Edema and hematoma after local anesthesia via posterior superior alveolar nerve block: a case report.

Although rare, complications can occur with anesthetic procedures. The posterior superior alveolar nerve (PSAN) block anesthetic technique has a high success rate, but positive aspiration can cause bruising, transient diplopia, blurred vision, and temporary blindness in approximately 3% cases. When edema occurs, it is occasionally massive, especially in the infratemporal fossa, and the resulting hematoma is usually unsightly.