Which injection technique carries the highest risk of hematoma?

Which injection technique carries the highest risk of hematoma?

• A. IANB
• B. PSA
• C. Infraorbital block
• D. Mental nerve block

Answer: (B)

Bleeding risk from injections in this region comes from how close the needle path is to large, nearby blood vessels and how much bony barrier shields them. The posterior superior alveolar block targets the PSA nerve as it courses near the pterygoid venous plexus and the posterior superior alveolar artery in the infratemporal area. That region is highly vascular and the vessels are numerous, with little solid protection once the needle slips a bit off course. If a vessel is pierced, blood can track into surrounding spaces such as the maxillary sinus or cheek, creating a hematoma. Because of this dense vascularity and relatively thin bony barriers at the maxillary tuberosity, this technique has the highest risk of hematoma among the options. In contrast, blocks performed closer to the mental foramen involve more superficial soft tissue with fewer large vessels, so hematoma is less likely. The infraorbital approach is near the infraorbital vessels but still carries a smaller hematoma risk than the PSA region. The inferior alveolar nerve block travels through the mandibular canal where bleeding can occur, but the surrounding vascular density and the route make sizable external hematomas less common than with the PSA block.

Bleeding risk from injections in this region comes from how close the needle path is to large, nearby blood vessels and how much bony barrier shields them. The posterior superior alveolar block targets the PSA nerve as it courses near the pterygoid venous plexus and the posterior superior alveolar artery in the infratemporal area. That region is highly vascular and the vessels are numerous, with little solid protection once the needle slips a bit off course. If a vessel is pierced, blood can track into surrounding spaces such as the maxillary sinus or cheek, creating a hematoma. Because of this dense vascularity and relatively thin bony barriers at the maxillary tuberosity, this technique has the highest risk of hematoma among the options.

In contrast, blocks performed closer to the mental foramen involve more superficial soft tissue with fewer large vessels, so hematoma is less likely. The infraorbital approach is near the infraorbital vessels but still carries a smaller hematoma risk than the PSA region. The inferior alveolar nerve block travels through the mandibular canal where bleeding can occur, but the surrounding vascular density and the route make sizable external hematomas less common than with the PSA block.