Aneurysmal bone cysts (ABCs) of the mandible are rare lesions with variable characteristics, including radiographic, histological and etiopathogenic features, mainly affecting patients in the second decade of life. This report describes and discusses an interesting case of an asymptomatic 7-year-old girl diagnosed with an ABC on the left side of the jaw. The lesion was treated by percutaneous embolization with Histoacryl® injection with fluoroscopic guidance. This is the first report in the literature of the use of this fibrosing agent in the mandible. Treatment was considered successful because all teeth maintained pulp vitality, and there was no recurrence for 3 years. Therefore, percutaneous embolization with Histoacryl® injection should be considered a safe, viable, and effective procedure for the treatment of ABCs in the jaw, replacing, in some cases, surgical therapy, and thus, being an important tool in the management of pediatric patients.
This is the first report of the use of Histoacryl® in ABCs in the jaw.
Percutaneous embolization may replace surgical therapy in some cases.
Percutaneous embolization is well accepted by pediatric patients.
Early diagnosis can be a critical factor in successful treatment.
Dentists should be always aware to clinical conditions and radiographic images.
Aneurysmal bone cyst (ABC) is a type of osseous lesion characterized by a benign pseudocyst with fibrous connective tissue stroma and large spaces filled with blood and no endothelial lining [ ].
ABCs predominantly affect patients in the second decade of life [ ], as about 80% of cases occur before age 20 [ ], mainly between 10 and 20 years of age [ ], being 13 years the median age of patients reported by many studies [ , , ]. They can occur in all skeletal bones, but they are more common in the long bones, with prevalence of only 2% in the jaws [ ].
There is no consensus in the literature regarding the best therapeutic method for treating ABCs. The most commonly used treatment methods are resection, curettage, embolization and intracystic injections. The choice of treatment method varies greatly, especially in children [ ]. But, despite of the method chosen, the goal is always the success of the treatment, which consists of complete reossification, with new bone formation with normal volume and mineralization characteristics [ , ], and without recurrence of the cystic lesion [ ]. Thus, the aim of this study was to describe a case of a 7-year-old female patient who developed an ABC on the left side of the posterior mandible and whose treatment was performed by percutaneous embolization with Histoacryl® injection.
Presentation of case
A 7-year-old female in the mixed dentition stage sought orthodontic treatment with her parents who were unhappy about the appearance of her smile.
Intraoral examination revealed a Class II molar relationship with an anterior deep bite and atresic dental arches ( Fig. 1 A).
An initial panoramic radiograph ( Fig. 1 B) showed normal condition of both dental and bone structures. Therefore, informed consent was obtained from the mother of the patient and orthodontic treatment was conducted as planned; slow expansion was performed in both arches with removable expander appliances.
The patient presented for orthodontic appointments each month and in the last month, it was possible to observe an unexpected posterior disclusion only on the right side, after 11 months of treatment ( Fig. 2 A). A panoramic radiograph control was requested to evaluate possible causes for such disclusion. Surprisingly, the panoramic radiograph revealed a unilocular radiolucent lesion involving the left posterior mandible ( Fig. 2 B). Although it did not cause any root resorption, it caused a displacement of all permanent teeth adjacent to the lesion. There was a slight inferior cortical expansion, but it was not clinically detectable.
An axial computed tomography was conducted and showed the presence of unilocular bone rarefaction with defined contours at the left posterior mandibular area, expansion of the buccal and lingual cortical bone and displacement of the basal and lingual surfaces ( Fig. 3 ).
Anamnesis excluded important medical or trauma history. Therefore, she was referred to an endovascular surgeon. Once again, informed consent was obtained from the mother of the patient and the treatment was immediately initiated.
A biopsy was conducted, a cytobacteriologic study was performed and the ABC was diagnosed. The endovascular surgeon performed a direct puncture of the aneurysmal bone cyst and a detection procedure of the intracystic septa. The verification of the absence of venous opacification and the measurement of the lesion volume were conducted using a Visipaque contrast material injection. Then, contrast material was aspirated, and the cystic area was washed with 0.9% saline. A combination of n-butyl-2-cyanoacrylate (Histoacryl®; B. Braun, Melsungen, Germany) and lipiodol, in 1:1 ratio, was injected with fluoroscopic guidance under general anesthesia ( Fig. 4 ).