Intraosseous Adenoid Cystic Carcinoma Mimicking Endodontic Periapical Lesion Along With Orofacial Pain: A Case Report

ABSTRACT A 57‐year‐old patient with temporomandibular disorder and toothache underwent root canal treatments on teeth 42–31 by an endodontist. Despite these treatments, the patient experienced persistent pain radiating to his ears and sought evaluation by another endodontist. No notable facial or intraoral swelling nor paresthesia was observed; however, he reported difficulty with swallowing and trismus. A large periapical radiolucent lesion was identified spanning from tooth 42 to 32, and root resorptions were observed at the apices of teeth 42, 41 and 31. The initial diagnoses for teeth 42, 41, and 31 were previously treated and symptomatic apical periodontitis. Root‐end surgery with biopsy was performed. One month later, the biopsy results revealed the lesion to be a carcinoma. The patient was immediately referred to a cancer centre, where a definitive diagnosis of adenoid cystic carcinoma was made. A prompt biopsy is critical for the definitive diagnosis of malignancies for timely treatment.