DentalCare Logo

A Guide to Clinical Differential Diagnosis of Oral Mucosal Lesions

Course Number: 110

Viral Diseases

Viral diseases typically have an acute or abrupt onset of multiple lesions. Systemic manifestations (including fever, malaise, lymphadenopathy, diarrhea, lymphocytosis) may be present. It is important to realize, however, that not all patients with viral diseases have systemic manifestations. All the viral diseases mentioned below, except for infectious mononucleosis, have a vesicle stage. Vesicles rupture rapidly and are often not apparent to patients or clinicians.

Herpes simplex virus* (HSV) types 1 and 2 commonly infect skin and oral mucosa. Type 1 preferentially involves mucosa and skin above the waist, while type 2 usually infects the genital area, but occasionally the pattern is reversed. Individuals infected with HSV will harbor latent virus in regional nerve ganglia for the remainder of their lives. Primary symptomatic infection with HSV involving the mouth is called primary herpetic gingivostomatitis*. Although primary herpes is most common in children, it can certainly occur in older adults without antibody to HSV

Image 1: Primary Herpetic Gingivostomatitis
Image 1: Primary Herpetic Gingivostomatitis
Image 3: Primary Herpetic Gingivostomatitis
Image 4: Primary Herpetic Gingivostomatitis

Images of Primary Herpetic Gingivostomatitis:

Signs and symptoms of primary herpes include abrupt onset of fever, malaise, tender lymphadenopathy of the head and neck, and vesicles and ulcers anywhere on oral mucosa, the pharynx, lips and perioral skin. The gingiva is typically enlarged and erythematous. The lesions are painful, making it difficult to eat and drink. The lesions resolve spontaneously, usually within 10-14 days.

A number of systemic and topical antiviral drugs are available for patients needing treatment. An important consideration for drug therapy is that the earlier the treatment is initiated, the better the outcome. Supportive and symptomatic treatment includes maintaining hydration, especially in children, and systemic and topical analgesics.

The best documented causes of recurrent herpetic lesions* are ultraviolet radiation, mechanical trauma, and immunosuppression. Recurrent herpes has vesicles and ulcers occurring on keratinized mucosal surfaces. The lesions are grouped in a tight cluster. Often a sudden prodrome of pain, tingling, or numbness precedes the onset of lesions. The frequency of recurrence varies with the individual. Resolution of lesions varies from 1 to several weeks but is constant for each person. Since herpetic lesions resolve spontaneously within a relatively short period of time, many patients do not request or require treatment.

Image: Herpes Labialis

Herpes Labialis

Image: Recurrent Herpetic Lesion

Recurrent Herpetic Lesion

Varicella (chickenpox)* is the primary infection with the varicella-zoster virus. The disease begins with malaise, fever, pharyngitis, and lymphadenopathy. A pruritic skin rash begins on the face and trunk and spreads to the extremities. The skin lesions begin as vesicles which rupture and form crusts. They occur in successive waves or crops. Oral lesions may occur as vesicles which rupture to form non-painful ulcers. Varicella is usually a relatively mild, although annoying, infection in immunocompetent children. It tends to have more severe clinical features in adults. It can be quite serious in immunocompromised patients. Treatment is usually supportive and symptomatic in immunocompetent children. Antiviral medications, such as acyclovir, famciclovir, and valacyclovir, are useful in immunocompromised patients, adults, and infants. A vaccine for varicella is available. It appears to be highly effective, but the duration of immunity is not known.

Image: Varicella (chickenpox)

Varicella (chickenpox)

Image: Herpes zoster

Herpes zoster

Herpes zoster, or shingles*, represents reactivation of the varicella-zoster virus in a person previously infected. Zoster tends not to recur as frequently as herpes simplex. Zoster typically begins with the abrupt onset of pain, tingling, or numbness in the distribution of a sensory nerve. It is important to note that neuralgia associated with the prodrome stage of zoster may initially involve one or more teeth in a quadrant, thus simulating a toothache. Patients reporting pain in teeth that show no clinical or radiographic abnormalities should NOT have dental procedures performed on them in an attempt to eliminate the pain.

Neuralgia in the prodrome stage of zoster is followed by vesicles and ulcers similar in appearance to those caused by herpes simplex. Because the lesions follow a nerve distribution, they extend to the midline and stop. The vesicles and ulcers of zoster usually resolve within several weeks. However, the neuralgia may be extremely severe and persist for weeks to months. Antiviral drugs, when given early in the course of the disease, appear to be beneficial in reducing the neuralgia.

Herpangina*, most commonly caused by Coxsackievirus A, presents with acute onset of mild fever, malaise, lymphadenopathy, pharyngitis, nausea and diarrhea. Many cases have no systemic manifestations. Oral lesions include vesicles and ulcers of the posterior oral mucosa, especially the soft palate and tonsillar pillar areas. Management includes analgesics, rest and encouraging the patient to drink plenty of fluids. Herpangina is typically a mild disease and resolves within approximately a week.

Image: Herpangina
Image: Herpangina


Hand, foot and mouth disease* is an infection caused by Coxsackievirus A or B. It has abrupt onset of mild fever and pharyngitis. Oral lesions consist of vesicles and ulcers that may involve any area of oral mucosa. Skin lesions consist of erythematous macules and vesicles of the palms, soles, fingers and toes. The disease typically resolves within a week. Management includes analgesics, rest and encouraging the patient to drink plenty of fluids. The prognosis is good.

Image: Hand, foot and mouth disease

Hand, foot and mouth disease

Infectious mononucleosis* is a viral infection caused by Epstein-Barr virus. Infections in children may be asymptomatic. Symptomatic patients may demonstrate pharyngitis, cervical lymphadenopathy, fever, malaise, enlargement of liver and spleen, and sometimes a skin rash. Oral lesions are sometimes present and include palatal petechiae, hyperplasia of palatal tonsils, necrosis of surface mucosa overlying tonsils, and necrotizing ulcerative gingivitis. Diagnosis is confirmed by serologic testing for heterophil antibodies. Infectious mononucleosis is treated with rest and analgesics. It usually resolves within 4 to 6 weeks.

Rubeola (measles) is a potentially serious viral infection which can cause fever, malaise, cough, lymphadenopathy, pharyngitis, and an erythematous maculopapular skin rash. Oral lesions occur early in the disease and consist of red macules with white centers on the buccal mucosa, known as Koplik spots. The most important aspect of rubeola is the potential for complications to arise, including pneumonia and encephalitis. Vaccination is critically important. For infected patients, rest and supportive care is indicated. Rubeola is currently rare because of mandatory vaccination programs.

To view the Decision Tree for Oral Mucosal Lesions, click on one of the options shown.

To view the Decision Tree for Oral Mucosal Lesions, click on one of the options shown.