Angular Stomatitis & Mouth Ulcers Under the Tongue

Angular Stomatitis (Angular Cheilitis / Perlèche)

What It Is

Angular stomatitis presents as moist, infected, reddish-brown fissures at the corners (angles) of the mouth. Saliva leaks at the corners, and the macerated skin becomes secondarily infected.

S Das Manual on Clinical Surgery, p. 354

Causes and Risk Factors

Category	Details
Infection	Candida albicans and/or Staphylococci are the usual secondary pathogens in the fissures
Nutritional deficiency	Iron deficiency, riboflavin (B2) deficiency, folate deficiency - all cause or worsen angular cheilitis
Children	Habitual licking or rubbing of corners of the mouth - called Perlèche
Elderly / denture wearers	Reduced vertical dimension with over-closure leads to pooling of saliva at angles
Sjögren syndrome	Xerostomia causes angular stomatitis (perlèche) as a key dermatologic sign
Iron deficiency	Part of Plummer-Vinson syndrome (with glossitis, koilonychia, dysphagia)
Riboflavin (B2) deficiency	Angular stomatitis + cheilosis + glossitis + corneal vascularization
Congenital syphilis	Small radiating cracks at angles - called Rhagades (rare)

Fitzpatrick's Dermatology, p. 2937
Yamada's Textbook of Gastroenterology (Riboflavin section)
Rheumatology 2-Volume Set (Sjögren section)

Treatment

Topical antifungal/antibacterial (e.g., clotrimazole or miconazole cream) if Candida is suspected
Correct the underlying deficiency - check and replace iron, B2 (riboflavin), B12, folate
Denture adjustment in elderly patients
Zinc supplementation if zinc deficiency co-exists (can worsen iron-deficiency states)
Avoid lip-licking in children; barrier creams can help

Mouth Ulcers Under the Tongue (Sublingual / Aphthous Ulcers)

What They Are

The most common cause is recurrent aphthous stomatitis (RAS), which affects up to 20% of the population. These occur on non-keratinized mucosa - ventral tongue, floor of mouth (under tongue), buccal mucosa, and lip mucosa.

They form well-defined, shallow, circular ulcers with a white-to-gray pseudomembrane and erythematous rim.

Goldman-Cecil Medicine, p. 4149

Three Clinical Forms

Type	Size	Features	Duration
Minor aphthae	< 0.5 cm (or <10 mm)	Flat, painful, often multiple	5-14 days, heals spontaneously
Major aphthae	> 0.5 cm (>10 mm)	Raised borders, deeper, solitary	Weeks to months; may scar
Herpetiform	1-2 mm (clusters of up to 100)	Coalescent, resemble herpes - but NOT viral	10-14 days

Tintinalli's Emergency Medicine, p. (section 245)

Causes / Associated Conditions

Aphthous ulcers under the tongue are idiopathic by definition, but the following conditions must be ruled out:

Iron deficiency (aphthous stomatitis is a mucosal sign)
Folate / B12 deficiency
Celiac disease (aphthae may remit with a gluten-free diet)
Behçet syndrome (recurrent aphthae are a hallmark feature)
HIV/AIDS (larger, more persistent, more frequent aphthae)
Crohn's disease (aphthous-like ulcers with granulomatous histology)
Reactive arthritis, SLE, discoid lupus (occasional aphthae)
Trauma - ill-fitting dentures, sharp tooth edges, hot food burns
Harrison's Principles of Internal Medicine 22E, p. 305

Treatment of Aphthous Ulcers

No treatment cures recurrent aphthous stomatitis, but several reduce pain and speed healing:

First-line topical therapies:
- Topical steroids: fluocinonide gel/ointment - apply at earliest signs or with prodrome
- Chlorhexidine 0.2% mouth rinse
- Local anesthetic agents (lidocaine gel)
- Bioadhesive pastes (e.g., Orabase with corticosteroid + anesthetic)
Tetracycline/doxycycline mouth rinse - reduces severity and duration when used at onset
Systemic steroids (e.g., prednisone 40 mg/day x 3 days) for major aphthae
Laser therapy - may promote healing and pain relief, though not yet proven in clinical trials
Treat the underlying cause - correct nutritional deficiencies, manage celiac disease, review medications

Red flag: Chronic, relatively painless ulcers lasting >2 weeks, or mixed red/white patches (erythroplakia/leukoplakia), should be biopsied to exclude squamous cell carcinoma. High-risk sites include the floor of the mouth, ventral and lateral tongue, and lower lip.

Harrison's 22E

The Link Between Both Conditions

Angular stomatitis and sublingual ulcers commonly share the same root causes - especially iron deficiency, B2 (riboflavin) deficiency, and folate/B12 deficiency. When both appear together, a nutritional workup is highly warranted:

Serum iron, ferritin, TIBC, transferrin saturation
Serum B12, folate, RBC folate
Riboflavin (erythrocyte glutathione reductase)
CBC for anemia

Treating the deficiency typically resolves or significantly improves both conditions.

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