Enamel Pearl (enameloma)

A small nodule of enamel can form on the root surface near the amelocemental junction, particulary on maxillary molars; mandibular molars are the second most frequent site (Figure 1-1). This may result from cells of Hertwing’s sheath which have become differentiated into ameloblast. It consist of a circumscribed nodule of otherwise normal enamel, occasionally with a core of dentine and rarely containing a minute horn of pulp. Small lesions may become coated with cementum.


Figure 1.1 - Enamel Pearl on Buccal
of Lower Right Second Molar

Buccal Exostosis

Buccal exostosis ocurr as a bilateral row of bony hard nodules along the facial aspect of the maxillary (Figure 1-1) and/or mandible (Figure 1-2). They are usually asymtomatic, unless the thin overlying mucosa becomes ulcerated from trauma. One study reported that buccal exostoses were found in 1 of every 1000 adults, although the prevalence could be even higher. They ocurr equally in males and females.

Figure 1.1 - Maxillary Buccal Exostosis







Figure 1.1 - Mandible Buccal Exostosis









SHOVEL-SHAPED INCISORS

 This alteration occurs predominantly in Asians, with a prevalence of approximately 15% in whites but close to 100% in native Americans and Alaskans. Affected incisors demonstrate prominent lateral margins, creating a hollowed lingual surface that resembles the scoop of a shovel (figure 1-1). Typically, the thickened marginal ridges converge at the cingulum; not uncommonly there is a deep pit, fissure, or dens invaginatus at this junction. Maxillary lateral and central incisors most frequently are affected, with mandibular incisors and canines less commonly reported. Frequently, shovel-shaped incisors is seen in association with another variation of coronal anatomy, dens evaginatus.

Figure 1-1 Maxillary central incisors exhibiting prominent lateral margins.

   If shovel-shaped incisors are present, the affected teeth should be inspected for surface defects at the point where the marginal ridges converge. Any deep fissures or invaginations should be restored shortly after eruption to prevent carious exposure of the adjacent pulp.