Labial and palatal talon cusp on the maxillary supernumerary tooth in a deciduous dentition.

To cite: Bargale S, Sagari S, Purohit S, et al. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/bcr-2013202300 DESCRIPTION The occurrence of talon cusp in the deciduous dentition is very rare. Aetiology for the formation of the talon cusp is unknown. However, it may be due to the combination of genetic and environmental factors and hyperactivity of the dental lamina early in odontogenesis. A 7-year-old boy reported with a symptom of an abnormally appearing upper front tooth. His medical and family history was unremarkable. Parents reported the history of exfoliated primary right central incisor. Intraoral examination revealed the presence of an accessory cusp on the labial and palatal aspects of the primary maxillary right central incisor region, extending from cementoenamel junction towards the incisal edge on the labial and palatal aspects (figure 1). The supernumerary teeth with talon cusp on the labial and the palatal side were noted, resembling ‘X’-shaped appearance from the occlusal aspect (figure 2), mesiodistal and labiopalatal diameters were measured as 8.4 and 6.9 mm, respectively. There was no interference in the occlusion on closure of the jaw. An intraoral periapical radiograph revealed a ‘V’-shaped radio-opaque structure on maxillary