Middle Superior Alveolar Nerve Block

1. Middle Superior Alveolar Nerve Block Nerve Anesthetized : Middle Superior Alveolar Nerve - Maxillary premolars and buccal tissues

2. Areas Anesthetized Pulpal anesthesia of first & second premolars and mesiobuccal root of first molar Buccal soft tissues and bone over same teeth

4. Indications Anesthesia of maxillary premolars only Infraorbital nerve block failure

5. Contraindications Infection /inflammation in area of injection

6. Advantage Minimized number of injections Minimized volume of solution

7. Disadvantage MSA nerve is only present 28% of the time

8. Alternatives Local infiltration (supraperiosteal) Periodontal ligament injection (PDL) Infraorbital nerve block

9. Landmarks / Area of Insertion Mucobuccal fold above second premolar Apex of second premolar

10. Signs and Symptoms Numb upper lip Pain free dental therapy

11. Safety Features Anatomically safe (no signifcant structures) Relatively avascular area positive aspirations - negligible (< 3%) Complications are rare

12. Technique - MSA Apply topical Position patient and identify landmarks Insert needle 5-10 mm Aspirate Inject 0.9 ml of solution, slowly

15. Failures of Anesthesia Needle inserted too high, or not high enough Deposition of solution too far laterally

16. Infraorbital Nerve Block

17. Nerves Anesthetized Anterior Superior Alveolar Nerve Middle Superior Alveolar Nerve Superior Labial Nerve also Inferior Palpebral Nerve Lateral Nasal Nerve

22. Areas Anesthetized Pulpal anesthesia of maxillary anterior teeth Pulpal anesthesia of premolars and mesiobuccal root of first molar Buccal soft tissue and bone of same teeth Lower eyelid, lateral nose, and upper lip

24. Indications Anesthesia of more than two maxillary teeth Supraperiosteal injections ineffective Inflammation/infection contraindicating local infiltration

25. Contraindications Discrete treatment areas (1-2 teeth only) Hemostasis Bleeding problems (eg. hemophelia, etc..)

26. Landmarks Mucobuccal fold above first premolar Infraorbital notch Infraorbital foramen

27. Area of Insertion Mucobuccal fold above first premolar Target area Infraorbital foramen Neurovascular bundle

30. Advantages Comparatively simple, safe technique Minimized volume of solution Minimized number of needle punctures

31. Disadvantages Psychological Administrator- fear of eye involvement Patient- apprehension of extraoral approach Anatomical Difficulty defining landmarks

32. Alternatives Supraperiosteal injection for each tooth Maxillary nerve block

33. Signs and Symptoms Tingling and numbness of lower eyelid, side of nose, and upper lip Numbness in teeth and soft tissues No pain during dental therapy

34. Safety Features Needle contacting bone Finger over infraorbital foramen

35. Technique Apply topical Position patient and identify landmarks Insert needle to upper rim of infraorbital foramen Aspirate Inject 0.9 ml of solution, slowly

38. Failures of Anesthesia Bone contact below infraorbital foramen Needle deviates laterally or medially

39. Complications Hematoma (rare) Positive aspirations - 0.7 %