How does sickle cell anemia lead you to potential osteomyelitis of the jaws?

Bone infarcts: In sickle cell anemia, there may be bone death, or infarction, with a crisis. These infarctions render bones prone to infections, or osteomyelitis. These infections are most common in long bones, rather than the jaw, but may occur in any bone.

Lack of oxygen: Sickle cell disease can cause tissues to receive inadequate oxygen to survive, most frequently by these red blood cells blocking the blood flow (and hence oxygen) in small blood vessels supplying tissues. If tissue dies it is prone to become infected, and the bodies means of fighting infection is also compromised by the poor blood flow. Large joints are most common, but any tissue is at risk.