13.5.2 Accessory cusps
Extra cusps are not uncommon in the human dentition and may occur in both the
primary and permanent dentition, most commonly affecting molar teeth. In the
primary dentition the most common accessory cusps are seen either on the
mesiobuccal aspects of the maxillary first molar or the mesiopalatal aspect of the
maxillary second molar, the latter being similar to the cusp of Carabelli seen on the
first permanent molar. The latter is a relatively frequent finding on the mesiopalatal
aspect of the crown of the maxillary first molars, is typically bilateral and may be seen
in 10-60% of various populations. Permanent incisor teeth may have an additional
cusp arising from the lingual cingulum, often referred to as a 'talon cusp'. This affects
the maxillary central incisor most commonly. Talon cusps may interfere with the
occlusion and may be aesthetically unpleasing. (811HFig. 13.15 (a) and (b)). As with
double teeth, caries may occur in the groove between the cusp and palatal surface of
the incisor. Other incisor evaginations have been reported. (812HFig. 13.16(a and b)).
Permanent canines may also have a prominent lingual cusp, perhaps indicating a
tendency towards a premolar tooth form. Additional cusps may uncommonly be seen
on premolars.
Treatment
The talon cusp may require action for both aesthetic and occlusal reasons. Selective
grinding, repeated over a period of time, will reduce the height of the cusp and allow
deposition of reactionary dentine on the pulpal surface of the dentine. Single visit
sectioning of the cusp from the tooth followed by elective pulpotomy can also be
considered.