LA in the Mandible Flashcards
What are the branches of V3
1) Undivided nerve
-medial pterygoid branch
-dura mater branch
2) Anterior division
-lateral pterygoid branch
-masseter muscle branch
-temporal muscle branch
-long buccal nerve
3) Posterior division
-auriculotemporal branch
-lingual nerve
-mylohyoid nerve
-inferior alveolar nerve
-mental nerve
-incisive nerve - terminal branches
What are the 4 major branches of V3
IAN
Lingual
Long buccal
Mental
What are the mandibular injections
1) Conventional mandibular block
2) Gow-gates mandibular block
3) Uni-linear madibular block
4) Vazirani-Akinosi mandibular block
5) Mental nerve block
6) Mylohyoid nerve block
What is the most challenging area of oro-face to anesthetize and why?
IAN b/c:
-structural complexity of the mandibular division (V3)
-entire division is freely moveable along with the mandibular structures which it innervates
-bone is more compact –> local infiltration of anesthetic is NOT effective
What does IAN provide sensation to?
-Mandibular teeth
-Body of the mandible, inferior portion of the ramus
-Buccal mucoperiosteum, muscus membrane anterior to the mental foramen
What is the path of the IAN
-Descends inferiorly and laterally across the pterygoid space
-Forms 2 branches = Lingual nerve (anteriorly) and Mylohyoid nerve (posteriorly)
-Enters into mandibular foramen
-Traverses beneath the roots of the mandibular teeth to the mental foramen
-Divides into: Mental nerve and Terminal IAN branches
*Terminal IAN branches can cross the midline - usually to opposite incisors but can extend to opposite mandibular foramen
What is the path of the lingual nerve
-Descends inferiorly and medially between the ramus and medial pterygoid muscle
-Runs anterior and slightly medial to the inferior alveolar nerve
-Runs just distal and medial to the third molar
-Extends inferiorly to the tongue
What does lingual nerve provide sensation to
-Anterior two-thirds of tongue
-Floor of the mouth
-Lingual gingiva
What is the path of the long buccal nerve
-Branches off anterior division of V3
-Descends parallel to the lingual nerve and IAN
-At retromolar pad, swings laterally and fans up and out over the area of the buccal mucosa
**Also known as the buccal nerve
What does the long buccal nerve provide sensation to?
-Buccal gingiva of molar/premolar area
-Skin of the cheek
-NO innervation of the lip
*Some overlap between terminal branches of Long buccal nerve and Mental nerve
What does the mandibular block anesthetize
Using 1 anesthetic carpule:
- IAN
- Lingual nerve
- long buccal nerve
What are the types of mandibular blocks
1) Conventional mandibular block
2) Uni-linear mandibular block
3) Gow-Gates mandibular block
4) Vazirani-Akinosi mandibular block
What are the target zones for the conventional mandibular block
There are two target zones:
-Posterior Zone: includes both the IAN and Lingual nerve
-Anterior Zone: includes the Long Buccal nerve and is targeted in a separate injection
What is the posterior target area in the conventional mandibular block and what is it defined by?
Posterior Target = Retromolar Triangle: Inferior alveolar nerve as it passes downward to the mandibular foramen but prior to entry into foramen
Defined By:
1) Pterygomandibular raphe medially
2) Anterior border of the ramus laterally
3) Hamular notch superiorly
*The target area is characterized by a dimple or depression found roughly in the center of the triangle
What are parameters to consider for conventional mandibular block
1) Height of injection (6-10mm above occlusal plane)
2) A-P placement of needle - 3/4 of the A-P distance from the coronoid notch back to deepest part of pterygomandibular raphe
3) Depth of penetration - until bone is contacted. ~20-25mm in depth or 2/3-3/4 depth of long needle
What needle is used for conventional mandibular block
25 long
Where do you insert needle in conventional mandibular block
Align barrel of syringe with contralateral premoalrs - parallel with occlusal plane
Insertion to about 2/3 to 3/4 length until bone in contacted
Facts for conventional mandibular block
-25 long needle is used
-Align barrel of syringe with contralateral premolars - parallel with occlusal plane
-Insertion is made about 2/3 - 3/4 needle length until bone is contacted
-Bevel is toward the bone
-Positive aspiration common
-After reaching the target –> slowly deposit the entire carpule except 0.2cc carpule
What is the posterior target zone in the conventional mandibular block
Defined by:
1) the deepest extent of the mesial concavity of the ascending ramus
2) the deepest extent of the posterior concavity of the ramus
What is present in the posterior target zone in conventional mandibular block
the lingula is present
What happens when the lingula is presenting a barrier in conventional mandibular block
Penetrate dimple then swing barrel of the syringe toward the midline in order to reach the posterior target area
What is the anterior target area of the long buccal nerve block
Anterior border of the ramus
What is the penetration for long buccal block
Penetration of the mucosa is made:
-distal and buccal to the most distal molar tooth in the arch
-needle parallel to occlusal plane but buccal to the teeth
-reposition needle if necessary (shallow tissue) = 45 degree angle/laterally
What needle is used for long buccal block
25 long
Technique for long buccal nerve block
-25 long needle is used
-Insertion is made until bone is contacted –> 1-4mm
-**Make sure bevel is buried
-Bevel is toward the bone
-Deposit 0.2cc
What is the target zone for Gow Gates mandibular block
Target zone is significantly superior to the target zone of the conventional block
What are stats about the technique of Gow Gates
-High success rate (requires experience)
-Longer onset of anesthesia
-Low aspiration rate
-Successful anesthesia with bifid IAN/bifid mandibular canals
What is the target area/penetration of Gow gates
Target area:
-Anteromedial side of condylar neck
Penetration of the mucosa:
-Needle placed just disal to the max 2nd molar at the height of the tip of the MLi cusp (3rd molar if present)
-Syringe barrel aligned with the imaginary line between intertragus notch (injection side) and the corner of the mouth (opposite side)
-make sure bone is contacted
-Sit pt upright for 5min with mouth open for 1-2min
What needle is used for Gow gates
25 long
Where is uni-linear block target zone
Approximately 1cm superior to the target zone for conventional mandibular block is an area where the IAN, the lingual nerve, and the long buccal nerve are closest together
—> running parallel
—> in close proximity
—> in a straight line
What is the target area/penetration of uni-linear mandibular block
Target area:
-1cm superior to conventional mandibular block target
Penetration of the mucosa:
-5mm above dimple of posterior triangle –> insert to 1/2 - 2/3 needle length
-swing barrel to opposite side –> advance until bone is contacted
-withdraw 2mm and deposit 3/4 carpule
-slowly withdraw, depositing remaining carpule (anesthesizes Li and Long Buccal)
Target area/penetration of Vazirani-Akinosi block
Target area:
-medial border of ramus
Penetration of the mucosa:
-Mouth is closed; light occlusion
-Syringe barrel is parallel to maxillary occlusal plane
-Needle is inserted at mucogingival junction of maxillary 2nd molar and advanced in a slightly lateral direction
*bone is NOT contacted
What needle used for Vazirani-Akinosi block
25 long
What is important in technique about Vazirani-Akinosi block
Bevel is AWAY from mandibular ramus - critical
Technique for Vazirani-Akinosi block
-25 long needle is used
-Insertion is made to about 3/4 needle length from the maxillary tuberosity
-Bevel is AWAY from the mandibular ramus
-Use a full carpule = 1.8cc
*sit pt upright
What are the mandibular accessory injections
Mental nerve block
Mylohyoid nerve block
Mental nerve block target area
Target area:
mental foramen, usually between apices of 1st and 2nd premolar
What needle for mental nerve block
25 long or 27 short
Technique for mental nerve block
-Insertion is made deep enough to bury the bevel of the needle
-Bevel is toward the bone
-Use 1/2 carpule
*apply pressure on the area that has “ballooned”
What is indication for mylohyoid nerve block
When a successful mandibular block has been given but pt still has sensation in some mandibular teeth (particularly molars)
What is the target area/penetration of the mylohyoid block
Target area:
-Lingual approach
-Just medial to mandibular 2nd molar
Penetration of the mucosa:
-Depth of the lingual vestibule
-45 degree angle to the long axis of the molar
What needle for mylohyoid nerve block
25 long or 27 short
Technique for mylohyoid nerve block
-Insertion is made to about 1/4 to 1/3 the needle length until bone is contacted (lingual border of body of mandible)
-Bevel is toward the bone
-Use 1/2 carpule
