Crohn's disease
  • Ulcerative colitis
• Rheumatological:
  • Systemic lupus erythematosus
  • Behçet's syndrome
  • Sweet's syndrome (febrile neutrophilic dermatosis)
  • Reiter's disease
• Pharmacological/iatrogenic:
  • Cytotoxics and radiotherapy
  • Nicorandil
  • NSAIDs
  • Pancreatin
  • ACE inhibitors
  • Many others

Aphthous ulcers

These are also referred to as canker sores, aphthous stomatitis, RAS (recurrent aphthous stomatitis), ROU (recurrent oral ulceration). This condition tends to start in childhood or adolescence and leads to recurrent small, round or ovoid ulcers with circumscribed margins, erythematous haloes and yellow or grey floors. They affect at least 20% of the population and their natural course is one of eventual remission.¹ More detail on their nature, suggestive features and the management issues can be found in the record on Mouth Ulcers.

Herpetic disease

• Gingivostomatitis² - primary infection of herpes simplex virus type 1 (HSV-1) tends to occur in children under 5 years old. Infection occurs through intimate contact (e.g. saliva) and viral shedding goes on from 4 to 60 hours following onset of symptoms (incubation period is 2-12 days). It may well be asymptomatic but patients who do present tend to do so with gingivostomatitis in children and as pharyngotonsillitis or a mononucleosis (glandular fever) - type illness in adults.There may be prodromal symptoms include fever, nausea, malaise, headache and irritability. This self-limiting condition can be adequately managed symptomatically with:
  • Analgesia (e.g. paracetamol)
  • Good fluid intake
  • Avoidance of salty or acidic foods
  • Topical benzydamine may be helpful for pain relief
  • Chlorhexidine mouthwash should minimise secondary infection
  • Lip barrier preparations (e.g. vaseline®) can be helpful
  Steps should be taken to minimise transmission:
  • Avoid touching the lesions - if this is necessary such as after applying lip cream, wash hands afterwards
  • Avoid kissing and oral sex until the lesions have healed
  • Avoid sharing items which come into contact with the lesions
  If children are well, they do not need to be excluded from school or nursery. Referral is appropriate if the symptoms do not heal within 14 days, if the patient is immunocompromised or pregnant and if there is a risk of dehydration.
• Cold sores² - this is the reactivation of latent HSV-1 which has remained dormant in the trigeminal ganglion. Cold sores are common and result in recurring symptoms in 20-40% of young adults who are seropositive for HSV-1. This is a self-limiting condition (7-10 days) which can be managed symptomatically as with gingivostomatitis (above) with the same precautions needed to minimise the risk of transmission. Topical antiviral treatment is widely available and may affect the course of the current episode if applied in the prodromal phase but they do not cure the patient or prevent further episodes. Prophylactic use is ineffective. Immunocompromised patients need referral for specialist advice on management; opinion is divided with regards to pregnant women but it is safer to refer, particularly if she is at the end of her pregnancy.
• Intra-oral herpetic infection - this tends to cause multiple, small pinpoint ulcers that heal over the course of a month or so. The lesions may begin as small vesiculo-bullae. Herpes simplex virus may also cause a severe stomatitis. Topical NSAIDs in spray or mouthwash formulation along with systemic antiviral therapy may be used to treat the condition.³

Oral candidiasis⁴

This fungal infection of the oral mucosa is usually caused by Candida albicans (although it can be caused by other candida too). Oral thrush refers to pseudomembranous candidiasis; other forms include acute erythematous oral candidiasis (acute atrophic oral candidiasis), denture stomatitis (chronic erythematous oral candidiasis or chronic atrophic oral candidiasis) and chronic plaque-like oral candidiasis (chronic hyperplastic oral candidiasis).This occurs where there is an immature or a suppressed immune system e.g. severe illness, extremes of age, HIV infection, chemotherapy or when taking oral or topical corticosteroids or immunosuppressive therapy. It tends to cause:

• Generalised soreness of the mouth (this ranges from mild to very severe), often with associated angular cheilitis.
• There may be an alteration in the sense of taste.
• With oral thrush, there will be adherent white plaques on the oral mucosa that are difficult to remove and leave behind an inflamed and painful base that is prone to bleed.
• Denture stomatitis presents with less pain but marked redness in the denture area and can affect up to 65% of denture wearers.

Management involves:

• Assessment of predisposing risk factors.
• Assessment of other risk areas in diabetics and immunocompromised individuals (oesophageal candidiasis and superficial infection of the skin and genitalia).
• Treat with topical miconazole (patients under 2 years old: topical miconazole gel) or oral fluconazole for people over 18 years with superficial candidiasis in other sites.
• For those on warfarin, sulphonylureas, tolbutamide or statins, use topical nystatin suspension (unlicensed).
• A Cochrane review has found strong evidence supporting the use of systemic anti-fungals in the treatment and prophylaxis of oral candidiasis in patients with cancer.⁵
• The azole group of drugs appear to most effective in HIV-positive patients (oral fluconazole is suggested) although the evidence-base is somewhat confused.⁶
• Refer anyone suspected of having oesophageal candidiasis (arrange emergency admission), people with previously undiagnosed or inadequately managed diabetes or HIV infection and people with denture stomatitis.

Burning mouth syndrome⁷

This idiopathic condition is characterised by a burning sensation in the tongue or other parts of the mouth in the absence of medical or dental causes. Local and systemic factors (such as infections, allergies, ill fitting dentures, hypersensitivity reactions and hormone and vitamin deficiencies) may cause the symptom of burning mouth and should be excluded before diagnosing burning mouth syndrome. Dryness and taste disturbance are also often present. On waking, the pain is usually trivial or not present and worsens throughout the day. It predominantly affects post-menopausal women. There are putative associations with chronic anxiety or depression, type 2 diabetes and salivary dysfunction but none of them have been proven. Benzodiazepines, tricyclic antidepressants or anticonvulsants may be effective treatments in some. Topical capsaicin has been used occasionally.⁸

Geographic tongue (benign migratory glossitis)⁹

This is a common idiopathic condition affecting up to 10% of children and adults, twice as much in females as males. It presents with coastline-like red areas (hence its name) of atrophy of filiform tongue papillae in patterns that may change over the course of a few hours. The tongue is often fissured and it may be sore or asymptomatic. Resolution of the affected area is spontaneous with a return to normal tongue architecture but changes go on to appear elsewhere on the tongue. If lesions occur at other mucosal sites, the condition is termed erythema migrans. Its cause is not clearly identified.¹⁰ Geographic tongue, or a similar pathological lesion, is thought to be associated with Reiter's disease and psoriasis.¹ There is no known effective therapy but zinc supplementation has been used with some anecdotal evidence of benefit.¹ Patients also report that avoidance of spicy foods helps symptomatically.

• It is a little more unusual to encounter problems specifically confined to the mouth in children although there is a rising incidence of dental caries and gingival disease - see dedicated record (link at the end of this record).
• One cause of sore mouth to consider in children that is often overlooked is Kawasaki disease, especially if there is marked irritability of the child, with fever and rash/desquamation of the perineum and/or extremities.
• Hand, foot and mouth disease is another important acute cause of sore mouth in children.
• Herpetic gingivostomatitis has been discussed above as has oral candidiasis.
• Cancrum oris (noma) is a serious condition characterised by a rapid, painless and extensive necrosis of oral cavity that can involve cheek, nose, palate and bones. It almost always occurs in the context of poor oral hygiene and in developing countries. It may be preceded by excessive salivation, malodour from the mouth, grey discoloration and gingival ulcer formation. See dedicated record.

See also our record on Salivary Gland Disorders.
Swellings in the mouth may be due to a wide range of conditions.¹¹ The list below outlines some of the commoner causes:

• Non-pathological – e.g. unerupted teeth, pterygoid hamulus, parotid papillae, lingual papillae
• Developmental – e.g. haemangioma, lymphangioma, maxillary and mandibular tori (bony exostoses), hereditary gingival fibromatosis, Von Recklinghausen's neurofibromatosis
• Inflammatory – e.g. abscess, granulomatosis, sarcoidosis, pyogenic granuloma, Wegener's granulomatosis
• Traumatic – e.g. epulis, fibro-epithelial polyp, denture granulomas
• Cystic – e.g. eruption cysts, developmental cysts, infective cysts, ranula (mucocele of the minor salivary glands)
• Fibro-osseous – e.g. fibrous dysplasia, Paget's disease
• Hormonal – e.g. pregnancy epulis, pregnancy gingivitis, oral contraceptive pill gingivitis
• Drugs – e.g. phenytoin, calcitonin, calcium-channel blockers
• Tumours – benign and malignant
• Haematological – e.g. leukaemias, lymphomas
• Miscellaneous – angio-oedema, amyloidosis

Mucocele is a common swelling of the inner surface of the lower lip and is due to obstruction of small salivary glands. When it occurs on the floor of the mouth it is known as a ranula and often has a bluish tinge. It is wise to refer any persistent swelling in the mouth for an oral surgical assessment due to the danger of missing a case of oral carcinoma or another significant pathology. Biopsy may be needed to determine the cause of a persistent intra-oral swelling.

Red lesions of the oral mucosa are usually inflammatory in nature but may also be malignant, especially erythroplasia. The table below lists some important causes of red lesions of the oral mucosa.

Erythroplasia/erythroplakia

Although relatively rare, this is an important diagnosis not to miss. It tends to affect older patients above 60 years of age. The lesion is velvety in nature and usually affects the mouth, the ventrum of the tongue, or the soft palate. It may be associated with C. albicans, the human papilloma virus and the Epstein-Barr virus. It has also been linked to heavy alcohol consumption and significant tobacco chewing when it occurs on the larynx. It has a high malignant potential and patients suffering from it should be referred to an oral surgery service for biopsy of the lesion.

Erythematous candidiasis

This is a relatively common cause of a sore, red mouth, particularly in older patients. It can be precipitated by corticosteroids, antimicrobials, HIV infection, xerostomia, diabetes and smoking. It is usually treated with antifungal preparations, particularly fluconazole, and smoking cessation. The wearing of ill-fitting or inadequately cleaned dentures is associated with the condition. Some patients with dentures (particularly those who wear them at night) may experience redness of the palate that can occasionally be sore and is due to chronic infection of their denture with C. albicans. This is sometimes termed denture sore mouth. It is often found concurrently with angular stomatitis. It should be treated by thorough cleansing of the denture by overnight soaking in chlorhexidine or hypochlorite solution (hypochlorite can discolour metal dentures so avoid its use in this case). Miconazole gel or amphotericin lozenges should be used 4 times daily for up to a month. Resistant cases may need to be treated with systemic fluconazole. The denture may need to be adjusted if it is no longer fitting correctly.¹¹

Leucoplakia was a term that was formerly used to describe all white lesions of the oral mucosa but should now be reserved for those of unknown cause or those that are considered to be pre-malignant. A small but significant proportion of such lesions will progress to become malignant.¹² Most white lesions in the mouth are relatively benign keratoses caused by friction from teeth, cheek biting or tobacco smoking. However, a malignant lesion of the oral mucosa should be excluded and this usually requires biopsy.¹¹ A variety of treatments have been used to try and encourage resolution of leucoplakic lesions and prevent malignant transformation but as yet there is no convincing proof of their efficacy and further research is needed.¹² Significantly dysplastic lesions are usually treated by excision by conventional means or laser but there is a significant recurrence rate.¹³

The list below outlines the common and important cause of white lesions in the mouth:

• Keratosis of known/unknown cause
• Oral carcinoma
• Infective cause:
  • Candidiasis
  • Hairy Leucoplakia (HIV-related)
  • Syphilitic keratosis
  • Human papilloma virus
• Mucocutaneous conditions:
  • Lichen planus
  • Systemic lupus erythematosus
  • Rarer inherited conditions such as white sponge naevus

Oral lichen planus

This inflammatory condition commonly presents in older patients, with white patches affecting the mucosa of the mouth or tongue bilaterally. Oral lichen planus is more difficult to treat and typically lasts longer than that on the skin (about one in five people who have oral lichen planus also have affected skin). It is important to refer these cases for biopsy and follow-up to exclude or monitor for malignancy, although as yet it is not clear if surveillance of such cases is definitely associated with better outcomes.¹⁴ Once the diagnosis is confirmed, there is actually no cure. Various therapies have been tried (e.g. ciclosporins, retinoids, steroids and phototherapy) but the evidence of their superiority over placebo is weak and so treatment is mainly aimed at reducing pain.¹⁵

Candidiasis

This is another common cause of white patches in the mouth. Typically there is an adherent white patch that can be removed with some difficulty leaving an erythematous or bleeding base. See above section on oral thrush under sore mouth heading for more details.

Hairy Leucoplakia¹⁶

These benign lesions are associated with the Epstein-Barr virus. they are characterised by unilateral or bilateral non-painful white lesions which may vary in appearance from smooth, flat, small lesions to irregular "hairy" or "feathery" lesions with prominent folds or projections. They are found on the margins, dorsal or ventral surfaces of the tongue or on buccal mucosa. They may be either continuous or discontinuous along both tongue borders and they are often not bilaterally symmetric. Lesions are adherent and only the most superficial layers can be removed by scraping. This condition is often found in immunocompromised patients, particularly in HIV-infection or AIDS (especially if these patients smoke more than a pack of cigarettes a day). Viral load, oral candidiasis, previous use of fluconazole and systemic acyclovir are probable risk factors for the condition in HIV-positive patients and it appears to be prevented by the use of anti-retroviral medication.¹⁷ Once developed, it tends to resolve spontaneously over time but depending on the individual case, active treatment may be considered. Options include systemic anti-viral therapy (e.g. acyclovir 800 mg 5 times a day), topical therapy (e.g. 1-2 applications of podophyllin resin 25% solution) or more rarely, ablative therapy (e.g. cryotherapy).

• Blue/purple patches may be haemangiomas (will blanch with pressure), Kaposi's sarcoma (will not blanch) or purpura/ecchymoses (non-blanching, usually smaller lesions). Other rarer causes include heavy-metal toxicity or Peutz-Jegher's syndrome.
• Brown or black lesions may be caused by staining from fillings (so-called amalgam tattoo) or naevi (freckles) but could rarely be due to melanoma, so referral for biopsy should be considered.
• If the tongue is furred and brown/black and/or appears hairy (particularly on its posterior portion), this is likely to be due to poor oral hygiene. It can be a problem in edentulous patients, those with a soft diet, those who smoke, those who are fasting or ill or are using antimicrobials or chlorhexidine long-term. At its extreme this condition is termed black, hairy tongue. The condition is treated by improving oral hygiene, brushing the tongue or using a tongue scraper, increasing dietary fruit and roughage (pineapple is useful) and the use of sodium bicarbonate mouthwash.¹¹
• Generalised pigmentation of the oral mucosa can be a normal feature in people of dark-skinned races. Certain medications (e.g. phenothiazines, zidovudine, minocycline) and smoking can rarely cause it, as can Addison's disease or ectopic production of ACTH e.g. by carcinoma of bronchus.

Also known as xerostomia, this is characterised by a dry mouth sensation ± difficulty in speaking or swallowing due to thick or sticky saliva. Individuals may also complain of halitosis. A wide range of conditions may cause this problem. Relatively common causes are listed below:

• Psychogenic causes including burning mouth syndrome (see above)
• Age-related¹⁸
• Anticholinergic medication (particularly tricyclic antidepressants)
• Aspirin¹⁹
• Diuretics¹⁹
• Sjögren's syndrome
• Head and neck radiotherapy
• Any cause of salivary gland dysfunction (see our record on salivary gland disorders - link above)
• Menopause

There is is no way of preventing the problem but there are a number of products designed to provide moisture and comfort, usually gels or sprays. Patients are also advised to use fluoride toothpastes as dry mouth predisposes individuals to tooth decay. Regular visits to the dentist are also important.

This may be due to acute or occult illness such as chest infection, bronchiectasis, lung abscess, appendicitis, gastroenteritis, undiagnosed diabetes or foetor hepaticus due to liver disease. In the long-term it is more usually caused by poor oral hygiene and associated gingivitis/periodontal disease. Smoking cessation, better oral hygiene, use of antiseptic mouthwashes and regular dental follow-up should help improve the condition. Please refer to our dedicated record on Halitosis for further information.

This is an area with a huge range of possible causes, and does not form part of the routine training of medical staff, so it is usually best dealt with by a dental general practitioner. However, current NHS dentistry provision is increasingly patchy, so such problems are presenting to medical primary care and emergency departments more frequently.
Please refer to our dedicated record on Dental and Periodontal Diseases for more detail.