CBCT-Assisted Clinic and Radiographic Diagnosis of an Atypically Erupted Odontoma Associated With Supernumerary Tooth.

Odontomas are common benign odontogenic tumors and are typically asymptomatic, often detected incidentally through imaging exams. However, in some instances, these lesions may erupt into the oral cavity and coexist with supernumerary teeth, creating diagnostic and therapeutic challenges and interfering with normal tooth eruption. This case reports an unusual and complex presentation of an odontogenic lesion with clinic and radiographic features consistent with a partially erupted compound odontoma, associated with a supernumerary tooth and an embedded permanent lateral incisor. A 28-year-old female was referred to a dental school for evaluation of a recurrent, asymptomatic whitish spicule in the anterior mandibular gingiva. Initial radiographic examination revealed multiple radiopaque, denticle-like structures, in addition to a vertically oriented supernumerary tooth and an embedded left mandibular lateral incisor. Based on a two-dimensional imaging, a peripheral compound odontoma was initially suspected. Subsequent cone-beam computed tomography (CBCT) scan provided critical three-dimensional information, refining the imaging diagnosis and demonstrating an intraosseous compound odontoma with partial eruption into the oral cavity. Surgical removal of the embedded tooth was performed, while the supernumerary tooth and the odontogenic lesion, due to their lingual positioning and proximity to adjacent structures, were preserved. Later, the tooth erupted spontaneously, requiring a second intervention. Some residual denticles remained as a result of anatomical limitations. This case highlights the clinical, anatomical, and surgical complexity of erupted compound odontomas, underscores the indispensable role of CBCT in accurate radiographic diagnosis and treatment planning, and draws attention to potential challenges such as capsule rupture and incomplete removal of denticle-like structures remnants.