Odontomas are developmental tumors that arise from the dental tissue. They are benign and can be classified into compound and complex. Usually, they occur at a young age and are asymptomatic.
Odontomas are hamartomas that most frequently occur in children and young people, with a higher incidence in the second decade of life. They are not, however, limited to this age group. Odontomas in themselves are rare tumors, with cases comprising only 0.1% of the general population, but make up a large proportion of odontogenic tumors . In fact, they are the most common masses of odontogenic origin to occur in the oral cavity.
They consist of dental tissue that is both mesenchymal and epithelial in origin and may contain any of components of teeth, that is, pulp, dentin, enamel or cementum. It is unclear in the literature whether the tumors have a male or female predilection, however, some authors claim that odontomas have a marginal female preponderance .
Odontomas are usually small and asymptomatic, although generally, they can disrupt the eruption of neighboring teeth. Symptomatic odontomas typically present with displaced teeth, pain, swelling and a disruption of the bony architecture of the jaw . The latter is especially common with odontomas that present as a large mass, prone to complications such as bone expansion and impaction  . Patients may have other dental problems simultaneously.
Odontomas are often classified into two types: compound and complex. They can occur both in the maxilla or mandible, although the former is the more common location  . Compound odontomas are small, organized structures that resemble a cluster of teeth . They tend to occur in the anterior part of the maxilla. In contrast, complex odontomas are poorly differentiated structures that contain cementum, dentin, and enamel. These tend to develop in the posterior maxilla. Odontomas can occasionally occur in soft tissue (gums) .
There are a number of risk factors for the development of odontomas, and these include trauma, infections, inherited conditions like Gardner and Hermann's syndromes, genetic mutations, and the abnormal proliferation of a type of neural crest cells (odontoblasts) that are found in the pulp .
There are two standard methods of diagnosis of odontomas, and these include radiographic imaging, as well as histological analysis of the sample tissue. Often, odontomas are discovered incidentally, during routine radiographs  .
Typical radiographic features are dependent on the type and stage of a particular tumor. Initially, tumors may be radiolucent, with the inclusion of small calcifications. They progress to being entirely radiodense, with a persisting radiolucent rim. Compound odontomas may show denticles, which appear in different shapes and sizes and resemble teeth, within a well-demarcated, septate, radiolucent mass .
Complex odontomas have no recognizable structures and are a mixture of dense material within a lucent margin  . Dentigerous cysts may also be visualized, although their occurrence is rare.