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Intraoral nerve blocks for orofacial anesthesia
Intraoral Nerve Blocks for Orofacial Anesthesia By ThomasGlennIson, DMD LOUISVILLE, KENTUCKY
P ,
ROCEDURES REQUIRING anesthesia of the face and intraoral structures are common in emergency departments. Local infiltration can be time-consuming and painful, especially on an apprehensive or uncooperative patient. Intraoral regional nerve blocks are an excellent alternative and have several advantages over local infiltration: (1) They provide anesthesia over a wider area and with less anesthetic agent; (2) regional nerve blocks require only a single injection; (3) tissue distortion is rarely a problem, as solution is deposited away from the operative site; (4) intraoral injections can be less painful with use of topical anesthetic agents; (5) and patients may already be familiar with dental block injections.1 One disadvantage to the regional block is limited hemostasis. Local infiltration with a vasoconstrictor can be performed without pain after regional block. Factors influencing the choice of local anesthesia include the patient’s medical history, drug allergy, weight, area to be anesthetized, duration of anesthesia, and need for vasoconstriction. The 2 main classes of local anesthetics are ester and amide types. Esters are hydrolyzed by pseudocholinesterase in the plasma, whereas amides are predominantly metabolized in the liver.2 Impaired ability to metabolize an anesthetic should be considered in the decision. Patients with allergy to an ester type can be treated with an amide type. True allergic reaction to an amide is rare, and patients often report syncopal reactions as an allergy.3 Most local anesthetics are vasodilators. The addition of a vasoconstrictor offers several advantages including the following: (1) decreased blood flow to site of injection, (2) decreased absorption into bloodstream lessening likelihood of overdose, and (3) prolonged anesthesia by having higher concentrations around the nerve. 270
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIA/ THOMAS GLENN ISON
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIA/ THOMAS GLENN ISON
Lidocaine, an amide, is the most commonly used agent for dental anesthesia.1 It is available in a single-use dental cartridge (1.8 mL) as a 2% solution without vasoconstrictor, with 1:50,000 epinephrine, and with l:lOO,OOO epinephrine. Two percent lidocaine with l:lOO,OOO epinephrine can provide soft-tissue anesthesia lasting 3 to 4 hours2 Comparable anesthesia success has been reported for 2% lidocaine with 1:50,000 epinephrine and l:lOO,OOO epinephrine.4 The use of 2% lidocaine with 1:50,000 epinephrine is usually reserved for infiltration in which hemostasis is desired. Mepivacaine 3%, an amide, is often used in patients where vasoconstrictors are contraindicated. It provides 20 to 40 minutes of pulpal anesthesia and 2 to 3 hours of soft-tissue anesthesia. Bupivacaine 0.5% with 1:200,000 epinephrine is a long-acting amide that can be used for pain control after a procedure. Soft-tissue anesthesia can last 5 to 8 hours, but its onset (6 to 10 minutes) is slower than the other agents. The maximum dose of lidocaine and mepivacaine is 4.4 mg/kg; bupivacaine maximum dose is 1.3 mg/kg.2 Topical anesthetic agents are available to provide mucosal surface anesthesia before intraoral injection. Although the lidocaine solution can be used for topical anesthesia, concern arises over greater potential of toxicity from overdose. Dentists typically use flavored 20% benzocaine gels (Fig 1). Applied with a cotton-tipped applicator or cotton roll to dried oral mucosa, it provides surface anesthesia in 30 to 60 seconds, allowing for atraumatic needle penetration. The taste or sensation on the tongue may be unpleasant to young children and result in compliance problems. The dental syringe (Fig 1) is easily used for intraoral injections, although the standard syringe can be used. The thumb ring allows for l-hand
Figure I. Topical dental syringe.
anesthetic,
1.8 mL anesthetic
carpule, and
Figure 2. Facial area anesthetized
by infraorbital
271
nerve block.
aspiration, allowing the free hand to be used for retraction of tissues and stabilization of the patient. Single-use cartridges containing 1.8 mL of anesthetic are used. Twenty-five-, 27-, and 30-gauge, long (40 mm) and short (25 mm), needles are available and used according to personal preference. Pediatric dentists usually use the 30-gauge needle. The long needle should be used when deeper penetration of tissues is required, such as for inferior alveolar and infraorbital injections. Short needles are used for infiltration and nerve blocks in younger children.
lnfraorbital NerveBlock The infraorbital nerve is a terminal branch of the maxillary division of the trigeminal nerve. Extraorally, it provides sensory innervation to the lower eyelid, lateral nose, cheek, and upper lip, to the midline (Fig 2). Intraorally, it innervates the buccal and labial mucosa and gingiva, extending from the second primary molar (or second premolar in the permanent dentition) to the midline. The infraorbital foramen can be located by palpating the maxilla along a line extending from the supraorbital notch, pupil in forward gaze, and infraorbital notch of the orbital rim.5 Indication for this nerve block is the need for anesthesia of these soft tissues, such as in biopsy, debridement, or repair of lacerations of the cheek, lip, lower eyelid, or intraoral mucosa. In addition, diffusion of the anesthetic through the bone will block the anterior superior nerve, providing pulpal anesthesia to the canine and incisors. Bilateral blocks will provide complete anesthesia to the maxillary lip.
272
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIAI THOMAS GLENN ISON
Figure 3. Position of needle penetration tion.
for infraorbital
injec-
Technique Dry mucosa and place topical anesthetic in the depth of the labial vestibule just distal to the canine. Palpate the infraorbital foramen. Retract the lip, pulling the mucosa taut (Fig 3). Insertion is in the height of the vestibule just distal to the canine. Place the needle parallel to the long axis of the canine with the bevel facing the maxilla. Slowly advance the needle towards the foramen with the use of your finger as a guide. You may palpate the needle as it approaches the foramen. The needle should contact the superior rim of the foramen. Retract the needle from the periosteum and aspirate to ensure that a vessel has not been entered. Slowly inject 0.5 to 1.0 mL over the foramen (Fig 4). Success will be shown by anesthesia of the aforementioned soft tissues. Pulpal anesthesia of
Figure 5. Facial area anesthetized
by mental nerve block.
the incisors, canine, and primary molars (or permanent premolars) will also be obtained.
MentalNerveBlock
Figure 4. Needle position at infraorbital
foramen.
The mental nerve is a terminal branch of the mandibular division of the trigeminal nerve. Extraorally, it provides sensory innervation to the skin of the lower lip and chin from the commissure extending anteriorly to the midline (Fig 5). Intraorally, it innervates the alveolar mucosa, gingiva, and labial mucosa, extending anteriorly from the primary molar (premolar in older children) area to the midline. The mental foramen is located on the lateral aspect of the mandible, usually at the apices, between the primary molars (or premolars in older children) (Fig 6). The mental foramen can be located by palpating in the area of the primary molars. The mandible will feel smooth anterior and posterior to the foramen. Indication for this nerve
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIA/ THOMAS GLENN ISON
Figure 6. Mental foramen located in area of primary apices and position of needle for block.
273
molar
block is the need for anesthesia of these soft tissues such as in biopsy, debridement, or repair of lacerations of the lower lip or intraoral mucosa. Lacerations involving the commissure may also require buccal and infraorbital nerve blocks.
Technique Palpate the mental foramen. Dry the mucosa and place topical anesthetic in the depth of the vestibule in the area of the foramen. Retract the lip, pulling the tissue taut (Fig 7). With the bevel of the needle towards the bone, penetrate the mucosa slightly anterior to the foramen. Slowly advance the needle to the depth of the foramen. Aspirate. Slowly inject approximately 0.5 to 1.0 mL. Success will be shown by tingling of the lower lip.
BuccalNerveBlock The buccal nerve is a terminal branch of the mandibular division of the trigeminal nerve. It
Figure 8. Facial area anesthetized
by buccal nerve block.
crosses from the medial to the lateral aspect of the mandible, anterior to the ramus on a level of the occlusal plane. It provides sensory innervation to the skin of the cheek (Fig S), buccal mucosa, and gingiva in the molar area.
Technique Dry the mucosa of the buccal vestibule distal to the molars and apply topical anesthetic. Retract the cheek pulling the mucosa taut. Slowly penetrate the buccal vestibular mucosa, distal to the molars, until the periosteum is contacted (Fig 9). Aspirate. Slowly inject 0.5 mL. Tingling of the cheek will indicate success.
Inferior AlveolarNerveand LingualNerve
Figure 7. Mandibular lip retracted and position of needle for left mental nerve block.
The inferior alveolar nerve is a branch of the mandibular division of the trigeminal nerve. It is located in the pterygomandibular space lateral to the sphenomandibular ligament and medial to the ramus of the mandible. It enters the mandibular foramen, located in the middle to posterior third of the ramus (Fig 10). It provides sensory innervation to the buccal mucosa and gingiva anterior to the primary molars, skin of the chin, and lip. The lin-
274
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIAI THOMAS GLENN ISON
Figure 9. Injection site in mandibular buccal nerve block.
left posterior
vestibule for
gual nerve branches from the mandibular division of the trigeminal nerve and courses anteriorly and medially to the inferior alveolar nerve. It provides sensory innervation to the lingual gingiva, floor of the mouth, and anterior two thirds of the tongue to the midline. Anesthesia of the inferior alveolar nerve usually results in anesthesia to the lingual nerve. Indications for the inferior alveolar nerve block include the need for pulpal and soft-tissue (gingiva, labial mucosa, lower lip, and skin of chin) anesthesia, such as in debridement or repair of lacerations
Figure IO. Medial view showing right mandibular foramen in middle (anterior-posterior) of ramus. Needle positioned (from anterior) for inferior alveolar nerve block.
Figure I I. Syringe from penetrating the mucosa a left inferior alveolar positioned against the mandible.
right corner of mouth with the needle in the left pterygomandibular fossa for or lingual nerve block. The thumb is coronoid notch of the ramus of the
and treatment of odontogenic injuries. Bilateral inferior alveolar blocks are not usually recommended for younger children, as they may be prone to selfmutilation by biting the anesthetized lip or tongue because of loss of proprioception.
Technique To locate the site of injection, have the patient open the mouth wide. Place the thumb of the free hand, intraorally, on the coronoid notch, stretching the mucosa of the pterygomandibular triangle (Fig 11). Grasp the posterior border of the ramus with the forefinger. The line between the thumb and forefinger serves as the height of injection, with the midpoint being the antero-posterior target. Dry the mucosa and place topical anesthetic. The angle of needle insertion is from the opposite corner of the mouth, overlying the primary molars or premolars (Fig 12). Slowly advance the needle until bone is contacted. Move the barrel of the syringe slightly toward the midline, so that the needle parallels the ramus, and advance the tip to the foramen. Depth of insertion is usually between 1 to 2 cm, estimated by the midpoint of the thumb and finger position. Aspirate to ensure a vessel has not been entered. Slowly deposit 1.0 to 1.5 mL. To anesthetize the lingual nerve, withdraw the needle halfway. Aspirate. Slowly deposit 0.5 mL. Success will be noted by anesthesia of the lower lip and chin (mental nerve) for the inferior alveolar nerve and the lateral portion of the tongue for the lingual nerve. Lingualnerve anesthesia will occasionally be obtained with-
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIA / THOMAS GLENN ISON
275
Summary Orofacial anesthesia for biopsy, wound debridement, laceration repair, or treatment of odontogenie injuries can be easily obtained by intraoral nerve block. Dental injection techniques offer several advantages over local infiltration, including patient familiarity with the procedure. The practitioner should be knowledgeable of the anesthetic agent and prepared for any adverse reaction.
References
Figure 12. The path of insertion for an inferior alveolar or lingual nerve block has the barrel of the syringe overlying the opposite primary molars (or premolars in older patients).
out inferior alveolar anesthesia, indicating the block was placed too far anteriorly. The inferior alveolar nerve block is often missed also by injecting below the level of the mandibular foramen.
1. Kretzschmar JL, Peters JE: Kerve blocks for regional anesthesia of the face. Am Fam Physician 55:17011704, 1997. 2. Malamed SF: Handbook of Local Anesthesia. St Louis, MO, Mosby, 1986. 3. Panje WR: Local anesthesia of the face. J Dermatol Surg Oncol 5:311-3X, 1979. 4. Yared GM, Dagher FB: Evaluation of lidocaine in human inferior alveolar nerve block. J Endod 23:575578, 1997. 5. Zide BM, Swift R: How to block and tackle the face. Plas Reconstr Surg 101:840-851, 1998. 6. Trebus DL, Singh G, Meyer RD: Anatomical basis for inferior alveolar nerve block. Gen Dent 46:632-636, 1998.
P ,
ROCEDURES REQUIRING anesthesia of the face and intraoral structures are common in emergency departments. Local infiltration can be time-consuming and painful, especially on an apprehensive or uncooperative patient. Intraoral regional nerve blocks are an excellent alternative and have several advantages over local infiltration: (1) They provide anesthesia over a wider area and with less anesthetic agent; (2) regional nerve blocks require only a single injection; (3) tissue distortion is rarely a problem, as solution is deposited away from the operative site; (4) intraoral injections can be less painful with use of topical anesthetic agents; (5) and patients may already be familiar with dental block injections.1 One disadvantage to the regional block is limited hemostasis. Local infiltration with a vasoconstrictor can be performed without pain after regional block. Factors influencing the choice of local anesthesia include the patient’s medical history, drug allergy, weight, area to be anesthetized, duration of anesthesia, and need for vasoconstriction. The 2 main classes of local anesthetics are ester and amide types. Esters are hydrolyzed by pseudocholinesterase in the plasma, whereas amides are predominantly metabolized in the liver.2 Impaired ability to metabolize an anesthetic should be considered in the decision. Patients with allergy to an ester type can be treated with an amide type. True allergic reaction to an amide is rare, and patients often report syncopal reactions as an allergy.3 Most local anesthetics are vasodilators. The addition of a vasoconstrictor offers several advantages including the following: (1) decreased blood flow to site of injection, (2) decreased absorption into bloodstream lessening likelihood of overdose, and (3) prolonged anesthesia by having higher concentrations around the nerve. 270
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIA/ THOMAS GLENN ISON
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIA/ THOMAS GLENN ISON
Lidocaine, an amide, is the most commonly used agent for dental anesthesia.1 It is available in a single-use dental cartridge (1.8 mL) as a 2% solution without vasoconstrictor, with 1:50,000 epinephrine, and with l:lOO,OOO epinephrine. Two percent lidocaine with l:lOO,OOO epinephrine can provide soft-tissue anesthesia lasting 3 to 4 hours2 Comparable anesthesia success has been reported for 2% lidocaine with 1:50,000 epinephrine and l:lOO,OOO epinephrine.4 The use of 2% lidocaine with 1:50,000 epinephrine is usually reserved for infiltration in which hemostasis is desired. Mepivacaine 3%, an amide, is often used in patients where vasoconstrictors are contraindicated. It provides 20 to 40 minutes of pulpal anesthesia and 2 to 3 hours of soft-tissue anesthesia. Bupivacaine 0.5% with 1:200,000 epinephrine is a long-acting amide that can be used for pain control after a procedure. Soft-tissue anesthesia can last 5 to 8 hours, but its onset (6 to 10 minutes) is slower than the other agents. The maximum dose of lidocaine and mepivacaine is 4.4 mg/kg; bupivacaine maximum dose is 1.3 mg/kg.2 Topical anesthetic agents are available to provide mucosal surface anesthesia before intraoral injection. Although the lidocaine solution can be used for topical anesthesia, concern arises over greater potential of toxicity from overdose. Dentists typically use flavored 20% benzocaine gels (Fig 1). Applied with a cotton-tipped applicator or cotton roll to dried oral mucosa, it provides surface anesthesia in 30 to 60 seconds, allowing for atraumatic needle penetration. The taste or sensation on the tongue may be unpleasant to young children and result in compliance problems. The dental syringe (Fig 1) is easily used for intraoral injections, although the standard syringe can be used. The thumb ring allows for l-hand
Figure I. Topical dental syringe.
anesthetic,
1.8 mL anesthetic
carpule, and
Figure 2. Facial area anesthetized
by infraorbital
271
nerve block.
aspiration, allowing the free hand to be used for retraction of tissues and stabilization of the patient. Single-use cartridges containing 1.8 mL of anesthetic are used. Twenty-five-, 27-, and 30-gauge, long (40 mm) and short (25 mm), needles are available and used according to personal preference. Pediatric dentists usually use the 30-gauge needle. The long needle should be used when deeper penetration of tissues is required, such as for inferior alveolar and infraorbital injections. Short needles are used for infiltration and nerve blocks in younger children.
lnfraorbital NerveBlock The infraorbital nerve is a terminal branch of the maxillary division of the trigeminal nerve. Extraorally, it provides sensory innervation to the lower eyelid, lateral nose, cheek, and upper lip, to the midline (Fig 2). Intraorally, it innervates the buccal and labial mucosa and gingiva, extending from the second primary molar (or second premolar in the permanent dentition) to the midline. The infraorbital foramen can be located by palpating the maxilla along a line extending from the supraorbital notch, pupil in forward gaze, and infraorbital notch of the orbital rim.5 Indication for this nerve block is the need for anesthesia of these soft tissues, such as in biopsy, debridement, or repair of lacerations of the cheek, lip, lower eyelid, or intraoral mucosa. In addition, diffusion of the anesthetic through the bone will block the anterior superior nerve, providing pulpal anesthesia to the canine and incisors. Bilateral blocks will provide complete anesthesia to the maxillary lip.
272
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIAI THOMAS GLENN ISON
Figure 3. Position of needle penetration tion.
for infraorbital
injec-
Technique Dry mucosa and place topical anesthetic in the depth of the labial vestibule just distal to the canine. Palpate the infraorbital foramen. Retract the lip, pulling the mucosa taut (Fig 3). Insertion is in the height of the vestibule just distal to the canine. Place the needle parallel to the long axis of the canine with the bevel facing the maxilla. Slowly advance the needle towards the foramen with the use of your finger as a guide. You may palpate the needle as it approaches the foramen. The needle should contact the superior rim of the foramen. Retract the needle from the periosteum and aspirate to ensure that a vessel has not been entered. Slowly inject 0.5 to 1.0 mL over the foramen (Fig 4). Success will be shown by anesthesia of the aforementioned soft tissues. Pulpal anesthesia of
Figure 5. Facial area anesthetized
by mental nerve block.
the incisors, canine, and primary molars (or permanent premolars) will also be obtained.
MentalNerveBlock
Figure 4. Needle position at infraorbital
foramen.
The mental nerve is a terminal branch of the mandibular division of the trigeminal nerve. Extraorally, it provides sensory innervation to the skin of the lower lip and chin from the commissure extending anteriorly to the midline (Fig 5). Intraorally, it innervates the alveolar mucosa, gingiva, and labial mucosa, extending anteriorly from the primary molar (premolar in older children) area to the midline. The mental foramen is located on the lateral aspect of the mandible, usually at the apices, between the primary molars (or premolars in older children) (Fig 6). The mental foramen can be located by palpating in the area of the primary molars. The mandible will feel smooth anterior and posterior to the foramen. Indication for this nerve
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIA/ THOMAS GLENN ISON
Figure 6. Mental foramen located in area of primary apices and position of needle for block.
273
molar
block is the need for anesthesia of these soft tissues such as in biopsy, debridement, or repair of lacerations of the lower lip or intraoral mucosa. Lacerations involving the commissure may also require buccal and infraorbital nerve blocks.
Technique Palpate the mental foramen. Dry the mucosa and place topical anesthetic in the depth of the vestibule in the area of the foramen. Retract the lip, pulling the tissue taut (Fig 7). With the bevel of the needle towards the bone, penetrate the mucosa slightly anterior to the foramen. Slowly advance the needle to the depth of the foramen. Aspirate. Slowly inject approximately 0.5 to 1.0 mL. Success will be shown by tingling of the lower lip.
BuccalNerveBlock The buccal nerve is a terminal branch of the mandibular division of the trigeminal nerve. It
Figure 8. Facial area anesthetized
by buccal nerve block.
crosses from the medial to the lateral aspect of the mandible, anterior to the ramus on a level of the occlusal plane. It provides sensory innervation to the skin of the cheek (Fig S), buccal mucosa, and gingiva in the molar area.
Technique Dry the mucosa of the buccal vestibule distal to the molars and apply topical anesthetic. Retract the cheek pulling the mucosa taut. Slowly penetrate the buccal vestibular mucosa, distal to the molars, until the periosteum is contacted (Fig 9). Aspirate. Slowly inject 0.5 mL. Tingling of the cheek will indicate success.
Inferior AlveolarNerveand LingualNerve
Figure 7. Mandibular lip retracted and position of needle for left mental nerve block.
The inferior alveolar nerve is a branch of the mandibular division of the trigeminal nerve. It is located in the pterygomandibular space lateral to the sphenomandibular ligament and medial to the ramus of the mandible. It enters the mandibular foramen, located in the middle to posterior third of the ramus (Fig 10). It provides sensory innervation to the buccal mucosa and gingiva anterior to the primary molars, skin of the chin, and lip. The lin-
274
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIAI THOMAS GLENN ISON
Figure 9. Injection site in mandibular buccal nerve block.
left posterior
vestibule for
gual nerve branches from the mandibular division of the trigeminal nerve and courses anteriorly and medially to the inferior alveolar nerve. It provides sensory innervation to the lingual gingiva, floor of the mouth, and anterior two thirds of the tongue to the midline. Anesthesia of the inferior alveolar nerve usually results in anesthesia to the lingual nerve. Indications for the inferior alveolar nerve block include the need for pulpal and soft-tissue (gingiva, labial mucosa, lower lip, and skin of chin) anesthesia, such as in debridement or repair of lacerations
Figure IO. Medial view showing right mandibular foramen in middle (anterior-posterior) of ramus. Needle positioned (from anterior) for inferior alveolar nerve block.
Figure I I. Syringe from penetrating the mucosa a left inferior alveolar positioned against the mandible.
right corner of mouth with the needle in the left pterygomandibular fossa for or lingual nerve block. The thumb is coronoid notch of the ramus of the
and treatment of odontogenic injuries. Bilateral inferior alveolar blocks are not usually recommended for younger children, as they may be prone to selfmutilation by biting the anesthetized lip or tongue because of loss of proprioception.
Technique To locate the site of injection, have the patient open the mouth wide. Place the thumb of the free hand, intraorally, on the coronoid notch, stretching the mucosa of the pterygomandibular triangle (Fig 11). Grasp the posterior border of the ramus with the forefinger. The line between the thumb and forefinger serves as the height of injection, with the midpoint being the antero-posterior target. Dry the mucosa and place topical anesthetic. The angle of needle insertion is from the opposite corner of the mouth, overlying the primary molars or premolars (Fig 12). Slowly advance the needle until bone is contacted. Move the barrel of the syringe slightly toward the midline, so that the needle parallels the ramus, and advance the tip to the foramen. Depth of insertion is usually between 1 to 2 cm, estimated by the midpoint of the thumb and finger position. Aspirate to ensure a vessel has not been entered. Slowly deposit 1.0 to 1.5 mL. To anesthetize the lingual nerve, withdraw the needle halfway. Aspirate. Slowly deposit 0.5 mL. Success will be noted by anesthesia of the lower lip and chin (mental nerve) for the inferior alveolar nerve and the lateral portion of the tongue for the lingual nerve. Lingualnerve anesthesia will occasionally be obtained with-
INTRAORAL NERVE BLOCKS FOR OROFACIAL ANESTHESIA / THOMAS GLENN ISON
275
Summary Orofacial anesthesia for biopsy, wound debridement, laceration repair, or treatment of odontogenie injuries can be easily obtained by intraoral nerve block. Dental injection techniques offer several advantages over local infiltration, including patient familiarity with the procedure. The practitioner should be knowledgeable of the anesthetic agent and prepared for any adverse reaction.
References
Figure 12. The path of insertion for an inferior alveolar or lingual nerve block has the barrel of the syringe overlying the opposite primary molars (or premolars in older patients).
out inferior alveolar anesthesia, indicating the block was placed too far anteriorly. The inferior alveolar nerve block is often missed also by injecting below the level of the mandibular foramen.
1. Kretzschmar JL, Peters JE: Kerve blocks for regional anesthesia of the face. Am Fam Physician 55:17011704, 1997. 2. Malamed SF: Handbook of Local Anesthesia. St Louis, MO, Mosby, 1986. 3. Panje WR: Local anesthesia of the face. J Dermatol Surg Oncol 5:311-3X, 1979. 4. Yared GM, Dagher FB: Evaluation of lidocaine in human inferior alveolar nerve block. J Endod 23:575578, 1997. 5. Zide BM, Swift R: How to block and tackle the face. Plas Reconstr Surg 101:840-851, 1998. 6. Trebus DL, Singh G, Meyer RD: Anatomical basis for inferior alveolar nerve block. Gen Dent 46:632-636, 1998.