Ultrasound for the treatment of osteoradionecrosis

Prevention of osteoradionecrosis of the jaws by low-intensity ultrasound in the dog model

The prevention of osteoradionecrosis of the jaws (ORNJ) is very important because of the current absence of effective therapies for this disease. The aim of this study was to determine whether low-intensity ultrasound has a preventive effect on ORNJ. Sixty healthy adult dogs were divided randomly into three groups: group A (radiotherapy alone), group B (radiotherapy followed by low-intensity ultrasound treatment), and a control group. The development of ORNJ was assessed and the rate of occurrence of ORNJ was compared between groups A and B. Micro-computed tomography, haematoxylin-eosin staining, and immunofluorescence were used to evaluate the microstructure of the mandible and changes in microvascular density in all groups. All animals in group A and group B (ultrasound applied for 30 days) developed ORNJ. Alveolar bone density was 609.48±53.77HU in group A and 829.65±81.46HU in group B (P=0.008). The trabecular bone volume fraction, bone surface area/bone volume ratio, trabecular thickness, and trabecular number were all lower in group A than in group B (P=0.037, P=0.022, P=0.017, and P=0.034, respectively). Haematoxylin-eosin staining showed that the Haversian canals in the osteons had expanded significantly in group A, with collagen fibres losing their circular orientation; group B tended to show typical osteons. The microvascular density in group A was decreased. In conclusion, the use of low-intensity ultrasound in the dog appears not to prevent the incidence of ORNJ, however it does somewhat improve vascularity and bone quality at the microscopic level, which contribute to ORNJ healing.

Osteoradionecrosis of the jaws--a current overview--Part 2: dental management and therapeutic options for treatment

PURPOSE

The aim of this paper is to explore the current theories about pretreatment assessment and dental management of patients receiving head and neck radiotherapy, and the therapeutic options to treat osteoradionecrosis of the jaws, based on the literature review.

DISCUSSION

Osteoradionecrosis is one of the most serious oral complications of head and neck cancer treatment. Osteoradionecrosis is a severe delayed radiation-induced injury, characterized by bone tissue necrosis and failure to heal. Osteoradionecrosis either stabilizes or gradually worsens and is notoriously difficult to manage. Because most cases occur in patients who were dentulous in the mandible at tumor onset, proper dental management is the single most important factor in prevention.

CONCLUSIONS

Complete dental clearance before treatment is no longer necessary. Controversy exists regarding the management of osteoradionecrosis of the maxillofacial skeleton because of the variability of this condition. The treatment of osteoradionecrosis has included local wound care, antibiotic therapy, surgical procedures, and the administration of hyperbaric oxygenation. Recently, new methods of treatment were introduced, according to the new theory about its pathophysiology.