This document discusses various techniques for mandibular anesthesia. It begins by introducing the classical inferior alveolar nerve block and its limitations. Alternative techniques are then presented, including the indirect technique, Clarke and Holmes' method, Sargenti's method, the Gow-Gates technique, the Vazirani-Akinosi closed mouth block, lingual nerve anesthesia, and extra-oral approaches. Each technique is described in detail, outlining the relevant anatomy, indications, contraindications, advantages, disadvantages, and procedural steps. Common causes of failure are also reviewed, such as deposition of anesthetic in the wrong site due to anatomical variations or faulty technique.

1. TECHNIQUES OF MANDIBULAR
ANETHESIA
Presented by:
Dr Sagar Jangam

2. Introduction
• Commonest procedure in General practice
• Improvement in techniques
• Improvement in understanding anatomy
• Maxillary > Mandibular anesthesia
– Thicker cortical plates
– Varied anatomy
– Limited accessibility to Inf alv nerve
• Need for good anesthesia

3. Classical Inferior alveolar nerve block
High % failure
Additional infiltration

4. Areas anesthetized:
Classical Inferior alveolar nerve block

5. Indications
» Multiple procedures in one quadrant.
» Buccal soft tissue anesthesia (anterior to first molar).
» When lingual soft tissue anesthesia is required.
Classical Inferior alveolar nerve block
Contraindications
» Infection or acute inflammation
» Very young child or physically or mentally handicapped
adult or child.
Advantages
» One single injection
Disadvantages
» Wide area of anesthesia
» Rate of inadequate anesthesia (15 – 20%)
» Intra oral landmarks not consistently reliable
» Positive aspiration (10-15%).
» Lingual and lower lip anesthesia,
» Partial anesthesia - bifid inferior alveolar nerve and bifid
mandibular canals are present.

6. Anatomical landmarks:
– Mucobuccal fold.
– Anterior border of ramus of the mandible.
– External oblique ridge
– Retromolar triangle.
– Internal oblique ridge.
– Pterygomandibular ligament
– Buccal sucking pad
– Pterygomandibular space.
Needle pathway during insertion
Approximating structures when needle is
in position :

7. Classical Inferior alveolar nerve block
Technique: 3 parameters to be considered:
Height of injection
Antero-posterior Site Of Injection
Penetration Depth
Patient seated
comfortably with
mandible parallel to
floor

8. Classical Inferior alveolar nerve block

9. PRECAUTIONS:
• Do not deposit LA if bone is not contacted.
• Avoid pain by not contacting bone too forcefully
FAILURES OF ANESTHESIA:
• Deposition of anesthetic solution too low
• Deposition of anesthesia too far anteriorly
• Accessory innervations to the mandibular teeth
• Bifid inferior alveolar nerve
• Incomplete anesthesia of the central or lateral incisors
Complications:
Hematoma
Trismus
Transient facial palsy
Classical Inferior alveolar nerve block

10. Alternative techniques
Indirect Method
The technique
• Needle used is a minimum gauge of 25
• Midline of the fingernail again indicates the point of insertion of the needle,
this being 1 cm above the occlusal plane
• Finger is placed on the external oblique ridge, as opposed to the retromolar
fossa with the direct method, it almost immediately strikes bone.
• The barrel of the syringe is now moved to the right until it is parallel with the
right lower molars.
• A few drops of analgesic solution are deposited and about 10 secs allowed
to elapse prior to inserting the needle approximately 7mm, thus passing it on
the medial aspect of the internal oblique ridge.
• The syringe is now swung back to the left side of mouth the barrel being
replaced over the lower premolars.
• The needle reaches the pterygomandibular space and strikes bone, avoid
injecting subperiosteally, prior to slowly depositing approximately 1.5 ml of
the solution.
• If the lingual nerve is to be blocked

11. METHOD OF CLARKE AND HOLMES (1959)
LA deposited at a higher level than the usual.
• The reasoning behind this is that when the standard direct or indirect
technique is employed the analgesic is placed immediately behind
the mandibular foramen which is approximately 1 cm above the
occlusal plane of the molar teeth.
• At this level the anterior part of the nerve is concealed by the lingual
and the sphenomandibular ligament and so local analgesic solution
may have some difficulty in diffusing to the well protected anterior
fibres. It is also likely that branches are sometimes given off from the
inferior dental nerve a little before it reaches the inferior dental
foramen, these fibres entering the bone by separate foramina
around and above the main one.
• By depositing the solution at higher level it reaches the nerve in a
position where it is not protected and before it has given off any
branches.

12. TECHNIQUE:
• Modification of indirect method.
• The patient in instructed to keep the mouth wide open and head-rest
is adjusted so that the lower occlusal plane is parallel to the floor.
• Assuming that a right inferior dental nerve block is to be
administered, the index finger is slid along the occlusal surfaces of
the molar teeth and the external oblique ridge is palpated.
• The finger is then rotated inwards so that the tip lies in the
retromolar fossa and the finger nail overlies the internal oblique
ridge.
• A syringe equipped with a long needle is advanced from premolars
on the opposite side, above the finger nail of index finger and not at
the midpoint as with the standard indirect technique.
• The needle is inserted for a short distance until bone is encountered.
The body of the syringe is then gently swung round until it lies over
the lower central incisors, keeping it parallel to the molar teeth in a
horizontal plane at the same time.
• The needle is passed another 2 cm deeper into the tissues and after
this 1.5ml of solution is slowly deposited.
METHOD OF CLARKE AND HOLMES (1959)

13. TECHNIQUE OF ANGELO SARGENTI (1966)
Modification of direct method
• Principal difference is that the nerve is approached from
a higher level than usual.
• A syringe with a 15/8 in (42 mm) 26 gauge needle is
used.
• The index finger is placed in the retromolar fossa with
the nail facing lingually.
• The point of the needle is then inserted opposite the
midpoint of the finger nail and a little beyond its tip.
• The barrel of the syringe is now placed between and in
contact with the upper premolars of the opposite side
and it is kept in this position whilst the needle is slowly
inserted in a downwards and backwards direction until it
touches bone, which is usually at a depth of 1cm

14. MANDIBULAR NERVE BLOCK
THE GOW-GATES TECHNIQUE – 1973
Introduction:
•George gow-gates, an Australian dental practitioner
•High success rate
•True mandibular nerve block

15. Advantages over inferior alveolar nerve block
• Its higher success rate.
• Lower incidence of positive aspiration.
• Absence of problems with accessory sensory innervation to
mandibular teeth.
Indications
• Multiple procedures on mandibular teeth.
• When buccal soft tissue anesthesia from the third molar to the
midline is required.
• When lingual soft tissue anesthesia is required.
• When a conventional inferior ANB is unsuccessful.
Contraindications:
• Infection or acute inflammation.
• Patients who might bite either their lip or their tongue, such as young
children and physically or mentally handicapped adults.
• Patients who are unable to open their mouth wide.
THE GOW-GATES TECHNIQUE – 1973

16. Advantages :
• Accessory innervation has been blocked.
• High success rate > 95% with experience
• Minimum aspiration rate.
• Few post injection complication Eg. Trismus.
• Provides successful anesthesia where a bifid inferior alveolar nerve
and mandibular canals are present.
Disadvantages :
• Lingual and lower lip anesthesia is uncomfortable for many patients
and possibly dangerous for certain individuals.
• The time of onset of anesthesia is longer (5min) than with an IANB
(3-5 min) primarily because of the size of the nerve trunk being
anesthetized and distance of the nerve trunk from the deposition
site.
• There is a learning curve with Gow-gates technique.
• Positive aspiration 2%
THE GOW-GATES TECHNIQUE – 1973

17. Nerves anesthetized (7)
Areas anesthetized:
THE GOW-GATES TECHNIQUE – 1973

18. TECHNIQUE:
THE GOW-GATES TECHNIQUE – 1973
LANDMARKS:
a. Extra-oral
Lower border of tragus (intertragic notch)
Corner of the mouth.
b. Intra oral
Mesiopalatal cusp of maxillary second
molar
Penetration of the soft tissue just distal to
the maxillary second molar at the
height established in the preceding
step.

19. THE GOW-GATES TECHNIQUE – 1973
TECHNIQUE:

20. THE GOW-GATES TECHNIQUE – 1973

21. VAZIRANI – AKINOSI CLOSED
MOUTH MANDIBULAR BLOCK
.
In 1977 Dr. Joseph Akinosi reported a closed mouth
approach to mandibular anesthesia
Indications:
•Limited mandibular opening (Trismus)
NERVES ANESTHETIZED (5)

22. LAND MARKS
• Occlusal plane of occluding teeth.
• Mucogingival junction of the maxillary molar teeth.
• Maxillary tuberosity
• Coronoid notch on the mandibular ramus.
Approximating structures when needle is in position
• a. Superior to the following
• Inferior alveolar vessels & nerve
• Insertion of internal (medial) pterygoid muscle.
• Lingual nerve
• Buccinator nerve
• Mylohyoid vessels & nerve.
• b. Anterior to deep part of parotid gland
• c. Medial to inner surface of ramus.
• d. Lateral to the following
- Medial (internal) pterygoid muscle.
- Sphenomandibular ligament.
VAZIRANI – AKINOSI CLOSED
MOUTH MANDIBULAR BLOCK
.

23. VAZIRANI – AKINOSI CLOSED
MOUTH MANDIBULAR BLOCK
.

24. TECHNIQUE FOR CLOSED-MOUTH APPROACH:
• With the patient seated comfortably in the dental chair, the operator
stands to the patients right side and slightly to the front.
• The patient is instructed to occlude the teeth.
• The operator retracts the patient’s lips exposing the maxillary and
mandibular teeth on the right side.
• The syringe with 15/8 inch, 25 gauge needle attached is aligned
parallel to the occlusal and sagittal planes but positioned at the level
of mucogingival junction of the maxillary molars.
• The needle penetrates the mucosa just medial to the ramus and is
inserted approximately 1½ inches.
• Following negative aspiration, the contents of dental cartridge are
slowly deposited.
• Care must be taken to ensure that the needle is inserted as closely
as possible to the medial surface of ramus. Allowing the needle to
be advanced too far medially is likely to result in the deposition of
the solution on the medial side of pterygomandibular space and
sphenomandibular ligament resulting in inadequate anesthesia or an
unsuccessful nerve block.
VAZIRANI – AKINOSI CLOSED
MOUTH MANDIBULAR BLOCK
.

25. VAZIRANI – AKINOSI CLOSED
MOUTH MANDIBULAR BLOCK
.

26. Advantages over classical IANB:
• First, the landmarks are easily identified, and the technique is
simple to master.
• Second, the three major nerves innervating the mandible may
be anesthetized with one needle insertion.
• Third, many apprehensive patients feel less threatened
psychologically when anesthesia is administered by this
method.
Disadvantages:
• Since the technique relies on a minimum of bony landmarks
for its execution, one is likely to be less successful with this
method.
• The depth of needle insertion, is a nebulous factor and results
in failure.
• In addition, improper angulation in a superior direction may
result in partial / complete anesthesia of the maxilla.
VAZIRANI – AKINOSI CLOSED
MOUTH MANDIBULAR BLOCK
.

27. LINGUAL NERVE ANESTHESIA
Can be achieved by 3 methods
1. By blocking the lingual nerve at the same
time as an intraoral inferior dental
injection
2. The submucosal infiltration of 0.5ml of
anesthetic a few mm below and behind
the region of the lower third molar on its
lingual aspect.
3. The infiltration of LA solution immediately
lingual to the gingival of mucosa to be
treated.

28. BUCCAL NERVE BLOCK

29. BUCCAL NERVE BLOCK

30. BUCCAL NERVE BLOCK

31. Incisive & Mental Nerve Block

32. Incisive & Mental Nerve Block

33. Incisive & Mental Nerve Block

34. Extra-oral Techniques
The aim of this technique is to achieve analgesia of the nerve after it
emerges from foramen ovale.
Nerve anesthetized:
Area anesthetized:.
Anatomical landmarks:
Mandibular nerve block

35. Indication:
• when it is desirable to anesthetize the
entire mandibular nerve and its
subdivisions with on needle insertion and
a minimum of anesthetic solution.
• When infection or trauma makes
anesthesia of nerves difficult or
impossible.
• Diagnostic or therapeutic purposes.
Extra-oral Techniques
Mandibular nerve block

36. Technique:
• The point of maximum concavity in the lower border of zygomatic
process is located by palpation and this point marked on the skin.
• The area is cleansed, and techniques practiced under thorough
aseptic condition. Local analgesia of the area is obtained with
infiltration injection using a fine needle.
• A 21 guage 31/8 inch (8 cm) needle, marked to a depth of 4 cm with
rubber marker is now inserted at right angles to the sagittal or
vertical axis of the patient and also at right angles to the skin.
• The needle is slowly inserted until the lateral pterygoid plate is
reached, which is at a depth of approximately 4cm.
• The needle is now withdrawn and reinserted a few degrees further
distally so as to pass just behind the posterior border of lateral
pteygoid plate.
• If this is achieved, it will be possible to insert the needle to a greater
depth.
• However the needle should not be inserted more than 4mm beyond
the established depth of lateral pterygoid plate and on no account to
more than a total depth of 5cm.
• Now 2ml of solution is injected and this should produce analgesia of
the mandibular teeth, the side of tongue, the lower lip, the skin of the
cheek, innervated by long buccal nerve and the skin overlying the
temple.
Extra-oral Techniques

37. MENTAL AND INCISIVE NERVE BLOCK
(EXTRA ORAL APPROACH)
Extra-oral Techniques
NERVES ANESTHETIZED :
AREAS ANESTHETIZED :
TECHNIQUE:
supraorbital, infraorbital notch
palpate extraorally
25 guage 1 inch needle
30 degree downwards, 45 degree forwards

38. KURT THOMA TECHNIQUE
Extra-oral Techniques
Technique:
•First, the anterior border of masseter is located
•Then the operator’s finger is run down this border until its lowest point is found.
•This point is marked and a line is drawn connecting this with the tragus of the ear.
•The midpoint of this line is noted as it marks externally the position of mandibular
foramen.
•A line is drawn from this point parallel with the posterior border of mandible to the
lower border.
•This line is now measured and a 21 gauge needle of 7-8 cm length is marked to a
similar length by means of a piece of rubber stopper.
•After cleansing the skin, an infiltration injection is made in the area with a fine
gauge needle to obtain local analgesia.
•The long needle is now inserted on the inner aspect of the lower border of
mandible, care being taken to keep it as near as possible throughout the injection.
•The needle is gradually inserted, taking great care to keep it parallel with the line
marked on the skin of the external surface of the mandible.
•When it has reached the depth indicated by the marker i.e opposite point marked
on the skin overlying the position of the foramen, the LA solution is slowly injected.
Indication: Ankylosis of TMJ.

39. Computers in L.A. !!!
C
C
L
A
D

40. Computers in L.A. !!!
C
C
L
A
D

41. TECHNIQUE RELATED CAUSES OF
FAILURE OF MANDIBULAR NERVE BLOCK
• The most important factor is the deposition of the solution in the
wrong site which may be due to several causes.
• Insufficient knowledge of local anatomy of the region.
• Individual anatomical variations occurring in different patients,
especially those factors affecting the relative position of the
mandibular foramen.
• Variations due to age
- In children the mandibular foramen is relatively lower than in
adults.
- In the edentulous adult reduction in depth of the body of mandible
occurs due to resorption of alveolar bone.
• Faulty technique – with the inferior alveolar nerve block the
commonest errors are
– Injecting too far posteriorly because the barrel of syringe is not
far enough back over the opposite premolars.
– Injecting too low down. This is often because the lower lip is
allowed to lie between the barrel of the syringe and the teeth,
thus giving it a downward angulation.

42. Conclusion
Pertaining to the varied anatomy of the
pterygomandibular space the success rate of
the inferior alveolar nerve block is
considerably low, even with proper injection
technique of administering. Probably to
rectify this we need to develop better and
more intelligent CCLADs with integrated
RVGs to increase the success rate.

43. REFERENCES:
1. Local anesthesia - Roberts and Sowray.
2. Hand book of local anesthesia – Stanley F.
Malamed
3. Monheim’s local anesthesia and pain control in
dental practice – C. Richard Bennett.
4. Regional anesthesia of oral cavity – J. Theodore
Jastak and John A Yagiela.
5. Sedation, local anesthesia and general anesthesia
in dentistry – Neils Bjorn and Hayden.
6. Sicher’s Oral anatomy – Sicher & Dubrels
7. Management of Pain – John J. Bonica
8. Essential of Human Anatomy – A. K. Datta

44. Thank you