Acanthosis nigricans A rare paraneoplastic condition where papillomatous oral lesions are seen often in patients with internal malignancy.

Acatalasia Autosomal recessive defect in the enzyme catalase, which normally removes reactive oxygen species, such as hydrogen peroxide, from tissues. Severe periodontal destruction and oral ulceration can result.

Achondroplasia (chondrodystrophia fetalis) An autosomal dominant condition in which endochondral ossification is reduced. The most common form of short-limbed dwarfism – patients have disproportionately short limbs, bowed legs, kyphosis, prominent buttocks and abdomen, and trident hands with short fingers. The skull is relatively large, having prominent frontal, occipital and parietal bones. The middle third of the face can be hypoplastic with nasal bridge depressed and a class III type malocclusion. The foramen magnum is often narrow and spinal cord compression can occur. Joints can be of limited mobility and the pelvic inlet narrow.

Acrodermatitis enteropathica A rare genetic disorder of zinc metabolism causing mouth ulceration and candidosis, rash around orifices, and alopecia.

Actinic prurigo (AP) A chronic, pruritic skin disease caused by an abnormal reaction to sunlight.

Actinomycosis A rare infection with Actinomyces israelii, below the mandibular angle (not lymph nodes) that may follow jaw fracture or tooth extraction. Prolonged therapy, usually with penicillin, is indicated.

Acute necrotizing (ulcerative) gingivitis A non-contagious anaerobic gingival infection associated with overwhelming proliferation of Borrelia vincentii and fusiform bacteria. Predisposing factors include smoking, viral respiratory infections and immune defects, such as in HIV/AIDS. Uncommon, except in resource-poor groups, this typically affects adolescents and young adults, especially in institutions, armed forces, etc., or people with HIV/AIDS.

Characteristic features include severe gingival soreness, profuse bleeding, halitosis and a bad taste. Interdental papillae are ulcerated with necrotic slough. Malaise, fever and/or cervical lymph node enlargement (unlike herpetic stomatitis) are rare. Cancrum oris (noma) is a very rare complication, usually in debilitated children. (p. 404)

Diagnosis is usually clinical. Smear for fusospirochaetal bacteria and leukocytes; blood picture occasionally. Differentiate from acute leukaemia or herpetic stomatitis. Manage by oral debridement, metronidazole (penicillin if pregnant) and oral hygiene.

Amelogenesis imperfecta A rare genetic defect of enamel formation due to mutations in AMELX, ENAM, and MMP20 genes, with a wide variety of patterns. All teeth are equally affected, as are other family members. Diagnosis is from clinical features (Fig. 57.1, Table 57.1). Fluorosis, tetracycline staining, dentinogenesis imperfecta and oculodentodigital dysplasia may need to be differentiated. Management requires restorative dental care.

Amyloidosis The deposition in tissues of amyloid – an eosinophilic hyaline material, with a fibrillar structure on ultramicroscopy. Amyloid can be identified via Congo red stain under fluorescent or polarized light, thioflavine T stain under fluorescent light, or immunoreactivity with antibodies for immunoglobulin light chains.

Primary (including myeloma-associated) amyloidosis: associated with deposits of immunoglobulin light chains. Manifestations include macroglossia and oral petechiae or blood-filled bullae (secondary purpura).

Secondary amyloidosis: seen mainly in rheumatoid arthritis and ulcerative colitis, rarely affects the mouth, and is associated with deposits of AA proteins.

Diagnose from biopsy; blood picture; raised ESR, CRP or PV and marrow biopsy; serum proteins and electrophoresis; urinalysis (Bence–Jones proteinuria: Ch. 56); skeletal survey for myeloma. Manage by chemotherapy (melphalan, corticosteroids or fluoxymesterone).

Angina bullosa haemorrhagica (localized oral purpura) Blood blisters in the mouth or pharynx, mainly on soft palate, seen in absence of any immunological or platelet-associated cause. Seen mainly in older people, the aetiology is unclear, though there are occasional associations with use of steroid inhalers. There is rapid onset, with breakdown of the blister in a day or two to an ulcer. Diagnose from clinical features, although it may be necessary to confirm haemostasis is normal; and rarely to biopsy to exclude pemphigoid. Manage by reassurance. Topical analgesics may provide symptomatic relief.

Angiomas See haemangiomas.

Angiomyoma A rare benign hamartoma involving blood vessels and muscle.

Ankyloglossia (tongue-tie) An uncommon genetic condition which results in the lingual fraenum anchoring the tongue tip, restricting tongue protrusion and lateral movements. Oral cleansing (but not speech) is impaired. Differentiate from tethering by scarring. Management is surgery (fraenectomy) if severe.

Branchial cyst A lymphoepithelial cyst that may arise from enclavement of salivary tissue in a lymph node, or from the cervical sinus. It usually becomes apparent in the third decade. It requires excision.

Bullous pemphigoid An autoimmune disease usually with widespread crops of tense, fluid-filled blisters on the skin. The diagnosis is confirmed by biopsy. Bullous pemphigoid is treated with prednisolone (enteric-coated).

Caries Dental caries can occur on any tooth surface exposed to the oral environment, but not surfaces retained within bone. There are four factors in the aetiology: a tooth surface (enamel or dentine); cariogenic (or potentially caries-causing) bacteria in dental plaque; fermentable carbohydrates; and time. The specific bacterial species believed to cause caries include Streptococcus mutans and Lactobacilli. Particularly for root caries, the most closely associated bacteria are Lactobacillus acidophilus, Actinomyces viscosus, Nocardia spp., and Strep. mutans. Sugars (sucrose, glucose, fructose) are metabolized to acetic, lactic, formic and succinic acids. Different individuals are susceptible to different degrees depending on tooth shape, oral hygiene, and the flow and buffering capacity of their saliva.

Carotid body tumour A slow-growing, but malignant neoplasm of chromaffin cells that both invades locally and metastasizes. It presents as a mass over the internal carotid artery and transmits the carotid pulsation. It must be resected.

CATCH22 Stands for cardiac abnormality, abnormal facies, T-cell deficit due to thymic hypoplasia, cleft palate, and hypocalcaemia due to hypoparathyroidism, caused by a chromosome 22 defect.

Cheek biting (morsicatio buccarum) Common and seen in adults mainly, especially anxious patients, and those with other psychologically related disorders, e.g. temporomandibular pain–dysfunction syndrome, it is also rarely caused by self-mutilation, seen in psychiatric disorders, learning disability, Lesch-Nyhan syndrome (Ch. 56) and some rare syndromes with insensitivity to pain. Abrasion of the superficial epithelium leaves whitish fragments on reddish background. The lesions are invariably restricted to the lower labial mucosa and/or buccal mucosa near the occlusal line on one or both sides.

Chemical burns Can be caused by various chemicals or drugs; notably aspirin put in the sulcus to try to relieve toothache, or cocaine. A white lesion with sloughing mucosa is seen. Diagnosis is by history and clinical features.

Chikungunya fever A mosquito-borne arboviral illness similar to dengue fever; causes arthralgia and mouth ulceration

Chondroma A benign tumour, rare in the jaws. The anterior maxilla, mandibular symphysis and the coronoid and condylar processes are the most common sites. Chondromas are typically found in the older patient and form slow-growing, painless masses. Provided surgical excision of these masses is complete, recurrence is unlikely.

Chondrosarcomas These tend to affect the older patient and, although isolated cases arise from chondromas, most arise de novo. The behaviour is very unpredictable, but many grow rapidly and produce extensive local destruction. Radical surgery, the only means of eradicating the tumour, can be difficult as the edges may not be apparent clinically or radiographically. Multiple local recurrence is common and the prognosis is worse than for osteosarcoma.

Chorea Consists of a writhing movement of continuous abrupt and intermittent movements that flow randomly from one part of the body to another. Chorea may affect the head and neck, especially in tardive dyskinesia. This is usually a late (hence tardive) complication manifesting as non-random, focal patterned or stereotyped movement induced by dopamine receptor blocking drugs, such as metoclopramide, phenothiazines or butyrophenones, and is somewhat similar to oromandibular dystonia. Senile chorea, including edentulous dyskinesia or orodyskinesia, is found in 16% of the edentulous.

Chronic ulcerative stomatitis This is similar to erosive lichen planus, with ulcers and erosions affecting mainly the buccal or lingual mucosae, but sometimes the gingivae. The lesions and clinically normal mucosa have a distinct pattern of a particulate stratified squamous-epithelium-specific (SES) antinuclear antibody (ANA) on direct immunofluorescent examination of perilesional tissue, and patients can have circulating ANA. Hydroxychloroquine is effective therapy.

Cleidocranial dysplasia (dysostosis) A rare autosomal dominant condition, or mutation. Clinical features include exaggerated transverse diameter of cranium, delayed fontanelle closure, multiple wormian bones, frontal and parietal bossing, depressed nasal bridge, maxillary hypoplasia, underdeveloped paranasal sinuses, high arched palate (? cleft), delayed or failed tooth eruption, multiple supernumerary teeth, dentigerous cysts, aplastic or hypoplastic clavicles (shoulders can be approximated), short stature and other skeletal anomalies.

Diagnosis is from the family history and ability to bring together the shoulders; jaw, skull and skeletal radiography.

Management is to leave unerupted teeth alone unless there are complications. Eruption of permanent teeth is retarded and dentigerous cysts are frequently found. Supernumerary teeth are common in cleidocranial dysplasia, especially in the anterior mandible. The crowns of the teeth are normal, but the roots can be short, thin and lack acellular cement. Surgery is often necessary.

Coeliac disease Coeliac disease is a reaction to gluten, ingestion of which activates immune cells in the small intestine, which trigger inflammation and local damage, disrupting food absorption. Untreated coeliac patients lose weight, develop deficiency syndromes such as anaemia, and experience symptoms such as diarrhoea. Dental hypoplasia and oral ulceration may result. Diagnosis is confirmed by malabsorption, blood tissue transglutaminase antibodies and villous atrophy on jejunal biopsy. Gluten is found in wheat, barley and rye, which means that many dietary staples, such as bread, many breakfast cereals and foods like pizza and pasta, can no longer be eaten.

Congenital epulis A rare reactive process seen on the alveolus of a neonate.

Constricted pupils Constricted pupils (miosis) can be caused by sympathetic nerve lesions, cholinergic drugs (e.g. pilocarpine or neostigmine) or opiates (heroin, etc.). Thus, heroin addicts may be recognized by ‘pin-point pupils’. Raised intracranial pressure is the most important cause of pupil constriction and is noted when the pupil also becomes non-reactive owing to pressure on the oculomotor nerve. It may occur after head injury, intracranial haemorrhage or brain tumour.

CREST syndrome Calcinosis, Raynaud disease, oesophageal involvement, sclerodactyly and telangiectasia (see scleroderma, p. 406).

Cri-du-chat syndrome Short arm of chromosome 5 deletion, resulting in microcephaly, hypertelorism, and laryngeal hypoplasia causing a characteristic shrill cry.

Crystal deposition diseases (‘gout’) A term used to encompass diseases that produce crystals in joints (e.g. gout, chondrocalcinosis, secondary gout caused by cytotoxic therapy) including the temporomandibular joint. Gout itself is an uncommon disorder of metabolism in which excessive levels of uric acid in the blood and other body fluids crystallize out in synovial fluid causing acute inflammation. The patient complains of a painful, swollen joint and ‘pan-meniscal crepitation’ is elicited on movement. Acute attacks are often preceded by a ‘binge’ of dietary or alcohol excess or ‘starvation’, trauma or unusual physical exercise, surgery or systemic illness. In chronic gout, tophi are frequently felt in the cartilage of the pinna of the ear. Diagnosis is clinical, but usually confirmed by a leukocytosis, raised ESR, CRP or PV raised serum urate level and aspiration biopsy for examination under polarizing light for crystals of urate (or pyrophosphate in pseudo-gout). Imaging is not often particularly helpful, since the appearance resembles osteoarthritis. Treatment must not be restricted just to the local treatment of the TMJ. NSAIDs should be started. Colchicine is effective. Gout is usually treated prophylactically with allopurinol. Dietary advice and weight control are also important.

Cyst A pathological cavity having liquid, semi-liquid or gaseous contents. It is frequently, but not always, lined with epithelium. Cysts of the jaws mostly arise from odontogenic epithelium, and are relatively common lesions (Ch. 45). Non-odontogenic developmental cysts are uncommon and were said to form from entrapment of epithelium during the fusion of embryological processes, but this embryological concept has now been discarded. The lining of these cysts is either stratified squamous epithelium or pseudostratified ciliated columnar (respiratory) epithelium. Non-odontogenic cysts include the following:

Cystic hygroma A developmental anomaly of lymphatics presenting as a swelling of the neck seen before the age of 2 years. It may extend into the mediastinum and/or tongue. Cystic hygroma is usually surgically removed.

Dentinogenesis imperfecta A rare autosomal-dominant disorder in which the dentine is abnormal in structure and, hence, translucent (Fig. 57.2), and poorly attached to enamel. All teeth are affected, but primary teeth are more severely affected than permanent teeth. In the permanent dentition the teeth that develop first are generally more severely affected than those that develop later. The teeth:

There are three types of dentinogenesis imperfecta:

Differentiate mainly from amelogenesis imperfecta, tetracycline staining and dentine dysplasia. Management is by restorative dental care.

Dermatitis herpetiformis An uncommon chronic skin disorder associated often with gluten-sensitive enteropathy, affecting mainly middle-aged males. Symmetrical papulovesicular eruptions on extensor surfaces. Oral lesions of vesicles and/or desquamative gingivitis, similar to pemphigoid typically follow skin lesions. Biopsy of perilesional tissue, with histological and immunostaining examination are essential to diagnosis, showing IgA deposits at the papillae. Jejunal biopsy often indicated. Dapsone is the main therapy – sulfamethoxpyridazine and sulfasalazine are alternatives. A gluten-free diet can minimize disease activity and can reduce or avoid the need for drugs.

Dermatomyositis A rare autoimmune disorder that occasionally presents with oral ulcers and erythema of the tongue, palate or gingivae.

Dermoid cyst A rare developmental cyst that presents as a doughy painless swelling in the midline floor of mouth and needs to be differentiated from ranula and cystic hygroma. Diagnosis is by aspiration, but there is a risk of infection. Management is by surgical removal.

Desquamative gingivitis A fairly common problem in which the gingivae show chronic desquamation and is a term that denotes a particular clinical picture and not a diagnosis in itself. Many of the patients are middle-aged women. Desquamative gingivitis is mainly a manifestation of:

Some patients make no complaint, but others complain of persistent gingival soreness, worse when eating spices, or acidic foods, such as tomatoes or citrus fruits. Most patients are seen only when vesicles and bullae have broken down to leave desquamation, and the clinical appearance is thus of erythematous gingivae, mainly labially, the erythema and loss of stippling extending apically from the gingival margins to the alveolar mucosae. The desquamation may vary from mild almost insignificant small patches to widespread erythema with a glazed appearance. In addition to a full history and examination, biopsy examination and histopathological and immunological investigations are frequently indicated. Conditions which should be excluded include:

The treatment of desquamative gingivitis consists of:

Corticosteroid creams used overnight in a soft polythene splint may help.

Dilated pupils (mydriasis) Can be caused by parasympathetic lesions affecting the third nerve, Holmes–Adie syndrome (Ch. 56), Horner syndrome (Ch. 56), anticholinergic drugs (e.g. atropine or similar drugs), sympathomimetic drugs (e.g. adrenaline, cocaine). Users of cocaine or crack cocaine may thus have dilated pupils.

Drug addiction (illegal drug use) This is increasingly common, particularly in urban areas. Addicts in need of a ‘fix’ will often falsely complain of severe pain or injury. Disturbed behaviour in a drug addict may be caused by withdrawal symptoms and the patient may need compulsory detention. If an addict is admitted to the ward, contact a licensed psychiatrist for heroin or cocaine to be given for addicts. The most serious problems in the management of addicts include:

Dysarthria (disordered speech) Normal speech involves a complex series of muscles, particularly the muscles of respiration, larynx, pharynx, palate, tongue and lips and, like all voluntary muscle activity, is under control from higher centres, both pyramidal and extrapyramidal. The act of speaking is a highly coordinated sequence involving articulation and phonation under direct control of the vagus, glossopharyngeal, hypoglossal and facial nerves. Conditions affecting the tongue, palate, pharynx, larynx or these nerves or their central connections, or sensory nerves, can lead to disturbed speech. However, speech also involves a wide range of acquired skills, deficiencies of which impede interpersonal communication irrespective of any other impairment in language usage.

Deranged speech can be due commonly to drugs (including alcohol), CNS disorders as in learning disabilities, cerebral palsy, parkinsonism, delirium or dementia; loss of voice due to laryngeal disease or paralysis (dysphonia); or defects in articulation because of paralysis, rigidity, tissue loss or scarring, or involuntary movements of tongue or palate. The most common oral cause of dysarthria is immobility of the tongue after a lingual block local analgesic injection, trauma to the tongue, scarring, diseases affecting the tongue (such as carcinoma) or foreign bodies (such as in oral piercing). Spastic dysarthria is usually caused by cerebrovascular disease affecting the motor cortex (causing pseudobulbar palsy), extrapyramidal disease, such as parkinsonism, or drugs, such as phenothiazines; basal ganglia disease causes choreic dysarthria; cerebellar disease causes ataxic dysarthria. Alcohol also has this effect. Paralytic dysarthria is less common, but may be caused by medulla oblongata disease (bulbar palsy), cranial nerve lesions affecting nerves VII, IX, X, XI or XII, myopathies, such as myasthenia gravis. Patients with persistent dysarthria should be referred for a neurological opinion.

Dyskinesias Abnormal movements of the tongue or facial muscles, sometimes with abnormal jaw movements, bruxism or dysphagia. Involuntary tongue protrusion and retraction, and facial grimacing are common dyskinesias. They differ from dystonias mainly in that muscle spasm is less prominent, but they may be difficult to differentiate clinically. They are usually caused by extrapyramidal disease, such as athetosis, or drugs. Most dyskinesias resolve within 4 weeks of stopping any causal medication. If not, treat with anti-parkinsonian drugs (e.g. benzhexol), baclofen, benzodiazepines, dopamine depletors (reserpine or tetrabenazine), calcium channel blockers, clozapine, buspirone, α-adrenergic agonists, vitamin E or botulinum toxoid.

Dysphasias Disturbances of language use (or aphasias), and may be caused by brain disease, such as stroke or after head injury, in which there is loss of production and comprehension of speech and language.

Dystonias A group of uncommon neurological diseases characterized by abnormal movements, such as sustained and patterned contractions producing abnormal postures, repetitive twisting or squeezing.

Epidermolysis bullosa A rare genetically-determined disorder related to a defect in the epidermolysis bullosa antigen in the epithelial basal lamina, leading to blistering after trauma, and scarring, which may cause severe disability, such as limb deformities, microstomia, ankyloglossia and trismus. Enamel hypoplasia may be seen. Diagnosis is from the family history and a biopsy to exclude other blistering diseases. Management includes careful attention to oral hygiene. Trauma should be minimized, and drugs such as phenytoin may help reduce the blistering.

Epidermolysis bullosa acquisita A rare non-inherited chronic mechano-bullous disease characterized by autoantibodies directed against type VII collagen. Clinically, bullae are frequently induced after mechanical irritation. The diagnosis should be made on the history, clinical features, histopathological, direct and indirect immunofluorescent examination. Biopsy of perilesional tissue, with histological and immunostaining examination are essential to the diagnosis. Topical corticosteroids effectively control gingival lesions. Systemic corticosteroids alone or in association with immunosuppressive agents and dapsone are suggested treatments.

Exfoliative cheilitis (tic de levres) An uncommon condition affecting the lip vermilion, characterized by continuous production and desquamation of unsightly, keratin scales which, when removed, leave a normal lip beneath (Fig. 57.3). The aetiology is unknown, but some cases may be factitious.

Familial holoprosencephaly Congenital malformation of the forebrain and midface: microphthalmia, hypopituitarism and hypertelorism.

Fibro-osseous lesions A group of disorders of unknown aetiology, composed of fibrous and ossified tissue. The main disorders include Paget disease of bone, fibrous dysplasia and cherubism and the ossifying fibroma.

Fissured lip Lip fissures may appear especially where there is exposure to adverse environments (Fig. 57.4), or where the lip swells as in Down syndrome (Ch. 56) or cheilitis granulomatosa (Ch. 46).

Fissured (plicated or scrotal) tongue An extremely common genetic condition, the dorsum has deep irregular fissures, but is normally papillated (Fig. 57.5). A fissured tongue may also be seen in Down syndrome or Melkersson–Rosenthal syndrome (Ch. 56). There are associations with erythema migrans in particular. The diagnosis is usually clear cut. The lobulated tongue of Sjögren syndrome (Ch. 50) must be differentiated.

Fluorosis The condition of enamel defects caused by high levels of fluoride. High levels in drinking water are uncommon in the developed world, but are particularly common in parts of the Middle East, India and Africa. Fluorosis affects many teeth:

Diagnosis is from history, clinical appearance and data about fluoride content of drinking water. It is necessary to differentiate from amelogenesis imperfecta and tetracycline staining. Management of severe forms is by the use of veneers or crowns.

Foliate papillitis The foliate papillae are found on the posterolateral border of the tongue, at the junction of the anterior two-thirds with the posterior third. The size and shape of the foliate papillae are variable and occasionally they swell if irritated mechanically or if there is an upper respiratory infection, and this is termed ‘foliate papillitis’. Located at a site of high predilection for lingual cancer, they may give rise to unnecessary concern about cancer.

Furred tongue Coating of the tongue is quite commonly seen in healthy adults, particularly in edentulous patients, those who are on a soft, non-abrasive diet, those with poor oral hyg/>