Pre-eruptive diagnosis and management of occlusal dens evaginatus in premolar teeth

Dens evaginatus (DE) is a developmental dental anomaly that presents as an enamel protuberance commonly associated with the tooth's anatomical fossa.^1,2 This uncommon dental aberration may project superior to the neighbouring enamel tissue and histologically it is comprised of an external enamel shell, a dentine core and, occasionally, a pulp tissue horn. The pulp tissue may extend partially or entirely into the tubercle.³ DE most frequently arises from the occlusal fossa of posterior teeth and the palatal/lingual surface of anterior teeth. It is more commonly seen in premolars but it can present in molars and canines; its presentation being five times more common in the mandible than the maxilla.⁴ Typically, the anomaly will present bilaterally in a symmetrical fashion with a slight gender predilection for females.⁵ There is no evidence that the occurrence is related to any medical problems or syndromes. Indeed, the literature is awash with nomenclature that have been used to describe this morphological phenomenon, such as odontome, odontoma of the axial core type, evaginatus odontoma, occlusal enamel pearl, occlusal tubercle, tuberculum anomalus, accessory cusp, supernumerary cusp, interstitial cusp, tuberculated cusp, tuberculated premolar, Leong's premolar, dens evaginatus and talon cusp (in reference to the anterior teeth).^{5,6,7,8,9,10,11,12,13,14,15,16,17,18-19} Most of the literature is in agreement that the developmental processes that lead to the presentation of DE and talon cusp are very similar,^1,6,19,20 to the extent that the terminology ‘talon cusp’ has traditionally been used to describe DE. The latter, coined by Oehlers (1967), was later universally adopted to allow differentiation between the anterior and posterior tooth presentations.¹⁸ Other developmental oddities, such as the cusp of Carabelli, with a reported prevalence of 17.4 to 90%, typically seen on the palatal surface of the maxillary first molar mesiopalatal cusp, seem to be morphologically distinct. The differentiation is primarily histological, as the enamel process rarely contains pulpal tissue and only occasionally dentinal tissue. In addition, the position of Carabelli's cusp is inconsequential and would not normally present an occlusal interference, in contrast to DE or a talon cusp.¹