Most DBI lesions are discovered incidentally during routine radiographic examination. The size of the lesions is usually stable, with rare reports discussing potential for enlargement (Greenspan and Stadalnik 1995; Petrikowski and Peters 1997; Mariani et al. 2008). Nakano et al. in 2002 found a 7% increase in size of a DBI on a 10-year-old girl. This is in agreement with Petrikowski and Peters’ conclusion for children and teenagers that about 40% of DBIs are thought to increase in size a period of 10 years and about 17% decrease in size for the same period. It is thought that this increase in size accompanies normal bone growth. In our case series, we found no size changes during our follow-up times. In the absence of agreed guidelines, the authors suggest adoption other authors’ advice that the lesion is monitored at least until the patient’s growth is completed and the lesion has stopped evolving (Nakano et al. 2002).
Although DBIs are often of no clinical significance, dental extraction of a tooth embedded into a DBI may result in an infected socket and pain of the edentulous area (Marmary and Kutiner 1986). In this case series, however, none of these findings was noted as no extractions were undertaken in close proximity to a DBI. We found one case report of an implant placed in close proximity to a dense bone island. The authors resourced to CBCT imaging and advised extreme care in planning as well as increased period of follow-up post operatively (Li et al. 2016).
Two case reports found symptoms related to dense bone islands present in the femur and in the tibia of a 10 and a 69-year-old, respectively. In these cases, DBIs were managed with excision followed by histology (Greenspan et al. 1991; Diab et al. 2014). One paper report on neuropathy related with compression of the inferior dental nerve due to the presence of a DBI (Debevc et al. 2017). Although none of our patients reported any DBI-related symptoms, the authors recommend timely diagnosis and accurate treatment planning for DBIs.
Medically, DBIs are of little clinical significance; however, a differential diagnosis should be established to rule out osteoblastic metastases from a known primary tumor (Nakano et al. 2002). Although DBIs are histologically different to osteomas, it is important to consider these as differential diagnoses as these may be associated with adenomatous intestinal polyps which may suffer malignant transformations (Butler et al. 2005, Sinnott and Hodges 2020). Multiple DBIs, with or without associated osteomas, may be a feature of Gardner’s syndrome (Davies 1970). Suspected medical findings must be discussed with the patient’s medical practitioner.
This case series reports sixteen cases of DBIs. All cases required multidisciplinary management, with radiology assessment and reporting for diagnosis. Three patients had initiated or completed orthodontic treatment prior to diagnosis of DBI, two with no unfavorable outcomes to adjacent teeth. In other cases, caution was advised for orthodontic tooth movement in the proximity of the DBI. Liaison with orthodontic colleagues was undertaken in these cases. The remainder of patients required no further investigations or treatment, other than monitoring. However, one patient (case 10) was referred for an opinion mid-treatment, after root resorption had occurred. The presence of DBIs offers additional challenges for orthodontic treatment, including difficulty with achieving space closure and adequate root tip or torque (Sinnott and Hodges 2020). Due to these challenges, and the possibility of iatrogenic root resorption in relation to a DBI, care is recommended when planning orthodontic interventions.
Sinnott and Hodges (2020) suggest that CBCT may be beneficial to ascertain the full extent of the lesion. In this case report, a DBI seemingly measuring 6 mm on a periapical radiograph was found to be significantly larger (24 mm). In our case series, two patients were found to benefit from CBCT prior to orthodontic planning.
Following revision of the literature and findings from our case series, a management flowchart is proposed to aid in treatment planning of DBIs (Fig. 17). These findings include the need to monitor the lesion and request radiographic report when required. In addition, if orthodontic treatment or implant placement is required, care must be taken especially if the DBI is in close proximity to the roots or implant.