Fusion of a maxillary third molar with a supernumerary fourth molar: A case report.

KEY CLINICAL MESSAGE: Dental fusion should be included in differential diagnosis when panoramic radiograph reveals changes in tooth shape or size. The use of specialized dental photographic techniques can augment the dentists' knowledge and awareness of such conditions.

ABSTRACT: Dental fusion of impacted teeth may show up as a change in tooth shape and size on the first radiographic examination. This report presents an impacted maxillary third molar fused with a peg-like distomolar in a 20-year-old male. The patient presented with symptoms of localized periodontitis distal to the second molar, and radiographic examination revealed abnormal dental structure of the third molar. Surgical extraction of the impacted molar was the treatment of choice. The final diagnosis of fusion was based on data from ex vivo CBCT, photographs of the extracted tooth, and extracted tooth's sections using polarizing filters. Two-dimensional radiographs may conceal special dental anatomies. Visualization of such cases using CBCT and dental photography serves to educate dentists and reduce postoperative complications. Knowledge and awareness of possible dental abnormalities are of utmost importance for successful treatment planning.