DENS IN DENTE ( DENS INVAGINATUS )

The dens invaginatus also called dens in dente, dilated composed odontoma or gestant odontoma, is a developmental disturbance resulting from invagination of the enamel organ toward the dental papilla before mineralization; it may be limited to the tooth crown or invade the root to affect the periapical region

Etiology: (i) delayed focal growth, (ii) stimulation in the area of the tooth bud and (iii) abnormal pressure on tissues surrounding the dental organ. The incidence ranges from 0.04% to 10% . Clinically, the crown of an affected tooth may appear normal or may have some alterations.

Oehlers classification:

Type I, characterized by a small invagination limited to the crown not extending beyond the cementoenamel junction;

Type II, the line delineating enamel invagination invades the root, yet is limited to it as a ‘cul-de-sac’ configuration, without reaching the periodontal ligament, yet it may communicate with the tooth pulp .

Type III, a severe form of invagination extending through the root and ending at the apical region without direct communication with the tooth pulp.

Radiographically, the roots present smaller dimensions with presence of a radiopaque formation with density similar to that of enamel, which is invaginated from the cusp through variable extents into the root. This invagination varies in shape and size, and may present a loop-like or pear-shaped configuration or a slightly radiolucent structure,  simulating a ‘tooth within a tooth’ .

                                                           REF: IEJ, 40, 146–155, 2007