A clinical case of jaw radionecrosis and periimplantitis after radiation therapy
Osteoradinecrosis (ORN) of the lower jaw is a serious complication that can occur in patients after a course of radiotherapy during the complex treatment of neoplasms of the head and neck. The predisposing factors in this case are the radiation dose, tumor localization, a history of dental injury and a compromised dental status.
Most often, it is in patients of the 50+ age category that neoplasms of the head and neck are recorded and, as a rule, most patients at this age have dental implants that play the role of supporting elements for orthopedic structures. The results of dental implantation, as well as the state of peri-implant tissues, are some constituent elements in the structure of the ethiopathophysiological process of jaw radionecrosis after radiation therapy.
Currently available studies are mostly focused on studying the prospects of dental implants installed before the therapeutic radiation procedure, or on determining the prognosis of such structures after such iatrogenic intervention. But the question of the effect of radiotherapy on a fully osseointegrated implant is still debatable and open, therefore this article is devoted to the description of changes in peri-implant structures after therapeutic irradiation using an example of a specific clinical case.
A 66-year-old patient was referred to our hospital for further treatment of ORN of the lower jaw. 7 years ago, he was installing titanium intraossal structures in place of the missing 35, 36, 45 and 47 teeth. Moreover, during a certain time, all installed implants were successfully osseointegrated, which was confirmed during numerical follow-up visits.
After a while, he was diagnosed with left-sided oropharyngeal carcinoma, the treatment of which was carried out by means of radiation therapy with a total dose of 70 Gy 2 years after the implantation intervention. During the analysis of medical documentation, it was found that the left jaw was included in the therapeutic radiation zone.
4 years after radiotherapy, the patient began to experience pain in the area of implants installed on the left side, in the same area he had significant inflammation and swelling of the gums. After the diagnosis of peri-implantitis, he was given conservative treatment consisting of local irrigation of the affected area and periodic use of antibiotics for 6 months. However, the symptoms of the lesion only intensified, and he was sent to our hospital for further treatment of the pathology.
During the clinical study, the patient showed painful swelling of the left cheek and hypesthesia of the lower lip on the left side, while the possibility of opening the mouth was limited to a width of one and a half fingers, and around the dental implants on the left side there was necrosis of the alveolar bone, inflammation of the mucosa and periodic purulence.
On the orthopantomogram, a weakly demarcation zone of bone tissue destruction in the area of implants at the site of 35 and 36 teeth was contoured, while the lesion reached the lower edge of the jaw, which provoked the appearance of a pathological fracture. There were no pathological lesions around the implants on the right side of the jaw (photo 2). Using a CT scan, it was possible to confirm the destruction of the lower jaw on the left and the presence of a fracture line through the entire thickness of the bone tissue.
CT images of the lower jaw on the left side: a) axial section in the region of the left first molar; b) coronal section in the region of the left first molar.
At the first stage of treatment, the patient underwent a course of 30 sessions of hyperbaric oxygen therapy, which allowed only slightly improve the existing symptoms of the lesion. Considering that no progression of the destruction area was observed in the X-ray photographs, a partial resection of the lower jaw area was carried out, followed by restoration of the defective area by means of a free microvascular flap from the fibula. The graft was fixed using a titanium plate.
a) Segmented resection of the affected area of the lower jaw; b) a localized bone graft from the fibula; c) resected lower jaw; d) orthopantomogram after surgery.