Achint Garg1, Suraj Agarwal2, Shweta Agarwal3, Samta Mittal4, Parul Singh5
Migration of a tooth across the midline is called TRANSMIGRATION which is a rare anomaly. Nodine (1943)1 & Thoma (1952)2 observed this condition in pre-historic skulls & living patients respectively. Ando et al (1964)3 were the first to use the term „„transmigration”. Tarsitano (1971)4 et al defined transmigration as the phenomenon of an unerupted tooth crossing the midline. Javid (1985), 5 expanded the definition to include, more than half the tooth which had passed through the midline. Joshi (2001)6 felt that the tendency of a canine to cross the barrier of the midline suture is more important consideration than the distance travelled. Transmigration is mainly associated with impacted teeth. Though all permanent teeth may be impacted, yet mandibular and maxillary third molars, maxillary canines, maxillary and mandibular premolars, mandibular canines and maxillary central incisors are the teeth most frequently involved in the mentioned order. Maxillary canine impaction is a well-known dental anomaly and its incidence is in the range 0.8–2.8%. 7 Mandibular canine impaction is less frequent. It is observed that transmigration involves almost exclusively mandibular and maxillary canines. Literature reports transmigration of mandibular canines are much higher than those of maxillary canines. 8 Of the reported cases of transmigration, the bilateral type of transmigration is even rare,very few cases have been reported so far.9 Mupparapu has proposed a classification for both unilaterally and bilaterally transmigrating mandibular canines.(Figure 1 & 2) Documented cases of bilateral canine transmigration and the patterns of transmigration were studied in depth for this report, and 3 new cases are added.