Orofacial granulomatosis: A case report of three cases may be caused by apical periodontitis

RATIONALE: Orofacial granulomatosis (OFG) is a rare disease characterized by noncaseating granulomatous inflammation. The most common clinical presentation is persistent swelling of the soft tissues in the oral and maxillofacial regions. The precise cause of OFG is unknown. Corticosteroids are the first-line and best treatment, but there is lack of uniform treatment prescription and standard. It is important to identify the pathogen in order to improve treatment specificity. PATIENT CONCERNS: Three patients presented with recurring lip swelling and cobblestone formation on buccal mucosa, complained of toothache or dental caries for many years. They had very similar and characteristic clinical signs, especially the corresponding location with infected teeth, which suffered from apical periodontitis. DIAGNOSES: The three patients were all diagnosed with typical clinical signs and non-caseating epithelioid cell granulomas histologically. INTERVENTIONS: The teeth with apical periodontitis were extracted or treated and corticosteroids were prescribed locally or/and systematically. OUTCOMES: A complete resolution of lip swelling and cobblestone formation were shown after treatment. LESSONS: This is the first report to highlight that apical periodontitis may intrigue the pathogenesis of OFG, which suggested that dental infection may be the direct and initial etiology of OFG. Removal of infected teeth should be performed as soon as possible in order to reduce the dosage of corticosteroids and occcurence rate of OFG.