PULPITIS and PERIAPICAL DISEASE

Infection and suppuration inside the tooth is called "pulpitis", the common cause of throbbing toothache.

When the infection spreads to involve the periodontal ligament, "periapical disease" will result, and the patient will describe pain on chewing.

Suppurative disease here in the apical periodontium is the very painful "apical abscess" (alveolar abscess), which may drain out through bone to erupt as a "gum boil". Bad cases can turn into osteomyelitis, etc., etc.

From here, cellulitis may spread to the floor of the mouth ("Ludwig's angina", which can spread to occlude the upper airway) or even the cavernous sinus (with thrombosis, etc.)

Chronic periapical disease produces the "periapical granuloma" (actually necrotic tissue walled off by fibrosis) which may subside into a "radicular cyst," etc.

PERIODONTAL DISEASE: The major cause of loss of teeth in persons over 35.

{12366} periodontal disease ("gingivitis ")
{12430} bad periodontal disease ("pyorrhea")
{12432} periodontal disease

Calculus, especially in the gingival crevice (sulcus), causes inflammation of the gingival tissues ("gingivitis"), which often extends to the periodontal ligament, alveolar bone, and cementum of teeth ("periodontitis"). This does irreversible damage and results in the loss of teeth.

The tissue response to calculus is markedly increased during puberty and pregnancy and in other disease involving the gingiva (scurvy, monocytic leukemia, thrombocytopenia.)

The inflammatory infiltrate is mostly lymphocytes and plasma cells. Really bad periodontitis with pus formation used to be known as "pyorrhea". A few people still use this as a generic term for periodontal disease.

BACTERIAL INFECTIONS

Necrotizing gingivitis (Vincent's angina, trench mouth) is a mixed infection with Borrelia vincentii and Fusobacterium. There is necrosis of the gingival margins and interdental papillae as well as signs and symptoms of systemic illness.

Usually this affects young adults with poor oral hygiene who are under stress (college students, military recruits, soldiers in wartime.)

{12433} "trench mouth" (necrotizing gingivitis)

"Noma," a terrible necrotizing stomatitis seen in some patients with kwashiorkor, is the most severe form.

* Fusobacterium necrophorum is the appropriately-named micro-organism responsible for noma (Am. J. Trop. Med. 60: 223, 1999). Noma review: NEJM 354: 221, 2006.

The disease is not contagious and responds to penicillin.

Gonorrhea, syphilis, tuberculosis, and actinomycosis are other notable causes of oral infections.

It's good to remember here that bacteria will enter the bloodstream whenever the dentist cleans or fixes your teeth ("oral sepsis"). To keep strep viridans from growing on the inner surfaces of the heart, people with valve problems or other heart deformities should receive antibiotic coverage at these times.

NON-PATHOLOGY OF THE TONGUE

There are a variety of poorly-understood changes that involve the tongue papillae, typically for no apparent reason. These include "geographic tongue" (travelling areas of papillary and epithelial atrophy), "transient lingual papillitis" (one papilla gets red, swollen, and sore, nobody's got a clue why: Oral Surg. Or. Med. Or. Pa. 82: 441, 1996), "median rhomboid glossitis" (loss of papillae in the middle), "hairy tongue" (long filiform papillae, not the same as "hairy leukoplakia"), and "scrotal" (brain-like) tongue.

BENIGN TUMORS AND QUASI-TUMORS

Papilloma: a viral wart.

Fibrous hyperplasia: a quasi-tumor of fibroblasts that develops at sites of longstanding injury (i.e., ill-fitting dentures)

Pyogenic granuloma: a mass of granulation tissue sticking out of the gum between the teeth. This is neither "pyogenic" (has nothing to with pus or germs), nor a "granuloma" (no epithelioid cells). In the mouth, this is most common in pregnant women. It's probably a less-fibrous version of the irritation fibroma described in "Big Robbins".

* Granular cell myoblastoma (the "cell of origin" is really the Schwann cell) is an important lesion to remember because of overlying pseudoepitheliomatous hyperplasia which can look like squamous cell carcinoma to the unwary. These tumors commonly occur on the tongue.

MALIGNANT TUMORS AND RELATED CONDITIONS: Mouth and throat cancer comprises 2-5% (estimates vary widely) of all cancers.

Leukoplakia is a term applied to any hyperkeratotic lesion from histologically benign to dysplastic to malignant, that doesn't have another cause. (* Lichen planus and the less-common identifiable hyperkeratotic diseases are by definition excluded.)

You can distinguish this from candida and mouth-crud because it can't be scraped off.

HPV-16 (the same nasty strain that so often causes cancer of the cervix and penis) is common in these lesions. Having it on board may double your risk (NEJM 344: 1125, 2001).

* Yes, it's probably gotten from performing oral sex: J. Inf. Dis. 189: 686, 2004.

If "leukoplakia" is not particularly keratotic, but vascular-inflamed and hence reddish, it is called "erythroplakia". These lesions are almost always dysplastic.

It is strongly correlated with tobacco, particularly some (not all) "smokeless" varieties (Oral Surg. 73: 750, 1992. "I see right where you put your tobacco.") Snuff is much more obnoxious than chewing tobacco; especially the latter seldom produces cancer, and even snuff is far safer than smoking.

{12361} oral leukoplakia
{21206} leukoplakia where the guy keeps his snuff

Squamous cell carcinoma is by far the commonest mouth cancer (95+%, includes "verrucous carcinoma").

Most common sites are lower lip, tongue, and floor of mouth (probably in that order).

Risk factors include tobacco (both smoked and smokeless), alcohol, herpes simplex virus I, and syphilis (the last is mostly of historic interest.) The first three appear to act synergistically. Sunlight is bad for the lower lip.

The farther posterior the lesion is located in the mouth, the less well differentiated (and more aggressive) it is likely to be.

Unless the lesion is excised while very small, the prognosis is generally poor.

There are three subtypes:

1. Keratinizing.

2. Non-keratinizing. These often have Epstein-Barr (herpes 4) on board too.

3. "Lymphoepithelioma", a poorly-differentiated squamous carcinoma rich in lymphocytes, with Epstein-Barr invariably found in the squamous cancer cells. This is very common in the Far East and is presently blamed on a combination of Epstein-Barr infection and pickled fish and pickled vegetables. (* I told the trendoids that kimchee was probably bad for...)

{12169} squamous cell carcinoma of the lip
{38614} carcinoma of tongue, patient

Doctors: Don't forget to look at the oral mucosa, including under the tongue, when you do a physical exam. Apparently most physicians don't, which is why this gets diagnosed so late (Cancer 72(S3): 1061, 1993.)

* Victims of throat cancer include Babe Ruth and Beatle George Harrison.

ORAL LICHEN PLANUS

This is a common chronic disease of the skin and oral mucosa. In the mouth, it appears as lacy, white patches. The problem seems to be type IV immune injury to the basal cells.

{12360} oral lichen planus
{12604} oral lichen planus, good filigree

APHTHOUS STOMATITIS ("canker sores")

An extremely common disease in which painful ulcers occur repeatedly on the oral mucosa, often during times of stress or following trivial injury.

The ulcers are large infarcts caused by a local immune-complex vasculitis The pathogenesis apparently involves streptococcal (* sanguis, others) antigens others).

*I treat aphthous ulcers by melting a hydrocortisone tablet against each one; this isn't FDA approved. Topical tetracycline is supposed to work for the secondarily-infected ones. And consider a therapeutic trial of thiamine: Oral Surg Oral Med 82: 634, 1996).

Herpes virus does not cause aphthous stomatitis (recurrent intra-oral herpes lesions are uncommon.)

Patients with Crohn's disease (regional enteritis, ileitis, etc.) tend to get aphthae in the mouth, rectum, elsewhere.

Whenever you see several aphthae, you must think of neutropenia and check the white count!

Beçet's syndrome: aphthous ulcers, genital ulcers, and iridocyclitis, caused by autoimmunity against heat-shock proteins (Lancet 350: 28, 1997). One treatment is thalidomide (Pediatrics 103: 1295, 1999; NEJM 336: 1487, 1997), an anti-TNF drug. Another is sucralfate (Arch. Derm. 135: 529, 1999; Ann. Int. Med. 128: 494, 1998).

Aphthae are a major nuisance for many AIDS patients. Thalidomide has been a great help to these people (NEJM 336: 1487, 1997).

{21234} aphtha
{21619} aphtha

More mouth ulcers: agranulocytosis, lupus, pemphigus vulgaris, mucous membrane pemphigoid, erythema multiforme and variants

VIRAL INFECTIONS

Herpetic stomatitis is a primary infection with Herpes simplex type I. Nasty little blister-ulcers cover the lips and oral mucosa. This is a disease of children and young adults, with peak age 1-3 years. (Most people meet herpes simplex but most people never get this.)

Vesicles and ulcers, primarily on the gingiva. Systemic illness is unusual, and the lesions heal in a few weeks.

{12114} herpes simplex I, primary infection

Herpes labialis (cold sores, fever blisters) is recurrent lesions caused by Herpes simplex type I. These blisters usually last a few days, then dry up and vanish after a few more. They can be uncomfortable.

The virus is mysteriously reactivated by injury, fever, stress, hormonal chaos, UV light, and so forth.

Keep your ungloved fingers away from herpes lesions or you may catch it.

You remember how to spot herpes perikaryons (multinucleate cells) on Tzanck prep.

{21239} herpes simplex, recurrent, severe

Herpangina is not a herpes infection at all, but a vesicular eruption centered on the anterior tonsillar pillars. The etiologic agent is usually Coxsackie A virus (sometimes others.)

{21249} herpangina
{21640} herpangina

Also remember varicella-zoster, warts.

FUNGAL INFECTIONS OF THE MOUTH

Candida infections of the oral mucosa appear as white patches of mycelia that invade the superficial underlying tissues ("thrush"). You can scrape it off and confirm your diagnosis under the microscope. It is common in babies, diabetics, and immunosuppressed patients.

{05273} oral candidiasis ("thrush")
{09386} oral candidiasis ("thrush")
{12364} oral candidiasis

Any pathogenic fungus can involve the mouth (South American "blasto" often results from a man picking his teeth with a piece of wood in the jungle).

Salivary Gland Exhibit
Virtual Pathology Museum
University of Connecticut

DISEASES OF THE SALIVARY GLANDS (Med. Cli. N.A. 83: 197, 1999)

Causes of salivary gland enlargement include bacterial infection, mumps, Sjogren's, cirrhosis, and many other systemic diseases. Most salivary gland enlargement is non-neoplastic.

Mucocele develops from distended minor salivary glands. By the time the lesion gets excised, the epithelial elements are usually gone, and the lesion is a mass of mucus rather than a "mucous cyst."

Big ones under the tongue which retain an epithelial lining are called "ranulas", because of a fanciful comparison to a frog's throat.