Question 8 of 20

Click on the correct answer to the following question:

If a hematoma appears after the posterior superior alveolar injection (PSA), it is most likely due to:

  1. anesthetic agent injected too quickly
  2. the lack of a vasoconstrictor in the anesthetic agent
  3. needle inserted too far posteriorly into the pterygoid plexus of veins
  4. a 25 gauge needle was used in place of a 27 gauge needle