Usefulness of CBCT for imaging of eruption disorders - case report

Tooth eruption disorders are a significant problem in clinical practice of a dental surgeon. They are observed in three forms: retention/impaction, primary and secondary retention. A retained tooth is by definition fully formed and after its physiological eruption time it still remains in the bone. Primary retention is the result of a genetic defect in the eruption mechanism (a mutation in the PTHR1 gene) and it is diagnosed before tooth eruption, with characteristic retention of distal teeth in relation to the first tooth that is affected. Secondary retention of eruption is caused by ankylosis.

Case report
The female patient, aged 15 years and 4 months, presented at the Outpatient Clinic of Maxillary Orthopaedics at the Dental Clinical Centre of the Medical University of Lublin. The radiological and intraoral examinations showed numerous tooth eruption disorders and hypodontia of the tooth 42. Treatment plan: A cone beam CT examination to determine the structure and location of retained teeth 13, 17 and the stage of reinclusion of the tooth 55. Scheduling a surgical procedure. Delaying orthodontic treatment – observation of eruption of teeth 13 and 17. Performing the radiological examination again, after 6 months, in order to assess the dimensions of the maxillary alveolar process near teeth 14 and 16.

Discussion
Eruption disorders are often associated with other dental abnormalities, and therefore additional examinations are required. Due to its slow and asymptomatic course, reinclusion often remains unnoticed. Its recognition in the early stages of the patient's development allows to avoid the occurrence of dentoalveolar complications.

Conclusions
CBCT in cases of eruption disorders of permanent teeth or reinclusion of deciduous teeth increases the likelihood of a correct diagnosis.