Endodontic management of dens invaginatus Type IIIb: Case series.

Dens invaginatus may be seen as a developmental malformation. It is characterized by an invagination of the enamel and dentin, creating a lumen inside the affected tooth, which may extend as deep as the apical foramen. Oehlers Type IIIb is considered the most challenging clinical conditions. The purpose of this study is to discuss the nonsurgical endodontic management of vital and necrotic dens invaginatus Type IIIb cases. Due to the complex anatomical consideration of dens invaginatus Type IIIb, endodontic treatment is extremely technique sensitive. A conservative approach was used in a vital case to treat the invaginated lumen only, to preserve the vitality of the pulp, and a more invasive approach was used in a necrotic case to debride the lumen and necrotic pulp for proper disinfection of the root canal system. Although different, all the approaches were successful. The clinical signs and symptoms were resolved. The vital case remains vital after 19 months, and the recall radiographs were able to show satisfactory periapical healing both in vital and necrotic cases. Due to the highly complex anatomy of dens invaginatus Type IIIb, the decision of preserving the pulp vitality may not be related only to pulpal diagnosis but also to the technical requirements of the treatment. Although very technically sensitive, it may be possible to treat the invaginated lumen exclusively, while preserving the vitality of the pulp. Necrotic cases may require a more aggressive approach to achieve a favorable prognosis.