What are the causes of oral aphthae (recurrent aphthous stomatitis)?

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From the Guidelines

Oral aphthous ulcers are primarily caused by a combination of immune system dysfunction, genetic predisposition, and environmental triggers, including minor trauma, stress, hormonal changes, nutritional deficiencies, and food sensitivities, as supported by the most recent expert consensus guideline for diagnosis 1. The exact cause of oral aphthous ulcers is often unknown, but they are thought to result from an abnormal immune response that causes inflammation and tissue damage in the oral mucosa. According to the expert consensus guideline, recurrent aphthous ulcers (RAU) may be caused by disturbed immune response, genetic predisposition, nutrient deficiency, oral trauma, anxiety or stress 1. Some common triggers include:

  • Minor trauma to the mouth, such as from dental work, accidental cheek bites, or aggressive brushing
  • Stress and hormonal changes
  • Nutritional deficiencies, particularly vitamin B12, folate, iron, and zinc
  • Food sensitivities, especially to chocolate, coffee, strawberries, eggs, nuts, cheese, and spicy or acidic foods
  • Certain medications like NSAIDs
  • Systemic conditions such as Behçet's disease, celiac disease, inflammatory bowel disease, and HIV/AIDS can also cause recurrent aphthous ulcers, as mentioned in the guideline 1. It is essential to identify and avoid personal triggers, maintain good oral hygiene, use toothpaste without sodium lauryl sulfate, and address any underlying nutritional deficiencies to help prevent recurrent episodes. The expert consensus guideline emphasizes the importance of a comprehensive diagnostic work-up, including detailed clinical medical history inquiry, histopathological examination, and ulceration-related systemic diseases screening, to improve diagnostic efficiency and avoid misdiagnosis or missed diagnosis 1.

From the Research

Causes of Oral Aphthous

The causes of oral aphthous ulcers are widespread and can be attributed to various factors. Some of the possible causes include:

  • Localized trauma [ 2, 3 ]
  • Genetic predisposition [ 2, 4 ]
  • Stress [ 2, 4 ]
  • Hormonal changes [ 2, 4 ]
  • Environmental factors [ 2 ]
  • Underlying intestinal disease [ 3 ]
  • Malignant disease processes [ 3 ]
  • Vitamin deficiencies, such as vitamins B12, C, and folate [ 5 ]
  • Anemia, serum iron, and folic acid deficiencies [ 4 ]

Pathophysiology

The pathophysiology of oral aphthous ulcers remains unclear, but it is believed to be a multifactorial T cell-mediated immune-dysregulated disease [ 4 ]. Various bacteria are also thought to be part of its microbiology [ 3 ].

Clinical Aspects

Oral aphthous can appear alone or secondary to numerous distinct disease processes [ 3 ]. If recurrence occurs frequently, it is called recurrent aphthous stomatitis [ 3 ]. A detailed history and thorough examination of systems can assist the physician or dermatologist in defining whether it is related to a systemic disease process or truly idiopathic [ 3 ].

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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