Dens invaginatus and treatment options based on a classification system: report of a type II invagination.

AIM: To give an overview of treatment options for dens invaginatus based on a classification system.
SUMMARY: Dens invaginatus is a dental malformation which may give endodontic complications. Treatment may vary in relation to anatomy, and a classification system for dens invaginatus forms the basis for discussion. A clinical case, classified as a type II invagination (Oehlers' classification), is also presented. Clinical and radiographic examination revealed an invagination penetrating into the apical third of the root canal in tooth number 12. The tooth was immature with an open apex, apical pathosis and a labial fistula. To control the infection, ultrasonic removal of the invagination was necessary, as the invagination prevented complete cleaning and shaping of the root canal. After chemo-mechanical preparation and dressing with calcium hydroxide, an apical plug of MTA was placed, followed by restoration of the tooth with resin-bonded composite. Healing of the lesion with hard tissue formation was confirmed at follow-up. KEY LEARNING POINTS * Knowledge about classification and anatomical variations of teeth with dens invaginatus is important in endodontic decision making. * A classification system may be helpful when treatment options are considered. * Classification of dens invaginatus requires a thorough preoperative radiographic examination.