Case #5 Diagnoses: Idiopathic Osteosclerosis (Dense Bone Islands)
Figure 10. Panoramic Image of a Dense Bone Island.
Demographics: Average age for Dense Bone Island (DBI) is twenties and thirties, with a 2:1 female predilection to males.
DBI is a form of idiopathic osteosclerosis, presented as an increased development of compact bone (enostoses) that extends from the inner surface of cortical bone into cancellous bone, with defined borders (Figure 10). DBI can occur in alveolar bone, as well as other skeletal regions such as the pelvic, long bones, and spine. They may be located at the apical regions of teeth, inter-radicular, or no regional attachment to dentition. The lesions do not appear to be associated with nonvital teeth, as it is with condensing osteitis. The etiology of DBI is unknown. Some studies speculate they are a result of a developmental resorption error during endochondral ossification. Radiographically they do not typically show bone expansion buccolingually or displace adjacent teeth or bony anatomic structures. However, in one study 9.7% of cases showed resorption of the first permanent molars.5,11-13
Clinical Notes: Individuals are typically asymptomatic. Radiographically osteosclerosis is commonly seen as a radiopaque lesion found in the mandibular premolar and molar regions, with the first molars being the most common teeth. The bone islands range from 2.5 to 7.0 cm.5,11
Differential Diagnoses: Condensing osteitis, hypercementosis, benign neoplasms.