MANDIBULAR NERVE BLOCKS and techniques in dentistry

mandibular nerve blocks

1. MANDIBULAR NERVE BLOCKS 1 Presented by Dr. Raji CH Guided by Dr. Ashwin D P

2. CONTENTS INTRODUCTION TRIGEMINAL NERVE REGIONAL ANATOMY ANATOMY OF MANDIBLE COURSE OF MANDIBULAR NERVE ANATOMY OF PTERYGOMANDIBULAR SPACE ANALGESIA TECHNIQUES : EXTRA ORAL AND INTRA ORAL INFERIOR ALVEOLAR NERVE BLOCK LINGUAL NERVE BLOCK LONG BUCCAL NERVE BLOCK MENTAL AND INCISIVE NERVE BLOCK MANDIBULAR NERVE BLOCK CAUSES OF FAILURE OF REGIONAL ANESTHESIA CONCLUSION REFERENCES

3. INTRODUCTION The mandibular nerve block techniques are described in a pattern that begins with the more central innervation and moves towards the periphery. Because the neuroanatomy of the mandibular nerve and the denseness of the mandible make blocking the entire inferior alveolar branch of the mandibular nerve as the method of choice. Blocking the inferior alveolar branch affects all its terminal branches.

4. TRIGEMINAL NERVE 5 th cranial nerve Largest Composed of small motor root large sensory root

5. TRIGEMINAL NERVE

6. TRIGEMINAL NERVE

7. MANDIBULAR DIVISION

8. COURSE OF MANDIBULAR NERVE AND ITS BRANCHES

9. REGIONAL ANATOMY ANATOMY OF MANDIBLE Strongest and largest bone of the face Develops from first pharyngeal arch It has horse shoe shaped body which lodges teeth, Pair of rami which projects upward from the posterior ends of the body The rami provide attachments to the muscles of mastication

10. FEATURES OF THE MANDIBLE

11. ANATOMY OF PTERYGOMANDIBULAR SPACE

12. BOUNDARIES OF THE PTERYGOMANDIBULAR SPACE

13. MANDIBULAR NERVE BLOCKS INFERIOR ALVEOLAR NERVE BLOCK LINGUAL NERVE BLOCK LONG BUCCAL NERVE BLOCK INCISIVE MENTAL NERVE BLOCK MANDIBULAR NERVE ITSELF

14. CLASSIFICATION OF INFERIOR ALVEOLAR NERVE BLOCKS : Niraj S Gokhale., et al. “Alternative Approaches for Inferior Alveolar Nerve Technique in Children: A Review”. Acta Scientific Dental Sciences 3.2 (2019): 10-16.

15. CLASSIFICATION OF IANB TECHNIQUES IANB TECHNIQUES INTRA ORAL EXTRAORAL OPEN MOUTH CLOSED MOUTH : Niraj S Gokhale., et al. “Alternative Approaches for Inferior Alveolar Nerve Technique in Children: A Review”. Acta Scientific Dental Sciences 3.2 (2019): 10-16.

16. OPEN MOUTH TECHNIQUES DIRECT TECHNIQUE/CONVENTIONAL MODIFICATION-a) CHARLES HOPKINS b) ANGELO SERGENTI DIRECT THRUSH TECHNIQUE BY MENDEL NEVIN MODIFICATION-a) BORIS LEVIT b) I R BROWENLEE INDIRECT TECHNIQUE MODIFICATION-a) FISCHER 1 2 3 CLARK AND HOLMES ANTERIOR RAMUS TECHNIQUE CURVED NEEDLE TECHNIQUE CLOSED MOUTH TECHNIQUES SUNDER J VAZIRANI TECHNIQUE AKINOSI TECHNIQUE VAZIRANI-AKINOSI TECHNIQUE EXTRAORAL TECHNIQUE KURT THOMA TECHNIQUE

17. ALTERNATIVE TECHNIQUES BOONSIRISETH TECHNIQUE NOOH AND ABDULLA TECHNIQUE TAKASUGI et al TECHNIQUE SAUZO GALDAMES THANGAVELU THANGAVELU(2012) PALTI et al TECHNIQUE SPECIFIC FOR PEDIATRIC PATIENTS INVERTED TRIANGLE CONCEPT BY MATHEWSON THUMB CONCEPT BY WRIGHT LINGULA TECHNIQUE

18. INFERIOR ALVEOLAR NERVE BLOCK Second most frequently used technique. Dr. William S Halsted was the first one to show in 1844 , that the inferior alveolar nerve can be blocked successfully at the mandibular sulcus.

19. INDICATIONS: Multiple mandibular teeth Buccal soft tissue anesthesia Lingual soft tissue anesthesia CONTRAINDICATIONS: Infection or acute inflammation Patients who are most likely to bite their lip or tongue

20. NERVES AND AREAS ANESTHETISED

21. Position of the administrator right inferior alveolar nerve block (A) and left inferior alveolar nerve block (B)

22. ANATOMICAL LAND MARKS: Mucobuccal fold Anterior border of the ramus of the mandible External oblique ridge Retromolar triangle Internal oblique ridge Pterygomandibular ligament Buccal sucking pad Pterygomandibular space

23. TECHNIQUE:

24. ADVANTAGES: Wide area of anesthesia DISADVANTAGES: Not for localized procedures Rate of inadequate anesthesia Intraoral landmarks not consistently reliable Lingual and lower lip anesthesia Partial anesthesia

25. Relation of lower alveolar nerve to the groove of the mandibular neck when Jaws open and closed.

26. Relation of lower alveolar nerve to the groove of the mandibular neck when Jaws open and closed.

27. COMPLICATIONS OF IANB TRISMUS HEMATOMA (rare) TRANSIENT FACIAL PARALYSIS NEEDLE BREAKAGE

28. HEMATOMA

29. NEEDLE BREAKAGE

30. TRANSIENT FACIAL PARALYSIS

31. An inferior alveolar nerve block anaesthesia has a low success rate due to two factors: (1) anatomical variation from the height of the mandibular foramen on the lingual portion of the ramus and (2) required a considerable penetration depth in the soft tissues, leading to high inactivity. (3) The success of anaesthesia in mandibular teeth is difficult to obtain consistently.

32. ALTERNATIVE TECHNIQUES Many alternative approaches to the inferior alveolar nerve bock technique have been described in the literature, all of which aim to achieve a high success rate, reduce the risk of intravascular injections and finally, avoid damage to the nerve.

33. DIRECT METHOD

34. CHARLES HOPKINS TECHNIQUE (1959) D eveloped by Dr.Charles B.Hopkins , T he needle is inserted perpendicular to the ramus W ith the barrel in relation to 1 st and 2 nd molar of opposite side. The height of insertion is above the finger nail of the palpating finger on the coronoid notch. According to Hopkins the solution in this technique is deposited directly into the mandibular sulcus unlike Mendel Nevin’s thrust technique where in the solution is deposited at the posterior boundary of the sulcus.

35. ANGELO SARGENTI’S TECHNIQUE Given by Sargenti Modification of the direct method. The principle difference is that the nerve is approached from a higher level than usual The point of the needle insertion is opposite the midpoint of the fingernail but the barrel of the syringe placed between and in contact with the opposite side upper premolar, the needle being inserted in a downward and backward direction

36. ANGELO SERGENTI TECHNIQUE

37. DIRECT THRUSH TECHNIQUE BY MENDEL NEVIL Popularized by Dr. Mendel Nevil . The guide finger is placed on the coronoid notch. The needle is inserted into the pterygotemporal depression in the pterygomandibular space. Needle will encounter the posterior wall of the mandibular sulcus where the solution is slowly deposited. when withdrawing the needle, the syringe is brought in line with the lower teeth of the same side of the injection and the remaining solution is injected to anaesthetize the lingual nerve.

38. MODIFIED DIRECT THRUSH TECHNIQUE BY BORIS LEVITT 1935 M odification of Mendel’s direct thrust technique in “modern dentistry”. his technique differs in the following aspects. The height of insertion Secondly,depth no greater than 1 inch The lingual nerve should be anaesthetized by withdrawing the needle halfway and depositing the remaining solution and not by swinging the needle to the same side which may result in needle breakage

39. Dr.BROWNLEE DIRECT THRUSH TECHNIQUE D r.I.R.Brownlee first described the importance of posterior border of ramus as a landmark in mandibular inj. He advocated the placement of thumb over the coronoid notch, index finger over the posterior border of ramus and the third finger over the angle of mandible extraorally respectively Advantages of the technique are: A firm hold of the jaw and more control is obtained. A direct thrust to the centre of the line between thumb and the finger ensures an injection close to the foramen The technique depends on no unreliable landmarks such as occlusal surface so it works equally well on dentulous or edentulous mandibles, young or old patients, at the hospital bed or dental chair

40. INDIRECT METHOD

41. FISCHER TECHNIQUE

42. FISCHER TECHNIQUE

43. CLARK AND HOLMES METHOD(1959)

44. ANTERIOR RAMUS TECHNIQUE The anterior border of the ramus is palpated and the coronoid notch is identified with the thumb. The middle finger and the thumb are used to determine the width of the ramus in its anterior-posterior dimension. The average width of the ramus, including the thickness of the soft tissue in the coronoid notch, is approximately 35mm, which is also the length of the needle. Inject the needle until bone in the coronoid notch is contacted. The syringe and needle at this stage are buccal to the posterior molars.

45. ADVANTAGES: Simple to learn and easy to accomplish It is not associated with high risks or numerous complications Good anatomical landmarks It utilizes the lower portion of pterygomandibular space. Unlike the Gow-Gates and Akinosi , there is no danger of injecting the needle and depositing the local anaesthetic contents into the maxillary artery and vein, the middle meningeal artery and vein or the temperomandibular joint capsule

46. ARCHED NEEDLE TECHNIQUE

47. ADVANTAGES Success rate 98% More accurate deposition of the solution No specific maneuver was used to anesthetise the lingual nerve DISADVANTAGES Equipment specific Not meant for in experienced operators Tissue may tear with large bore needles

48. BOONSIRISETH TECHNIQUE

49. ADVANTAGES stopper to indicate the depth of insertion Depth of penetration is less then conventional Needle tip is parallel to neuro vascular bundle No movement of the syringe Less systemic complications from positive aspiration DISADVANTAGES Syringe too buccal to the alignment of teeth may lead the needle tip away from mandibular foramen.

50. THANGAVELU (2012) TECHNIQUE Patient is advised to sit in semi supine position and few inches below the operator’s elbow level in the dental chair 2. The patient is advised to open the mouth fully so that the occlusal table of mandible is parallel to the floor. 3. The operator’s thumb finger is placed over the anterior border of ramus that helps in retraction of tissues mildly as shown in Figure 1. 4. Imaginary midpoint between the upper occlusal plane and lower occlusal plane, in anterior border of ramus is selected [Figure 2] or coronoid notch in the anterior border of mandible is identified. 5. 6 to 8 mm above this midpoint or coronoid notch and 8 to 10 mm posterior to the anterior border of ramus is the first site of insertion of needle as shown in Figure 2. 6. The barrel of the syringe is placed between canine and premolars of contra lateral side of extraction and the needle is inserted at the selected site of insertion [Figure 3].

51. 7. Now the needle is advanced till it hits the bone that is the medial side of ramus behind anterior border of ramus. Few drops of the Local anesthetic solution are deposited at this place. This may anesthetize the long buccal nerve 8. The thumb finger over anterior border of ramus is withdrawn and allows the free movement of tissues over anterior and medial side of ramus. The barrel of syringe is adjusted towards midline of mandible to insert the needle freely further along the medial side of ramus. 9. ‘During the course of injection few drops of Lignocaine solution is being deposited to anesthetize the path of insertion and lingual nerve. Here closeness of needle to the medial side surface of ramus is important than position of barrel of syringe. The closeness of needle to ramus is confirmed by frequent touch of tip of the needle on the bone of ramus during the course of injection. 10. The needle is advanced further into the tissues supra periosteally towards the target area above the mandibular foramen by following the medial side of ramus as guide

52. 11. When 21 to 24 mm length of the needle is inserted from anterior border of ramus, needle distance with anterior border of ramus was verified as shown in Figure 4. According to Malamed study the distance between mandibular foramen and anterior border of ramus is 20 to 24 mm.[14] 12. Now the tip of needle would be superior to IAN entry into its mandibular foramen. 13. To bring the tip of needle closer to bone and IAN the barrel of the syringe is taken back to the contra lateral side. The closeness of tip of needle to bone is confirmed by resistance of bone for further entry of needle as shown in Figure 5. 14. One to 1.5 mL of local anesthetic solution should be deposited at this place (pterygomandibular space) to anesthetize inferior alveolar nerve. 15. To prevent failure of anesthesia spread the deposition of solution equally from 21 mm distance to 24 mm distance of needle. This helps in deposition of solution over wide area. 16. To achieve buccal nerve anesthesia, few drops of local anesthetic solution should be injected into the tissues adjacent to the tooth to be extracted.

53. ADVANTAGES: Non reliability on several landmarks DISADVANTAGES: Anatomical variation of mandibular foramen in patients may cause the need of second injection to produce satisfactory level of anesthesia

54. THANGAVELU TECHNIQUE USING ITERNAL OBLIQUE RIDGE AS A LAND MARK

55. ADVANTAGES: Simple technique as there is only one landmark DISADVANTAGES: Non reliability

56. TAKASUGI TECHNIQUE

57. PALTI TECHNIQUE

58. ADVANTAGES: anatomical reference using two fixed points success rate of 80.82% for the permanent dentition and 93.62% for the primary dentition DISADVANTAGES: the possible anatomical variations were not taken into consideration

59. AKINOSI

60. The dentist stands in front and to the right of the patient. The teeth are closed to aid relaxation of the cheek muscles which are then well distended for good vision. The needle is positioned at the level of the maxillary marginal gingivae and with the barrel parallel to the maxillary occlusal plane, the syringe is then advanced and the needle then penetrates the tissues in the embrasure between the vertical ramus and maxillary tuberosity. Between 2.5 cm and 3 cm of the needle is buried in the tissues at this site and about 1.5 cc to 2 cc of anaesthetic solution is slowly deposited.

61. The needle at this point lies in the pterygo -mandibular space having passed through the buccinator muscle. It is in close relationship with the main branches of the mandibular nerve in this situation and are easily reached by diffusion of the anaesthetic solution. The needle is then slowly withdrawn.

62. Vazirani- Akinosi technique A. depicting the Vazirani- Akinosi technique on a skull model; B and C. depicting the technique in a patient

63. ADVANTAGES Ability to produce anesthesia of the entire distribution of the mandibular nerve with a single needle penetration. DISADVANTAGES Relies on soft tissue landmarks that may vary markedly from patient to patient The fovea the one bony landmark that must be identified, is quite small and often difficult to locate

64. CAUSES OF FAILURE OF REGIONAL ANALGESIA Insufficient knowledge of the local anatomy of the region Individual anatomical variations Variations due to age Faulty technique

65. VARIATION IN BIFID MANDIBULAR CANAL

66. UNUSUAL ANATOMIC VARIATION OF IAN Variation of the inferior alveolar nerve https://doi.org/10.5115/acb.20.145 Anat Cell Biol 2020;53:519-521 by Shogo Maekawa, et al

67. FACTORS AFFECTING THE RELATIVE POSITION OF THE MANDIBULAR FORAMEN Width of the ascending ramus Width of arch of mandible Obliquity of the angle of the mandible

68. . Modified Indirect IANB Technique by Nooh et al (2010)

69. S J VAZIRANI TECHNIQUE(1960)

70. EXTRAORAL TECHNIQUE BY KURT AND THOMA A. depicting the markings for the Kurt- Thoma technique; B. a rubber stopper was placed for the needle and the length of insertion was measured; C. insertion of the needle at the inferior border of the mandible

71. MANDIBULAR NERVE BLOCK TECHNIQUES Gowgates method Intraoral approach(1973) and Extra oral approach Vazirani- akinosi method

72. GOW-GATES TECHNIQUE In 1973 Gow-Gates described a true mandibular nerve block A single anesthetic injection provides hard and soft tissue anesthesia of the mandible to the midline.

73. GOW GATES TECHNIQUE

74. EXTRAORAL LANDMARKS

75. INTRA ORAL LANDMARKS

76. VAZIRANI AKINOSI CLOSED MOUTH MANDIBULAR NERVE BLOCK TECHNIQUE

77. EXTRAORAL MANDIBULAR NERVE BLOCK

78. EXTRAORAL MENTAL NERVE BLOCK

79. EXTRAORAL MENTAL NERVE BLOCK

80. TECHNIQUES SPECFIC FOR PEDIATRIC PATIENTS INVERTED TRIANGLE CONCEPT BY MATHEWSON Coronoid notch is palpated using a guide finger. An imaginary triangle is formed by anterior border of ramus,internal pterygoid muscle and the vault of palate, apex directed inferiorly and Another imaginaryline which divides the tip of the finger or the thumb positioned at the coronoid notch passing medially over a depression area above the apex. Once bone is contacted,the solution is deposited

81. THUMB CONCEPT BY WRIGHT 2)For a right inferior alveolar nerve block , the left thumb nail is positioned at the coronoid notch and slightly over the deep tendon of the temporalis muscle , pterygomandibular raphae Being medial to the thumb. The needle is inserted at the middle of the thumbnail , btw deep tendon of temporalis(laterally) and pterygomandibular raphae (medially) entering the mandibular sulcus at the level of the lingual notch

82. LINGULA CONCEPT The technique was developed taking into the consideration the level of mandibular foramen of pediatric patients which is at lower level than occlusal level of the primary teeth. Therefore the needle to be inserted at the lower level and posterior as compared to in adults. The anterior and posterior borders of ramus are palpated for targeting the lingula.

83. BUCCAL NERVE BLOCK

84. INDICATIONS When buccal soft tissue anesthesia is needed CONTRAINDICATIONS Infection or acute inflammation in the area of injection ADVANTAGES High success rate Technically easy DISADVANTAGES Potential for pain if the needle contacts the periosteum during injection

85. TECHNIQUE

86. MENTAL NERVE BLOCK It is the least frequently employed technique Buccal mucous membrane anterior to mental foramen INDICATION : buccal soft tissue anesthesia is necessary anterior to mental foramen CONTRA INDICATION : infection ADVANTAGES : High success rate Technically easy Atraumatic DISADVANTAGES : Hematoma

87. NERVES AND AREAS ANESTHETISED

88. TECHNIQUE A 25 or 27 gauge short needle Patient position : supine or semi supine Area of insertion : mucobuccal fold just anterior to mental foramen Target area : mental foramen as it exits the mental foramen Landmarks : mandibular premolars and mucobuccal fold

89. INCISIVE NERVE BLOCK

90. TECHNIQUE A 27-gauge short needle is recommended. 2. Landmarks: Mandibular premolars and mucobuccal fold. 3. Orientation of the bevel: toward bone during the injection. 4. Target area: mental foramen, through which the mental nerve exits and inside of which the incisive nerve is located. 5. Area of insertion: mucobuccal fold at or just anterior to the mental foramen.

91. CONCLUSION Many techniques for the anaesthesia of inferior alveolar nerve have been described. Although many techniques for inferior alveolar nerve block have been described in the literature, most dentists still use the conventional block approach. . Each technique has its own advantages and disadvantage. A method can however, not be judged only by comparing notes on success. Only a method should be adopted that can be taught in exact terms and that the average student can learn so that he is sure of successful anaesthesia.

92. REFERENCES Bennet, “monheims local anaesthesia and pain control in dental practise.” 7 th edition Malamed SF. Handbook of local anesthesia. 4th ed. St Louis: Mosby; 1997. p. 86, 203. DH Roberts and JH Sowray . “Regional Analgesia”. In: Local analgesia in dentistry, 3rd edition, IOP publishing limited Techno Oral anatomy By Harry Sichers 3 rd ED house Redeliffe way, Bristol (1987): 102-129. . Takasugi Y, Furuya H, Moriya K, Okamoto Y. Clinical evaluation of inferior alveolar nerve block by injection into the pterygomandibular space anterior to the mandibular foramen.  Anesth Prog.  2000;47:125–9.  . Palti DG, Almeida CM, Rodrigues Ade C, Andreo JC, Lima JE. Anesthetic technique for inferior alveolar nerve block: A new approach.  J Appl Oral Sci.  2011;19:11–5. Thangavelu K, Kannan R, Senthil Kumar N. Inferior alveolar nerve block: Alternative technique.  Anesth Essays Res.  2012;6:53–7. Thangavelu K, Sabitha S, Kannan R, Saravanan K. Inferior alveolar nerve block using internal oblique ridge as landmark.  SRM Univ J Dent Sci.  2012;3:15–8. .

93. Boonsiriseth K, Sirintawat N, Arunakul K, Wongsirichat N. Comparative study of the novel and conventional injection approach for inferior alveolar nerve block.  Int J Oral Maxillofac Surg.  2013;42:852–6 . Suazo Galdames IC, Cantin Lopez MG, Zavando Matamala DA. Inferior alveolar nerve block anesthesia via the retromolar triangle, an alternative for patients with blood dyscrasias.  Med Oral Patol Oral Cir Bucal .  2008;13:E43–7. Chakranarayan A, Mukherjee B. Arched needle technique for inferior alveolar mandibular nerve block. Journal of maxillofacial and oral surgery. 2013 Mar;12:113-6. : Niraj S Gokhale., et al. “Alternative Approaches for Inferior Alveolar Nerve Technique in Children: A Review”. Acta Scientific Dental Sciences 3.2 (2019): 10-16.

94. THANK YOU

95. ATTATCHMENTS AND RELATIONS OF THE MANDIBLE