A 2 mm x 2 mm nodule is discovered on the attached gingiva. What is the most likely histological finding?

A small, 2 mm asymptomatic nodule on the attached gingiva in an otherwise healthy patient is most likely a focal fibrous hyperplasia (irritation fibroma), which on histology shows normal stratified squamous epithelium covering dense fibrous connective tissue with few inflammatory cells. This is the most common soft tissue lesion of the oral cavity. Serous acini would indicate a minor salivary gland tumor. Odontomas and osteomas are hard tissue lesions not typically found as gingival soft tissue nodules.