The document discusses the middle superior alveolar nerve block technique. It provides anesthesia to the maxillary premolars and buccal tissues by blocking the middle superior alveolar nerve. The technique involves inserting the needle 5-10mm above the apex of the second premolar and injecting 0.9ml of solution. Complications are rare for this anatomically safe technique. Alternatively, an infraorbital nerve block can be used to anesthetize a larger area that includes the maxillary anterior teeth. This technique involves inserting the needle to the upper rim of the infraorbital foramen and has a low rate of complications.

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 %