Case #8

Aug. 1, 1996
A 39-year-old female consulted her general dentist for evaluation of a white-and-red lesion located in the mandibular buccal vestibule.

A 39-year-old female consulted her general dentist for evaluation of a white-and-red lesion located in the mandibular buccal vestibule.

Joen Iannucci Haring, DDS, MS

History

When questioned about the area in the buccal vestibule, the patient claimed the white-and-red lesion had been present for approximately two days, describing it as "painful." When questioned about the teeth adjacent to the lesion, the patient said she experienced an intermittent pain in the first molar tooth, using aspirin to alleviate the pain.

The patient`s last dental visit was one year earlier. At the time of the current appointment, the patient appeared to be in an overall good state of health. No significant problems were noted during the medical history, and no medications were being taken by the patient at the time of the dental examination.

Examinations

Physical examination of the head and neck region revealed no abnormal findings. The patient`s vital signs were all found to be within normal limits. No unusual or abnormal extraoral findings were noted.

The intraoral examination revealed a large, diffuse lesion in the right mandibular vestibular sulcus. The lesion appeared to be white and red in color, extending from the second premolar to the second molar (see photograph). Further oral examination revealed no other lesions present.

Clinical diagnosis

Based on the clinical information presented, which of the following is the most likely diagnosis?

- erosive lichen planus

- erythematous candidiasis

- discoid lupus erythematosus

- traumatic ulcer

- chemical injury

Diagnosis

__ chemical injury

Discussion

A chemical injury can be described as an adverse reaction of oral tissues that results from contact with a caustic agent. The improper use of caustic agents such as aspirin, hydrogen peroxide, silver nitrate, and phenol are often responsible for chemical injury of the oral mucosa.

Chemical injury of the oral mucosa may result as follows:

- If aspirin is held in the mouth and not swallowed in an attempt to alleviate dental pain.

- If a ≥ 3 percent concentration of hydrogen peroxide is held in the mouth or applied directly to oral tissues.

- If silver nitrate or phenol is applied to a lesion or to oral tissues.

Clinical features

Aspirin, hydrogen peroxide, silver nitrate, and phenol all produce similar mucosal damage. The amount of tissue damage depends on the duration of contact and the concentration of the offending agent. If the length of exposure is brief, the oral mucosa appears white and wrinkled. As the length of exposure increases, a coagulation necrosis occurs. In such cases, the necrotic mucosa exhibits a sloughing component.

When this sloughing tissue is removed, an erosive area of underlying tissue is exposed. The amount of tissue damage correlates with the amount of pain experienced by the patient. With more severe damage, there is more severe pain.

Diagnosis and treatment

Although a chemical injury may resemble a variety of lesions, the history of chemical trauma enables the practitioner to establish a clinical diagnosis. The diagnosis of a chemical injury is dependent upon a good history. Patients must be carefully questioned about the use of common caustic agents, especially aspirin. It is imperative that the practitioner establishes a cause-and-effect relationship between the offending agent and the lesion.

In cases of a questionable patient history, a number of lesions (reticular lichen planus, candidiasis, and erosive lichen planus, for example) may be considered in the differential diagnosis. Such lesions can be diagnosed as follows: via patient history and clinical appearance (reticular lichen planus, RDH May `89), via exfoliative cytology and culture techniques (candidiasis, RDH March `94), or via a biopsy (erosive lichen planus, RDH November `90).

Superficial mucosal chemical injuries typically resolve in 10-14 days without scarring. Coverage with a topical preparation such as Zilactin® may be recommended to provide symptomatic relief. Surgical debridement may be necessary, however, in cases of extensive mucosal involvement. In order to prevent further chemical injury to oral tissues, patients must be educated concerning the caustic agent responsible for the mucosal damage and instructed to discontinue the use of the offending agent.

Joen Iannucci Haring, DDS, MS, is an associate professor of clinical dentistry, Section of Primary Care, The Ohio State University College of Dentistry.