What is the cause of a firm, 1 mm, mobile structure in my upper lip near my front dentures, which is not painful and has no ulcerations?

Firm Mobile Structure in Upper Lip Near Dentures

This is most likely a benign salivary gland lesion (mucocele or minor salivary gland tumor) or fibrous tissue, and you should see a dentist or oral surgeon for clinical examination and possible excision with histopathologic diagnosis.

Most Probable Diagnoses

Mucocele (Mucus Retention Phenomenon)

• Mucoceles are the most common benign lesions presenting as firm, mobile nodules in the lip, though they typically occur in the lower lip rather than upper lip 1
• These lesions result from trauma to minor salivary gland ducts, which is particularly relevant in denture wearers due to chronic mechanical irritation 1
• Mucoceles are characteristically painless, mobile, and can persist for extended periods without ulceration 1

Pleomorphic Adenoma (Mixed Tumor)

• The upper lip is the second most common site for minor salivary gland neoplasms, with pleomorphic adenoma being the most frequent benign tumor 2
• These present as firm, mobile, painless nodules that can be mistaken for other lesions and require histopathologic diagnosis 2
• Definitive diagnosis requires surgical excision and microscopic examination 2

Fibrous Lesions

• Dermatofibroma can rarely occur on the lip, presenting as a deep-seated, firm nodule 3
• Chronic irritation from dentures can produce fibrous hyperplasia or reactive tissue

What You Should NOT Ignore

Red Flags Requiring Urgent Evaluation

• Any change in size, color, or texture of the lesion warrants immediate assessment 4
• Development of ulceration, bleeding, or pain suggests possible malignant transformation 4
• Fixed (non-mobile) masses are more concerning for malignancy than mobile ones 4

Recommended Action Plan

Immediate Steps

1. Schedule evaluation with a dentist or oral surgeon within 2-4 weeks for clinical examination and palpation of the oral cavity 4
2. Remove dentures during examination to allow complete inspection of all oral surfaces 4
3. The clinician should assess denture fit, as ill-fitting dentures cause chronic trauma leading to reactive lesions 5

Diagnostic Workup

• Clinical examination with good lighting is essential to characterize the lesion's size, consistency, mobility, and relationship to surrounding structures 4
• Bimanual palpation helps distinguish salivary gland lesions from other masses 4
• Surgical excision with histopathologic examination is both diagnostic and therapeutic for small lip lesions 2, 1
• Imaging is generally not required for small, mobile lip lesions unless deeper involvement is suspected 4

Treatment Approach

• Surgical excision is the safest method for both diagnosis and definitive treatment of lip nodules, even when the diagnosis seems clinically obvious 6
• Complete excision prevents recurrence and provides tissue for microscopic diagnosis 2, 1
• For lesions related to denture trauma, addressing the mechanical cause (denture adjustment or replacement) prevents recurrence 5

Common Pitfalls to Avoid

• Do not assume a painless, non-ulcerated lesion is benign without histopathologic confirmation - pleomorphic adenomas and even early malignancies can present this way 2
• Avoid delaying evaluation beyond 4-6 weeks, as any persistent oral mass requires definitive diagnosis 4
• Do not attempt self-treatment or ignore the lesion hoping it will resolve spontaneously 1
• Ensure dentures are removed during clinical examination, as they can obscure important findings 4