Mandibular First Molar

Root Canal Anatomy Project 

Merging Science & Art

Realistic 3D model obtained by micro-CT technology and characterized by using advanced computer design techniques. Watch in HD!

Double Maxillary Molar

 

Root Canal Anatomy Project

Merging Science & Art

Realistic 3D model obtained by micro-CT technology and characterized by using advanced computer design techniques. Watch in HD!

Double Maxillary Molar Teeth

Conjoined teeth, a rare dental anomaly, have been described using various terms including gemination, fusion, double teeth, and twinning. Gemination refers to an attempted division of a single tooth germ, resulting in a tooth with a doubled crown and a single root. Fusion, on the other hand, occurs when two separate tooth germs fuse together, leading to a tooth with a larger crown and two distinct roots. In some cases, it can be challenging to distinguish between the two conditions, which is why some authors prefer to use the term "double teeth" for both. This condition usually affects anterior teeth, but it can also occur in premolars and permanent molars, albeit rarely. In 1963, Tannenbaum and Alling defined gemination as the formation of two teeth from a single follicle, with evidence of an attempt to keep them separate. Pindborg's definition of fusion involves the union of two or more separate developing teeth, which can result in either complete (total/true fusion) or incomplete (partial/late fusion) fusion, depending on the stage of tooth development. Overall, conjoined teeth can present diagnostic challenges, and proper identification and classification are important for appropriate management and treatment.

References

Pindborg JJ. Pathology of the dental hard tissues. Philadelphia: W.B. Saunders; 1970.

Tannenbaum KA, Alling EE. Anomalous tooth development: case report of gemination and twinning. Oral Surg Oral Med Oral Pathol. 1963;16:883-8.

Versiani, M.A., Martins, J.N. & Basrani, B. (2018). 3D visual glossary of terminology in root and root canal anatomy. In M. A. Versiani, B. Basrani & M. D. Sousa Neto (Eds.), The Root Canal Anatomy in Permanent Dentition (1 ed., pp. 391-422). Switzerland: Springer International Publishing.