Regional Block Anaesthesia

Question 1

Inferior Alveolar nerve block -Halstead Technique

Answer 1

• Targets Inferior alveolar nerve
• Anaesthetises
• Teeth and bone on one side of mandible
• Soft tissues on buccal aspect anterior to mental foramen
• Soft tissues of lower lip
• Reflected and attached gingivae from premolar teeth to midline
• Lingual nerve-anterior two thirds of tongue
• Injection at pterygotemporal space on medial aspect of ramus(region of mandibular foramen)

Question 2

Halstead Technique procedure

Answer 2

• Long 35mm needle no narrower than 27 gauge used
• Patient mouth open wide
• Thumb on coronoid notch
• Index finger extraoral at height of posterior border of ramus
• Syringe passed across lower premolars
• Penetration of syringe between external oblique ridge and pterygomandibular raphae
• Height of penetration halfway between thumbnail
• Advance needle until bone contacted(25mm of needle insertion)
• Withdraw, aspirate and inject 1.5-2 ml of solution

Question 3

Length of Halstead Anaesthesia

Answer 3

• Teeth→ 45mins
• Soft tissues→ up to 3 hours

Question 4

Injection in parotid gland results in

Answer 4

-Facial nerve→ Hemifacial paresis

Question 5

Gow-gates technique

Answer 5

• More superior than Halstead technique(more branches of mandibular nerve affected)
• Anaesthetises inferior alveolar nerve, lingual, long buccal, mylohyoid and auriculotemporal nerves
• Mouth wide open
• Parallel plane between corner of mouth and intertragal notch used as guide
• Syringe passed along maxillary canine of opposite side and across palatal cusps of maxillary second molar on injected side
• When bone of condyle contacted, slight withdraw, aspiration and injection of 2ml solution
• More effective than Halstead approach

Question 6

Akinosi-Varizani Technique

Answer 6

• Anaesthetises inferior alveolar nerve, Lingual nerve, mylohyoid nerve and occasionally long buccal nerve
• Administered with patients mouth closed
• Long needle no narrower than 27 gauge used
• Syringe introduced intraorally at level of mucogingival junction of maxillary molars
• Syringe advanced to medial surface of ramus where insertion into occurs
• Hub of needle adjacent to distal surface of maxillary second molar→ Needle should be in correct place for injection
• Aspiration and injection of 2ml solution slowly

Question 7

Mental and incisive nerve block

Answer 7

-Anaesthetises

• teeth and jaws from premolars to anteriors
• Soft tissues of lower lip and chin to midline on one side
• First molar in some cases
• Usually intraoral but extraoral approach can be used
• Needle inserted at depth of buccal sulcus between premolar teeth at apices→ Targeting mental foramen
• 1.5ml solution injected and tissues massaged to encourage entry of solution into foramen

Question 8

Long buccal nerve block

Answer 8

• Anaesthetises the buccal gingivae and mucosa and part of the cheek in the mandibular molar region
• 0.5ml solution in region of coronoid notch of mandible

Question 9

Maxillary Nerve block

Answer 9

-Anaesthetises

• Teeth and bone of maxilla on one side
• Buccal and palatal mucosa
• Skin of lower lip, lower eyelid and lateral aspect of the nose
• Intraoral and extraoral approaches
• Intraoral methods-Tuberosity approach and greater palatine foramen approach

Question 10

Tuberosity approach

Answer 10

• Solution deposited high in buccal sulcus → distal surface of maxillary second molar
• Angle of 45 degrees to depth of 30.. mm
• 2 ml solution deposited

Question 11

Infraorbital nerve block targets

Answer 11

• Teeth and associated bone from second premolar to central incisor
• Adjacent gingivae of the teeth
• Mucosal and skin of one half of upper lip
• Part of skin of nose affected

Question 12

Infraorbital nerve block technique

Answer 12

• ION approached from either intraoral or extraoral sides
• Intraoral approach→ long needle into buccal sulcus(between premolar teeth)

→Advance towards infraorbital foramen(palpated extraorally)

→1-1.5ml solution deposited at 16mm following aspiration

Question 13

Greater palatine foramen approach

Answer 13

• Mouth wide open=> greater palatine foramen identified →depression medial to second maxillary molar) distal surface)
• Insertion into pterygopalatine fossa(via greater palatine foramen)
• Needle angle 45 degrees superiorly and posteriorly to depth of 30 mm
• 2 ml solution injected

Question 14

Nasopalatine nerve block

Answer 14

• Anaesthetises tissue of hard palate adjacent to incisor teeth
• 0.2-0.5 ml solution adjacent to incisive papilla

Question 15

Weisbrem technique

Answer 15

• Open mouth as wide as possible
• Syringe on opposite premolars
• Advanced to lateral edge of plica pterygomandibularis(pterygomandibular fold)
• Needle 0.5 cm below chewing surface of maxilllary third or second molar=>
• In absence of teeth 1.5 cm from alveolar crest
• Needle advanced to contact bone, withdrawn, aspiration and injection of 1.5ml
• On withdrawl, rest of solution deposited for lingual nerve
• Anesthesia after 5-7 minutes