Dense bone island in mandible with 8 years of follow-up examinations

A case of dense bone island (DBI) in the mandible is presented. A 10-year-1-month-old (10Y1M) girl came to our clinic for dental caries treatment. Radiographic examinations incidentally found an isolated round mass with uniform radiopacity in the region below the mandibular left canine and first premolar, which was diagnosed as a DBI. The patient also had an anterior crossbite and was referred to an orthodontic specialist. Although the orthodontist anticipated that the DBI might cause some problems with tooth movement, there were no specific complications encountered and treatment was completed. Thereafter, periodical examinations were carried out for approximately 8 years from the first visit and there were no adverse condition seen in the affected area. Further, orthopantomographic examinations were conducted approximately every 3 years to monitor the size and radiodensity of the lesion. The lesion expanded by approximately 10% up to the age of 15Y2M, after which it was reduced in size at the age of 18Y3M to become approximately 10% smaller as compared to that at the first visit. Further, radiopacity increased from the first visit to the age of 12Y9M, and then was decreased at the ages of 15Y2M and 18Y3M.