Enamel hyperplasia (enameloma): etiology, classification, diagnosis and treatment

Enameloma is a tooth developmental anomaly that manifests as a spherical, protruding enamel mass on the root surface of a permanent or primary tooth. It is also referred to as enamel hyperplasia, enamel drop, enamel pearl, or enamel nodule.

Epidemiology

Enamelomas are quite rare. The incidence of enamel pearls varies depending on the study method and population:

• generally, in individuals: 0.23 to 4.82%;
• particularly on molars (in targeted studies): 1.71 to 6.80%.

The highest incidence is observed in the permanent molars of the upper jaw.

Etiology

Disruption of odontogenesis processes is the primary cause of enamel hyperplasia. The formation of enameloma is associated with the local transformation of the remnants of the enamel epithelium of Hertwig’s root sheath into enameloblasts (enamel-producing cells). Consequently, an ectopic drop of enamel develops where the root cementum should be.

The effect of enameloma on the organs of the oral cavity

Enamel pearls prevent periodontal tissues from attaching to the root surface, create a niche for bacterial colonization and plaque retention, and make hygiene care difficult. If the enameloma is located in the area connecting with the oral cavity, it can provoke the rapid formation of a deep periodontal pocket and the development of local periodontitis. Enamelomas in the root furcation area of ​​primary teeth can cause late replacement of primary teeth and deviation of the eruption path of the secondary teeth.

Anatomy and classification

Macroscopically, enameloma appears as a round or hemispherical white formation with a smooth, shiny surface, tightly attached to the surface of the tooth root. Its size varies from 0.3 to 4.48 millimeters.

Histological classification

Location of enamel pearls

Most often, this abnormal finding is localized:

• mesially or distally on the neck of the tooth, close to cementoenamel junction;
• close to ​​the root furcation or to the groove between incompletely separated roots.

Also, in rare cases, enamelomas can be found on the tooth crown or in the coronal, middle, or apical third of the tooth root.

Most commonly, enamelomas occur in the furcation areas of maxillary molars, between the distobuccal and the palatal roots. Large enamel pearls most often develop on the lower molars and may contain pulp. Enamelomas of maxillary molars are smaller in size but there may be several of them on one tooth. The cases of bilateral development of multiple enamelomas on all maxillary molars have been documented.

On premolars, canines, and incisors, enamelomas are quite uncommon. Sometimes enamel pearls are found in combination with other pathological masses (fibrous epulis, etc.).

Clinical manifestations

An enamel pearl may be completely asymptomatic.

If an enameloma has caused the development of a periodontal pocket, the patient may complain of the following:

• swelling and bleeding of the gums around ​​one or more teeth;
• food stuck between teeth;
• pain when chewing;
• tooth root exposed;
• tooth loosening.

Clinically, a hemispherical, solid, white mass with a smooth surface on ​​the tooth neck or bifurcation can be detected. In the event of concomitant local periodontitis, the gums around the mass are swollen and hyperemic and bleed when probing, and the depth the periodontal probe is placed into the gingival sulcus is 4 mm or more.

Diagnosis

Enamelomas can be clinically diagnosed visually on examination, during gingival retraction, periodontal probing, or tooth extraction surgery.

The main diagnostic approach is radiological, using the following methods:

• intraoral (contact) X-ray;
• radiovisiography;
• dental panoramic radiography;
• cone-beam computerized tomography (CBCT).

Radiographic findings: the radiograph shows a clearly defined, hyperintense, rounded shadow in the projection of ​​the tooth neck, on the root surface, or in the furcation area of ​​the tooth root. If the pulp is part of the mass, a radiolucency area may be detected in the center of the mass.

Treatment of enamel hyperplasia

Enameloma requires treatment if it is located in an area accessible to oral microflora penetration and biofilm formation.

The mass is excised using a diamond bur, the surface is ground and polished, and remineralizing therapy is administered. The patient should also be motivated to maintain oral hygiene carefully.

Possible complications of the mass excision:

• tooth root caries;
• external resorption;
• pulpitis (if the enamel pearl contained vital pulp).