Osteoradioncecrosis Flashcards
osteoradionecrosis
exposed irradiated bone that fails to heal over a period of 3 months, excluding areas of residual or recurrent tumour
aetiology
ORN risk greatest:
- when radiation dose >60 Gy
- mandible>maxilla
- 7% irradiated pts
risk factors
radiation related factors
trauma and surgery (50% of ORN spontaneous)
pathogenesis
irradiated bone, periosteum, overlying soft tissue undergo inflammation and obliterative endarteritis
conditions ultimately lead to microvascular thrombosis, cellular death and progressive hypovascularity and fibrosis
radiated bed is hypocellular and devoid of fibroblasts, osteoblasts and undifferentiated osteocompetent cells
notani classification
I - ORN confined to alveolar bone
II - ORN limited to dentoalveolar bone or mandible above the inferior dental canal
III - ORN involving the mandible below the inferior dental canal, pathological fracture or skin fistula
how is this condition managed
local debridement
ultrasonic therapy
hyperbaric oxygen therapy
triple therapy
local debridement
removing necrotic bone leaves vital bone exposed –> vital bone is now exposed to inflammation leading to occluded blood vessels.
Ultrasonic therapy
Used is patients with exposed osteoradionecrosis
aims to improve blood supply to the area
performed in areas where there is no evidence of a residual tumour as UT could increase blood supply to it
Hyperbaric Oxygen Therapy
Oxygen delivered to an area
Increases partial pressure of oxygen which allows it to carry more plasma
Reduction in hypoxia and increase in angiogenesis
Triple Therapy
Chlorhexidine mouthwash 10ml (just keeps the area clean)
Doxycycline 100mg (good bony penetration)
Pentoxifylline 400mg (reduces inflammation)
Tocopherol 1000mg (antioxidant to combat free radicals)
Radiotherapy
Therapeutic radiation kills cancer cells and normal cells
