Recurrent Mouth Ulcers (Recurrent Aphthous Stomatitis)

Introduction

Recurrent aphthous stomatitis (RAS), also known as recurrent mouth ulcers or canker sores, is a chronic inflammatory condition of the oral mucosa. It is characterized by the repeated appearance of painful ulcers on non-keratinized areas of the mouth. The exact cause remains unclear, but genetic predisposition, local trauma, stress, hormonal changes, nutritional deficiencies, and systemic diseases are among the contributing factors. RAS can significantly affect quality of life, making early diagnosis and effective management essential.

Etiology of Recurrent Mouth Ulcers

The exact cause of recurrent aphthous stomatitis is not fully understood. It is thought to be multifactorial, involving immune-mediated mechanisms and genetic susceptibility.
Key factors include:

• Genetic predisposition (family history in up to 46% of patients)

• Local trauma such as accidental cheek biting or aggressive toothbrushing

• Nutritional deficiencies (iron, folic acid, vitamin B12, and zinc)

• Hormonal changes (menstruation, menopause, pregnancy)

• Systemic diseases such as Crohn’s disease, ulcerative colitis, celiac disease, and Behçet’s disease

• Immune-related conditions including HIV infection

On a cellular level, RAS involves T-cell-mediated immune responses. Inflammatory cytokines such as TNF-α, IL-2, IL-6, and IL-10 play a role in tissue damage, leading to ulcer formation.

Predisposing Factors

Local Factors

• Repeated trauma to the oral mucosa

• Use of irritating dental hygiene products

• Smoking cessation (interestingly, smokers are less likely to develop RAS)

Systemic Factors

• Behçet’s disease (oral ulcers are a diagnostic criterion)

• Nutritional deficiencies leading to oral mucosa atrophy

• Hormonal imbalance (worsens during menstruation, improves during pregnancy)

• Immune deficiencies such as low CD4 lymphocytes in HIV patients

Epidemiology

Recurrent mouth ulcers affect up to 25% of the global population. They typically begin in childhood or adolescence and may persist throughout life. Minor aphthous ulcers are the most common type, while major and herpetiform types are less frequent.

Types of Recurrent Aphthous Ulcers

Minor Aphthous Ulcers

• Most common (about 80% of cases)

• Small (<5 mm), round or oval

• Heal within 1–2 weeks without scarring

• Usually appear on non-keratinized mucosa

Major Aphthous Ulcers

• Larger (>10 mm), deeper, and more painful

• Last up to 10 weeks

• Often leave scars after healing

• More common in patients with immune or gastrointestinal disorders

Herpetiform Ulcers

• Least common type

• Multiple small ulcers (2–3 mm), often clustered

• May merge into large irregular ulcers

• Heal in 1–4 weeks, sometimes with scarring

• More frequent in older women

Diagnosis

Diagnosis of RAS is primarily clinical, based on patient history and examination. In some cases, blood tests (iron, folic acid, vitamin B12) or biopsies may be necessary to rule out systemic conditions such as Behçet’s disease, HIV, or inflammatory bowel disease.

Treatment and Management

There is no definitive cure for recurrent mouth ulcers, but treatments aim to reduce pain, shorten healing time, and prevent recurrence.

First-Line Treatments

• Topical corticosteroids (triamcinolone, clobetasol, fluocinonide in Orabase)

• Chlorhexidine mouthwash to prevent bacterial superinfection

• Topical tetracycline rinse in combination with corticosteroids

Severe Cases

• Systemic corticosteroids (short-term courses, e.g., prednisone)

• Immunosuppressants (thalidomide, dapsone, pentoxifylline) for persistent, severe ulcers

Supportive Measures

• Pain relief with topical anesthetics or NSAIDs

• Nutritional supplementation (iron, vitamin B12, folic acid, zinc) when deficiencies exist

• Avoiding triggers such as spicy foods, stress, or certain dental products

Differential Diagnosis

Conditions that can mimic recurrent aphthous ulcers include:

• Behçet’s disease (oral and genital ulcers, eye involvement)

• Cyclic neutropenia (associated with systemic infections)

• PFAPA syndrome (periodic fever, pharyngitis, and adenitis in children)

• HIV-related oral lesions

• MAGIC syndrome (Sweet syndrome with mucocutaneous ulcers)

Prognosis

Recurrent mouth ulcers usually follow a cyclical pattern.

• Minor ulcers heal within 2 weeks without scarring.

• Major ulcers may take up to 6 weeks and often scar.

• Herpetiform ulcers usually resolve within 4 weeks, with rare scarring.

Although benign, severe cases can impair nutrition, hydration, and oral hygiene due to pain.

Complications

• Difficulty eating and drinking, leading to nutritional deficiencies

• Secondary infections (prevented with chlorhexidine rinses)

• Fungal infections from long-term corticosteroid use

• Reduced quality of life due to recurrent pain and discomfort

Prevention and Patient Education

• Identify and avoid triggers such as trauma, stress, and dietary irritants

• Maintain good oral hygiene

• Follow a balanced diet with adequate vitamin and mineral intake

• Avoid spicy, salty, or acidic foods during active ulcers

• Regular follow-up with healthcare providers every 3–6 months for chronic cases

Conclusion

Recurrent aphthous stomatitis is a common but challenging condition with no definitive cure. Management focuses on symptom relief, reducing recurrence, and addressing underlying conditions. With proper treatment and lifestyle adjustments, most patients can significantly improve their quality of life.