Bone

Radiation doses exceeding 60 Gy result in endothelial cell death, leading to obliterative endarteritis and periarteritis. Additionally, the bone’s ability to repair itself becomes compromised, causing osteoblast and osteocyte necrosis along with fibrosis of the periosteum and marrow spaces. Consequently, irradiated bone becomes hypocellular, hypovascular, and hypoxic, increasing the risk of osteoradionecrosis (Figure 11).¹³

Figure 11.

Figure 11.

Chronic radiodermatitis and ulceration and osteoradionecrosis of the mandible.

The impact of radiotherapy on a child’s developing bone depends on several factors, including the child’s age at the time of treatment, the quality and quantity of radiation administered, and the location and extent of the bone within the treatment field. Doses above 20 Gy may significantly impair bone growth, leading to maxillary and mandibular hypoplasia. Additionally, asymmetrical radiation exposure may result in hemifacial hypoplasia.¹³