Talon Cup – Developmental Anomalies in theShape of Tooth Crown and Its Relation to Tooth Eruption

Overview

Talon cusp, or the „talon-like small bump“, is a rare anomaly in the shape of toothcrown,which affected frontal teeth in maxilla and mandible. There is a superfluous smallbump,most frequently on the oral surface of the tooth,which extends from the cement-enamel junctionin direction to the incisor edge. The authors followed the occurrence and complications of thisanomaly in patients treated by orthodontics. There were 698 patients under treatment, whowere admitted to orthodontic treatment during 1998–2003. Talon cusp was noted in fourpatients prevalence was 0.57%. In three cases the permanent lateral incisor was affected, inone case it was the upper permanent middle incisor. In the first case the talon cusp was theplace of premature contact and followed to periodontal irritation of the affected tooth. In thesecond case it caused a delayed eruption of teeth into an anomalous position. In the third caseof an adult female patient the talon cusp was partially abraded and no problems were thereforecaused. In the fourth male patient, where the eruption of the affected lateral incisor into oralcavity was delayed, the talon cusp was diagnosed on X-ray picture as a suspected superfluoustooth or another eruption obstacle. The diagnosis of talon cusp was established during surgicalintervention, which clarified spatial conditions in the frontal area of upper dental arch. Due tothe squeezing the talon cusp was wedged into the middle incisor and temporary canine withnot yet resorbed root. The temporary canine was extracted in order to enable spontaneouseruption of the affected incisor. The authors discuss the appearance of the talon cusp on X-raypicture and a possibility to confuse it for a superfluous shape in not yet erupted teeth. They also indicate that this shape anomaly causes a delayed eruption of the affected tooth, often intoan abnormal position.

Key words:
talon cusp – developmental anomaly of tooth shape – obstacle to eruption – tootheruption