Mandibular nerve blocks
- 1. Mandibular Nerve Blocks By – Zibran Khan 1
- 3. Variations of Mandibular Nerve Anatomy Occurrence in 0.95% of cases 3
- 4. Basic Injection Technique 1. Check flow of local anesthetic 2. Position the patient 3. Prepare the tissue 4. Communicate with the patient 5. Establish hand rest 6. Make the tissue taut 7. Keep the syringe out of patient sight 8. Bevel the needle toward the bone 9. Insert the needle 10. Deposit while advancing the needle 11. Aspirate 12. Slowly inject 13. Communicate with the patient 14. Withdraw the needle 15. Cap the needle 16. Watch the patient 17. Record the injection in the patient chart 4
- 5. Techniques of Mandibular Anesthesia Open Mouth Techniques • Inferior alveolar nerve block • Lingual nerve block • Buccal nerve block • Gow-Gates technique • Mental nerve block • Incisive nerve block Closed Mouth Techniques • Varzirani-Akinosi Nerve block 5
- 6. Inferior Alveolar Nerve Block • Not a true Mandibular N. block • Requires supplemental buccal nerve block • May require infiltration of incisors or mesial root of first molar 6
- 7. Inferior Alveolar Nerve Block • Nerves anesthetized • ?????????????? • Areas anesthetized • ??????????????? • Indications • Contraindications 7
- 8. Inferior Alveolar Nerve Block 10%-15% positive aspiration • Alternatives • Mental nerve block • Incisive nerve block • Periodontal ligament injection (PDL) • Gow-Gates • Akinosi • Intraseptal 8
- 9. Inferior Alveolar Nerve Block 9 Bevel
- 10. Inferior Alveolar Nerve Block 10 Bevel towards the bone Bevel away from the bone Needle approaching at right angle
- 11. Inferior Alveolar Nerve Block • 25 guage needle is recommended • Areas of insertion • Mucous membrane on the medial side of the ramus • Target areas • Inferior alveolar nerve just before it enters the mandibular foramen. • Landmarks • Coronoid notch • Pterygoimandibular raphe • Occlusal plane of mandibular posterior teeth Technique 11
- 12. Inferior Alveolar Nerve Block • Orientation of bevel • Towards the bone • Procedure • Operator position • For right IANB- 8 o clock • For left IANB – 10 o clock • Patient position • Supine or semisupine (operator sitting) • Upright (operator standing) Technique 12
- 13. Inferior Alveolar Nerve Block • Locate the insertion point • 3 parameters • Height of injection • Anteroposterior placement • Depth of penetration • Approach the insertion point from the corner of mouth on opposite side. • Insert the needle – when bone contacted, withdraw the needle 1 mm, aspirate and deposit 1.5 ml solution over a period of 60 seconds. Technique 13
- 14. Inferior Alveolar Nerve Block • Withdraw the syringe till half the length, take it on the same side, aspirate and deposit the remaining solution. • Wait 3-5 mins before commencing the dental procedure. • Signs and syptoms • Subjective • Objective • Precautions • Do not deposit if the bone is not contacted. • Do not insert needle too forcefully. 14
- 15. Inferior Alveolar Nerve Block Early bone contact No bone contact 15
- 16. Inferior Alveolar Nerve Block • Failures of anesthesia • Deposition of la below the mandibular foramen • Deposition of la too anteriorly • Accessory innervation • Mylohyoid nerve • Cervical accessory nerve • Bifid inferior alveolar nerve • Cross innervation 16
- 17. Inferior Alveolar Nerve Block • Complication • Hematoma • Trismus • Transient facial palsy 17
- 18. Buccal Nerve Block • AKA Long Buccal Nerve Block • Provides buccal soft tissue anesthesia adjacent to mandibular molars • Not required for most restorative procedures. • Nerve anesthetized • ????????? • Areas anesthetized • ?????? 18
- 19. Buccal Nerve Block • Indication • Anesthesia required in buccal soft tissue in mandibular molar region • Contraindication • Infection/inflammation at injection site. • Positive aspiration – 0.7 % 19
- 20. Buccal Nerve Block • Alternatives • Buccal infiltration • Gow gates mandibular nerve block • Vazirani akinosi mandibular nerve block • Intraligamentary • Intraosseous • Intraseptal 20
- 21. Buccal Nerve Block • 25 gauge long needle recommended • Areas of insertion • Mucous memnrane distal and buccal to the distal molar • Target area • Buccal nerve as it passes over the anterior border of ramus Technique 21
- 22. Buccal Nerve Block • Landmarks • Mandibular molars • Mucobuccal fold • Orientation of the bevel • Towards the bone Technique 22
- 23. Buccal Nerve Block • Operator position • Same as IANB • Patient positon • Same as IANB • With left hand thumb or index finger pull the buccal soft tissue. • Direct the syringe towards the injection site keeping the syringe parallel to the occlusal plane. Technique 23
- 24. Buccal Nerve Block • Penetrate the mucous membrane distal and buccal to the last molar. • Bone contacted • Aspirate • If negative aspiration, Slowly deposit 0.3 ml over 10 seconds. • Withdraw the syring and make needle safe. • Wait for approx. 1 minute before commencing. Technique 24
- 25. Buccal Nerve Block • Signs and symptoms • No subjective symptoms • Objective symptoms • Precautions • Pain on insertion • Local anesthetic solution not being retained at the injection site. 25
- 26. Buccal Nerve Block • Failure - rare • Complication • Hematoma 26
- 27. Gow Gates Technique • By George Albert Edwards Gow-Gates 1973 • It is true mandibular nerve block. • Higher success rate , lower incidence of positive aspiration. • Need clinical experience to master the technique. • Nerves Anesthetized • ????????? 27
- 28. Gow Gates Technique • Areas anesthetized • ??????? 28
- 29. Gow Gates Technique • Indications • Multiple mandibular teeth • Buccal anterior soft tissue • Lingual anesthesia • When conventional inferior alveolar nerve block unsuccessful • Contraindications • Infection/inflammation at injection site • Patients at risk for self injury (eg. children) • patients who are unable to open their mouth wide. 29
- 30. Gow Gates Technique • Advantages • Requires only one injection • High success rate ,with experience. • Minimum aspiration rate 2 % • Provides successful anesthesia where bifid inferior nerve are present. • Disadvantages • The time of onset anesthesia is somewhat longer. • Clinical experience is require to learn the technique. 30
- 31. Gow Gates Technique • Alternatives • IANB & buccal nerve block • Closed mouth mandibular nerve block • Incisive & mental nerve block • Periodontal ligament injection (PDL) • Intraseptal injection 31
- 32. Gow Gates Technique • 25 Gauge long needle used. • Target area • Lateral side of condyle • Landmarks • E/O • Lower border of tragus • Corner of the mouth • I/O • Mesiopalatal cusp of the maxillary 2nd molar Technique 32
- 33. Gow Gates Technique • Orientation of bevel • Not important • Procedure • Request patient to wide open mouth • Locate the extraoral landmarks • Visualize intraoral landmarks • Direct the needle towards the site of injection from corner of mouth from apposite side. • Insert the needle distal to the maxillary second molar. Technique 33
- 36. Gow Gates Technique • Procedure • Location of syringe barrel depends upon divergence of tragus. • The height of insertion is almost 10 t0 25mm above mandibular occlusal plane. • Advance needle until bone contacted. • Withdraw needle 1mm,aspirate & deposit 1.8 ml over 60 sec. Technique 36
- 37. Gow Gates Technique • Signs and symptoms • Subjective • Objective • Precautions • Do not deposit if bone is not contacted • Failure of anesthesia • Too little volume • Anatomical variations 37
- 38. Gow Gates Technique • Complications • Hematoma • Trismus • Transient paralysis of cranial nerves (3, 4, 6) • Diplopia, blepharoptosis 38
- 39. Vazirani Akinosi Mandibular Nerve Block • Mouth Mandibular Block • Dr. Joseph Akinosi reported closed mouth approach to mandibular anesthesia in 1977. • Similar technique was initially described in 1960 by Vazirani. • Wolfe gave modification to this technique in 1992. 39
- 40. Vazirani Akinosi Mandibular Nerve Block • Nerves anesthetized • ???????? • Areas anesthetized – same as IANB • Indications : • Same as IANB • Trismus • Inability to visualize landmarks for IANB (large tongue) • Contraindications : • Infection /acute inflammation in the area of injection. • Patients at risk for self injury (eg. children) 40
- 41. Vazirani Akinosi Mandibular Nerve Block • Advantages • Relatively atraumatic • Low aspiration rate (<10 percent) • Successful in case of bifid inferior alveolar nerve • Disadvantages • Difficulty to visualize the path of needle & depth of insertion • Depth of penetration is somewhat arbitrary. 41
- 42. Vazirani Akinosi Mandibular Nerve Block • Alternatives • ??????????? 42
- 43. Vazirani Akinosi Mandibular Nerve Block • 27 gauge long needle is preferred • Area of insertion • Soft tissue overlying the medial border of ramus directly adjacent to the maxillary tuberosity at the height of the mucogingival junction adjacent to the maxillary third molar. • Target area • Pterygomandibular space (in close approximation of inferior alveolar and lingual nerve) 43 Technique
- 44. Vazirani Akinosi Mandibular Nerve Block • Landmark • Mucogingival junction of maxillary 3rd or 2nd molar. • Maxillary tuberosity • Coronoid notch • Orientation of bevel – away from the bone • Procedure • Operator position • Both left and right Vazirani Akinosi, right handed administrator – 8 o clock facing the position • Patient positiong – supine or semisupine 44 Technique
- 45. Vazirani Akinosi Mandibular Nerve Block • Place index finger or thumb on coronoid notch, reflecting the tissues on the medial aspect of the ramus laterally. • Visualize landmarks • Mucogingival junction of maxillary 3rd or 2nd molar. • Maxillary tuberosity • Prepare the tissue for injection • Ask the patient to occlude with cheek muscles and muscles of mastication relaxed. 45 Technique
- 46. Vazirani Akinosi Mandibular Nerve Block • Syringe is held parallel with the maxillary occlusal plane keeping the needle at the level of the mucogingival junction of maxillary 3rd or 2nd molar. • Direct the needle posteriorly and slightly laterally. • Needle penetration is approximately 25 mm. • Aspirate, if negative, deposit 1.5 to 1.8 ml of anesthetic solution in 60 seconds. • Withdraw and make the needle safe. 46 Technique
- 47. Vazirani Akinosi Mandibular Nerve Block • Anesthesia usually occurs within 60-90 seconds. Wait for 5 minutes before the commencement of procedure. • Signs and symptoms • Subjective – same as IANB • Objective – same as IANB • Precautions • Do not overinsert needle (≤25 mm) • Less needle penetration in a smaller patient • Depth of insertion varies according to ramus anteroposterior size. 47 Technique
- 48. Vazirani Akinosi Mandibular Nerve Block • Failure of anesthesia • Needle directed medially. • Needle inserted too low • Under- or over-insertion • Complications • Hematoma (<10 %) • Trismus (rare) • Transient facial nerve paralysis 48
- 49. Mental & Incisive Nerve block • Mental N. • Terminal branch of IAN as it exits mental foramen • Provides sensory innervation to buccal soft tissue anterior to mental foramen, lip and chin • Incisive N. • Terminal branch of IAN • Originates in mental foramen and proceeds anteriorly 49
- 50. Mental & Incisive Nerve block 50
- 51. Mental & Incisive Nerve block 51
- 52. Mental & Incisive Nerve block 52
- 53. Mental & Incisive Nerve block • Areas anesthetized • Mental ?????? • Incisive ????? • Indication • Mental – only for soft tissue anesthesia • Incisive – teeth anterior to 2nd premolar, B/L anteriors (35 to 45) are to be treated 53
- 54. Mental & Incisive Nerve block • Advantages • High success rate • Easy to perform • Atraumatic • Alternatives • Local infiltration • IANB • Gow gates Mandibular N block • Vazirani Akinosi nerve block 54
- 55. Mental & Incisive Nerve block • 25 gauge short needle is recommended • Area of insertion • Mucobuccal fold at mental foramen • Target area • Mental nerve – as it exits the mental foramen • Incisive nerve – mental foramen from where the incisive nerve continues in the canal 55 Technique
- 56. Mental & Incisive Nerve block • Disadvantage (incisive) • No lingual anesthesia • May require local infiltration due to cross innervation at midline • Advantages(incisive) • Provides pulpal and hard tissue anesthesia without lingual anesthesia • High success rate • Positive aspiration – 5.7 % 56 Technique
- 57. Mental & Incisive Nerve block • Operator position • For right or left block – at 8 o clock position facing the patient • Patient position • Supine or semisupine • Ask the patient to Slightly close the mouth 57 Technique
- 58. Mental & Incisive Nerve block • Locate the mental foramen • Mental foramen is usually found around the apex of second premolar • Place the index finger in the mucobuccal fold and press against the body of the mandible in the first molar area • Move your finger slowly anteriorly until the bone feels irregular and concave • Bone just around the foramen is comparatively rough 58 Technique
- 59. Mental & Incisive Nerve block • Locate the mental foramen • Radiographs – iopa 59 Technique
- 60. Mental & Incisive Nerve block • Prepare the tissue • With left index finger pull the lower lip and buccal tissue laterally • Bevel ????????? • Penetrate the mucous membrane at canine or first premolar region directing the syring to the mental foramen • Depth of insertion – 5-6 mm • No need to enter the foramen 60 Technique
- 61. Mental & Incisive Nerve block • Aspirate, if negative, deposit 0.6 ml over a period of 20 seconds. • For incisive nerve block, maintain gentle finger pressure directly over the injection site to force the solution to enter the foramen. • Withdraw and make the syringe safe. • Wait for 2-3 mins (mental) and 3-5 mins (incisive) before starting. 61 Technique
- 62. Mental & Incisive Nerve block • Signs and symptoms • Subjective ?????? • Objective ????? • Failure – RARE • Complications • Hematoma 62 Technique
- 63. Questions • Which is the true mandibular nerve block • Inferior alveolar nerve block • Gow gates nerve block • Vazirani Akinosi nerve block 63
- 64. Questions • Why do we apply finger pressure on the site of injection in incisive nerve block? • To relieve pain • To spread the la solution in the surrounding soft tissue • To spread the la solution into the canal via the mental foramen 64
- 65. Questions • All these blocks can be used for extraction of 43 except • Inferior alveolar nerve block • Mental nerve block • Incisive nerve block • Gow gates nerve block 65
- 66. Questions • All these blocks can be used for suturing and biopsy of soft tissue anterior to mandibular 2nd premolar • Inferior alveolar nerve block • Mental nerve block • Vazirani Akinosi nerve block • Gow gates nerve block • None of the above 66
- 67. Questions • Which of these blocks is preferred in surgical procedure involving teeth from 35 to 45 • Inferior alveolar nerve block • Mental nerve block • Incisive nerve block • Gow gates nerve block 67
- 68. Answers • Which is the true mandibular nerve block • Inferior alveolar nerve block • Gow gates nerve block • Vazirani Akinosi nerve block 68
- 69. Answers • Why do we apply finger pressure on the site of injection in incisive nerve block? • To relieve pain • To spread the la solution in the surrounding soft tissue • To spread the la solution into the canal via the mental foramen 69
- 70. Answers • All these blocks can be used for extraction of 43 except • Inferior alveolar nerve block • Mental nerve block • Incisive nerve block • Gow gates nerve block 70
- 71. Questions • All these blocks can be used for suturing and biopsy of soft tissue anterior to mandibular 2nd premolar except • Inferior alveolar nerve block • Mental nerve block • Vazirani Akinosi nerve block • Gow gates nerve block • None of the above 71
- 72. Questions • Which of these blocks is preferred in surgical procedure involving teeth from 35 to 45 • Inferior alveolar nerve block • Mental nerve block • Incisive nerve block • Gow gates nerve block 72
- 73. 73
Editor's Notes
- #3: Main trunk lies in the infratemporal fossa and runs deep to lateral pterygoid muscle. Continues anteriorly and divides into anterior and posterior trunk. Branches of mandibular nerve From main trunk – meningeal branch and n to medial pterygoid From anterior trunk – buccal n and massetric, deep temporal and nerve to lateral pterygoid From posterior trunk – auriculotemporal nerve, lingual nerve, inferior alveolar nerve
- #4: Given in chapter 12 of malamed. bifid inferior alveolar nerve
- #7: Nerves anesthetized – ian, menal, incisive, lingual (usually, but may require additional block)
- #8: Nerves anesthetized – ian, menal, incisive, lingual (usually, but may require additional block) Areas Anesthetized - Mandibular teeth to midline, Body of mandible, inferior ramus, Buccal mucosa anterior to mental foramen, Anterior 2/3 tongue & floor of mouth, Lingual soft tissue and periosteum Indications – a procedure involving multiple mandibular teeth in one quadrant, when buccal soft tissue anesthesia ant. To 1st molar is necessary, when lingual soft tissue anesthesia is necessary. CI – infection or acute inflammation in the area of injection, patient who might bite either the lip or tongue for instance (young child or mentally handicapped)
- #14: Height of insertion – thumb on the coronoid notch, 6 to 10 mm above the occlusal plane, Anteroposterior site of injection - insertion llies at 3/4th of anteroposterior distance from coronoid botch back to deepest part of pterygomandibular raphe, place the index finger on posterior border of ramus E/O Pernetration depth – until the bone is contacted, usually 20-25 mm, if bone contacted too early or not contacted. (needle taken out leaving only 1/4th needle inside)
- #15: Subjective – numbness of lower lip and tongue. Objective – no pain during dental therapy
- #17: Bifid inferior alveolar nerve detected in a radiograph. To correct deposit la inferior to the normal anatomical landmark.
- #18: Bifid inferior alveolar nerve detected in a radiograph. To correct deposit la inferior to the normal anatomical landmark.
- #19: Areas anesthetized - Soft tissues & periosteum buccal to mandibular molar teeth Nerve anesthetized – buccal nerve, br of anterior division of mandibular nerve
- #25: Depth of penetration is rarely more than 2-4 mm
- #26: Painless instrumentation is objective symptom
- #27: Failure is due to indadequate volume of anesthetic For hematoma apply pressure with gauze directly to the area of bleeding for a minimum of 3-5 mins.
- #28: True mandibular nerve block as it provides sensory anesthesia to virtually the entire distribution of mandibular nerve. Nerves anesthetized - Inferior alveolar, Mental, Lingual, Mylohyoid, Auriculotemporal , Buccal (in 75 % cases)
- #29: Mandibular teeth to the mid line. Buccal periosteum Anterior two third of the tongue & floor of mouth Lingual soft tissue & periosteum Body of the mandible, inferior portion of ramus Skin over the zygoma, posterior portion of the cheek, temporal region
- #33: Height of injection is established by placement of needle tip just below the mesiopalatal cusp of maxillary 2nd molar
- #38: Subjective – numbness in lip n tongue. Tongue numbness indicates successful gow gates When bone is not contacted – withdraw, redirect needle laterally, reinsert and make gentle bone contact
- #39: 3 – occulomotor 4 – trochlear 6 – abducens Blephar-optosis - drooping of upper eyelid.
- #40: Wolfe modification – identical to the original technique, just one modification. Bending the needle at 45 degree angle to enable it to remain in close proximity to the medial side of the mandibular ramus. But as on bending the needle, the chances of needle breakage is more so it is not advised to insert the needle to significant depth. Bending needle usually not needed. Can be successfully given without bending the needle.
- #41: Nerves anesthetized - Inferior alveolar, Incisive, Mental, Lingual, Mylohyoid Areas anesthetized – mandibular teeth to midline, body of mandible and inferior portion of ramus, buccal mucoperiosteum and mucous membrane in front of mental foramen, anterior 2/3rd of tongue and floor of the oral cavity, lingual soft tissue and periosteum
- #43: No intraoral injection technique is available, only other option available is Extraoral technique.
- #44: Height of injection is more than the ianb but less than gow gates.
- #45: Here we are not going to contact the bone and it is important to keep the needle close to the medial surface of ramus, the bevel facing medially will force the needle laterally close to the ramus.
- #49: Needle directed medially – corrected by directing needle laterally and using 27 gauge needle. Needle inserted too low – insert needle at or slightly above the level of mucogingival junction and needle to be parallel to occlusal plane. Under or overinsertion – needle to be inserted max 25 mm in average adult.
- #54: Mental – buccal mucous membranes anterior to mental foramen to midline and skin of lower lip and chin Incisive – same as mental, pulpal anesthesia from 2nd premolar to midline. Soft tissue anesthesia – suturing, biopsy
- #58: Initially the position was 11 o clock position. But in this position the needle is in direct line of sight of the patient, which is psychologically traumatic. So it is changed to front position.