This is wonderful for the procedure itself but can be disastrous for someone with an one of the undiagnosed hypercoagulation disorders previously mentioned. Moreover, the poor outflow characteristic of osteonecrosis means that the vasoconstrictor can remain in the area much, much longer than the few minutes needed for profound local anesthesia. And to add injury to insult, literally, the reperfusion of the bone after the vasoconstrictor wears off releases large numbers of tissue-damaging oxyradicals. Normal tissues can withstand this onslaught nicely, but a nutrient-starved ischemic marrow is at risk. Additional risk factors for ischemic disease of the maxillofacial bones include the common practice of prescribing prednisone or prednisolone to prevent swelling after oral surgical procedures.
Corticosteroid use is the most common cause of non-traumatic osteonecrosis.
The inflammatory mediators at work in this chronic process are capable of increasing local and systemic coagulation.