What are aphthous (canker) ulcers?

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From the Guidelines

Aphthous ulcers are best approached with a comprehensive diagnostic workup to rule out underlying conditions, and treatment should focus on promoting healing and managing pain, with consideration of the patient's overall medical history and potential for invasive fungal infections, as seen in the case of a 72-year-old woman with a history of angioimmunoblastic T-cell lymphoma 1.

When diagnosing aphthous ulcers, it is crucial to consider the patient's medical history, including conditions such as tuberculosis, diabetes, and intestinal diseases, as well as any history of radiotherapy, chemotherapy, medication, or drug abuse 1. Further examinations, including maxillofacial CT, otolaryngology consultation, nasal spiral CT, and nasopharyngoscope, may be necessary to rule out underlying conditions such as bone destruction or invasive fungal infections 1.

For patients with suspected invasive fungal infections, detection of 1-3-β-D-glucan and galactomannan can be useful, and treatment with antifungal medications such as caspofungin may be effective 1. In cases where the diagnosis is unclear, diagnostic treatment with low-dose and short-term oral glucocorticoids, a second biopsy, or multi-disciplinary team consultation may be necessary 1.

Key considerations in the management of aphthous ulcers include:

  • Promoting healing and managing pain
  • Ruling out underlying conditions such as invasive fungal infections
  • Considering the patient's overall medical history and potential for underlying conditions
  • Using diagnostic tests such as 1-3-β-D-glucan and galactomannan to detect invasive fungal infections
  • Treating invasive fungal infections with antifungal medications such as caspofungin

In terms of specific treatments, topical medications containing benzocaine or protective pastes like Orabase may provide immediate relief, while prescription options such as triamcinolone dental paste or dexamethasone elixir may be effective for larger or more painful ulcers. However, the most recent and highest quality study 1 suggests that a comprehensive diagnostic workup and consideration of the patient's overall medical history are crucial in the management of aphthous ulcers.

From the Research

Definition and Classification of Aphthous Ulcers

  • Aphthous ulcers are painful ulcerations located on the mucous membrane, generally in the mouth, less often in the genital area 2.
  • Three clinical forms of aphthous ulcers have been described: minor aphthous ulcers, herpetiform aphthous ulcers, and major aphthous ulcers 2.
  • Oral ulcers can be related to a wide range of conditions that constitute the differential diagnoses of aphthous ulcers 2.

Causes and Risk Factors

  • Recurrent aphthous stomatitis (RAS) is often idiopathic but can be associated with gastro-intestinal diseases, nutritional deficiencies, immune disorders, and rare syndromes 2.
  • Aphthous ulcers are believed to be involved in a combination of genetic predisposition, local trauma, stress, hormonal changes, and certain environmental factors 3.
  • Hard, acidic, and salty foods and toothpastes containing sodium lauryl sulfate should be avoided, along with alcohol and carbonated drinks 4.

Treatment and Management

  • Currently, treatment of aphthous ulcers is palliative and symptomatic 2.
  • Topical treatments (topical anesthetics, topical steroids, and sucralfate) are the first line therapy 2.
  • Colchicine associated with topical treatments constitutes a suitable treatment of most RAS 2.
  • Thalidomide is the most effective treatment of RAS but its use is limited by frequent adverse effects 2.
  • Antiseptic agents and local anesthetics should be tried first; if these are ineffective, topical corticosteroids should be used 4.
  • In severe cases, local measures can be combined with systemic drugs, e.g., colchicine, pentoxifylline, or prednisolone 4.

Diagnosis and Differential Diagnosis

  • Every oral solitary chronic ulcer should be biopsied to rule out squamous cell carcinoma 2.
  • A solitary palatal ulcer can be related with necrotizing sialometaplasia 2.
  • Oral lesions similar to aphthous ulcers may be present in several systemic diseases 5.
  • Behçet's disease is a chronic, inflammatory, disease whose main clinical feature is recurrent bipolar aphthosis 2.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

[Aphthous ulcers and oral ulcerations].

Presse medicale (Paris, France : 1983), 2016

Research

The treatment of chronic recurrent oral aphthous ulcers.

Deutsches Arzteblatt international, 2014

Research

Aphthous ulcers.

Dermatologic therapy, 2010

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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