Mandibular Anesthesia Dr Lin 9-22-22.pdf

Pain Control I Techniques of Mandibular Anesthesia September 22, 2022 Euger Lin, DMD, FRCD(C) [email protected] Fellow, Royal College of Dentists of Canada Diplomate, American Board of Oral & Maxillofacial Surgeons Clinical Instructor, Boston University Goldman School of Dental Medicine Preparation o...

Pain Control I Techniques of Mandibular Anesthesia September 22, 2022 Euger Lin, DMD, FRCD(C) [email protected] Fellow, Royal College of Dentists of Canada Diplomate, American Board of Oral & Maxillofacial Surgeons Clinical Instructor, Boston University Goldman School of Dental Medicine Preparation of the Armamentarium Insertion of the cartridge Retract the piston Engage the harpoon Malamed Preparation of the Armamentarium Do not exert force on the plunger Screw needle Malamed ® Aspiject - by Septodont Self Aspirating Syringe Malamed Recapping and Cartridge Removal Scoop technique Remove the used cartridge Retract the piston Malamed Hand Position Palm up and finger rest: best control Palm down: poor control Palm up: better control Malamed Mandibular Anesthesia Inferior Alveolar Nerve Block 2. Incisive 3. Gow-Gates 4. Vazirani-Akinosi (closed mouth) 1. Soft Tissue Only 1. Mental 2. Buccal Case Presentation • A patient presents for the removal of an impacted tooth #32, which will require a soft tissue flap, removal of bone, and sectioning of the tooth. • Which local anesthetic technique would you perform to obtain adequate local anesthesia to perform the procedure? COMS 4th edition Technique • IAN Block with Long Buccal • Gow-Gates • Vazirani-Akinosi Inferior Alveolar Nerve Block • Nerves Anesthetized – Inferior alveolar • incisive • mental – Lingual (possibly) Malamed Areas Anesthetized • Mandibular teeth to midline • Body of the mandible, inferior portion of the ramus, buccal mucoperiosteum • Mucous membrane anterior to the mental foramen (mental nerve) • Anterior two thirds of the tongue and floor of the oral cavity (lingual nerve) • Lingual soft tissues and periosteum (lingual nerve) Evers, Haegerstam Indication - Procedures on multiple mandibular teeth in one quadrant - When buccal soft tissue anesthesia anterior to mental foramen is required (but there’s a better option) - When lingual soft tissue anesthesia is required (but there’s a better option) Evers, Haegerstam Contraindiations - Infection or acute inflammation in the area of injection - Patients who might bite lips or tongue (very young child, handicapped patient) - Limitation to open mouth (trismus) Case: Technique • You choose to perform an IAN with Long Buccal Technique: – What are the landmarks? Landmarks • Coronoid Notch • Pterygomandibular Raphe • The Occlusal Plane of the Mandibular Teeth • Contralateral Premolars Landmarks Coronoid Notch Pterygomandibular Raphe Landmarks OP of Mandibular Teeth Contralateral PM Inferior Alveolar Nerve Block Right Left Face patient, sit 8 o’clock Face same direction, sit 10 o’clock Malamed Case Presentation- Complication • After administering LA, the patient develops a left sided facial paralysis? • What happened? • You did not make bone contact, so… IAN Complication • The parotid gland is closely related to the mandible. • If the needle is too deep, local anesthetic solution could be injected within the parotid gland near CN 7. • Transient blockade (paralysis) CN III and VII – Eye Opening and Closure • CN III – Innervates LPS – Opens eyes • CN VII – Innervates O – Closes eyes You recognize bone contact was not made… • Overinsertion … so retract and reposition the syringe medially and the needle will go laterally If you do not obtain adequate LA with the IAN Block, what could be the cause? If you do not obtain adequate LA with the IAN Block, what could be the cause? • Injection too low (most common) If you do not obtain adequate LA with the IAN Block, what could be the cause? • Injection too far anterior If you do not obtain adequate LA with the IAN Block, what could be the cause? • Accessory innervation – Which nerve is involved? How do you correct this? How do you correct: a low injection? • Correct by reinjecting 5 to 10mm above the previous site How do you correct: an anterior injection? • Retract and reposition the syringe laterally and the needle will go medially, then advance posteriorly How do you correct: accessory innervation? • Correct by: - Lingual infiltrate (mylohyoid nerve) PDL Inject lower/higher? for a Bifid IAN Inject below incisors with inadequate LA (from overlapping contralateral IAN) Disadvantages • • • • Wide area of anesthesia Rate of inadequate anesthesia (31% - 81%) Intraoral landmarks not consistently reliable Positive aspiration: 10 – 15%, highest of all intraoral injection techniques • Lingual and lower lip anesthesia, which may be discomforting to many patients • Partial anesthesia where a bidfid IAN and bidfid mandibular canals are present; cross-innervation in lower anterior region Disadvantages • • • • Wide area of anesthesia Rate of inadequate anesthesia (31% - 81%) Intraoral landmarks not consistently reliable Positive aspiration: 10 – 15%, highest of all intraoral injection techniques • Lingual and lower lip anesthesia, which may be discomforting to many patients • Partial anesthesia where a bifid IAN and bifid mandibular canals are present; cross-innervation in lower anterior region Bifid IAN Incisive Nerve Block • A terminal branch of the IAN • Travels in incisive canal as a terminal branch of the IAN • Always anesthetized with a successful IAN • Lingual soft tissue are not anesthetized Incisive Nerve Block • Nerve anesthetized – mental and incisive • Areas anesthetized – buccal mucous membrane anterior to the mental foramen to the mid line and the skin of chin and the lower lip – pulpal nerve fibers to the premolars, canine and incisors Malamed Incisive Nerve Block • Indications – pulpal anesthesia on mandibular teeth anterior to the mental foramen – When IAN block is not indicated and when multiple anterior teeth are treated Malamed Incisive Nerve Block • Contraindications: Infection or acute inflammation in the area of injection • Advantages: Provides pulpal anesthesia without lingual anesthesia, High success rate • Disadvantages: – Does not provide lingual anesthesia – Partial anesthesia may develop at the midline because nerve fiber overlap with the opposite side (rare) • Positive Aspiration: 5.7% Back to the case… After the successful IAN block, you make your soft tissue incision and the patient feels pain. What happened? Buccal Nerve Block • Nerve anesthetized – buccal nerve • Area anesthetized – soft tissues and periosteum buccal to the mandibular molar teeth Evers, Haegerstam Buccal Nerve Block • Indications – when buccal soft tissue anesthesia is required for dental procedures in the mandibular molar region Malamed Buccal Nerve Block • Contraindication: Infection or acute inflammation in the area of injection • Advantages: – High success rate – Technically straightforward • Disadvantages: Potential for pain if the needle contacts the periosteum • Positive Aspiration: 0.7% Gow-Gates Mandibular Nerve Block • A true mandibular nerve block • Nerves Anesthetized • • • • • • • Evers, Haegerstam inferior alveolar lingual mylohyoid mental incisive auriculotemporal buccal (in 75% of patients) Gow-Gates Mandibular Nerve Block • Indication – multiple procedures on mandibular teeth – When buccal soft tissue anesthesia is needed from the third molar to the midline – When lingual soft tissue anesthesia is needed – When a conventional IAN block is unsuccessful Gow-Gates Mandibular Nerve Block • Area of insertion: mucous membrane on mesial of the ramus • Line from the intertragic notch to the corner of the mouth Malamed Gow-Gates Mandibular Nerve Block • Target area: Condylar neck just below the insertion of the lateral pterygoid muscle • Height: Just below maxillay ML cusp of the 2nd molar • Site: Penetrate just distal to the maxillary 2nd molar Malamed Gow-Gates Mandibular Nerve Block • Areas Anesthetized: – – – – – – Mandibular teeth to the midline Buccal mucoperiosteum and mucous membranes on the side of injection Anterior two thirds of the tongue and floor of the oral cavity Lingual soft tissues and periosteum Body of the mandible, inferior portion of the ramus Skin over the zygoma, posterior portion of the cheek, and temporal region Gow-Gates Mandibular Nerve Block • Contraindications: – Infection or acute inflammation in the area of injection – Patients who might bite their lip or their tongue – Patients who are unable to open their mouth wide Gow-Gates Mandibular Nerve Block • Advantages: – Requires only one injection – High success rate (>95%) with experience – Minimum aspiration rate: 2% – Few postoperative complications – Provides successful anesthesia where a bidfid IAN and bifid mandibular canals are present Gow-Gates Mandibular Nerve Block • Disadvantages: – Lingual and lower lip anesthesia is uncomfortable for many patients – The time of onset of anesthesia is somewhat longer than with the IANB, primarily due to the size of the nerve trunk and the distance of the nerve trunk from the deposition site – There is a learning curve with the technique Gow-Gates Mandibular Nerve Block • Complications: – Hematoma (<2% incidence of aspiration) – Trismus (extremely rare) – Temporary paralysis of CN III, IV, VI : • Diplopia, ipsilateral blepharoptosis and eye paralysis • Origins of the Middle Meningeal and Inferior Alveolar arteries are in close proximity to each other. By way of the arterial system, solution may gain access to the cavernous sinus via the MMA intracranial terminal branches. Cavernous Sinus - OTOMCAT O O T A C A T O O M M Case Presentation • A patient cannot open their mouth due to trismus. • Which local anesthetic technique would you perform? Vazirani-Akinosi Closed Mouth Block • Nerves Anesthetized – – – – – Malamed inferior alveolar incisive mental lingual mylohyoid Vazirani-Akinosi Closed Mouth Block • Areas Anesthetized – mandibular teeth to the midline – body of the mandible and inferior portion of the ramus – buccal mucoperiosteum and mucous membrane in front of the mental foramen – Anterior two thirds of the tongue and the floor of the mouth – lingual soft tissues and periosteum (lingual nerve) Malamed Vazirani-Akinosi Closed Mouth Block • Indications – limited mandibular opening – Inability to visualize IANB landmarks • Contraindications – Infection, acute inflammation – Patients who may bite themselves – Inability to visualize or gain access to lingual aspect of the ramus http://www.bdj.co.uk./archives/1999/v186n1/full_text/bdj0006.sht ml#FIGS Vazirani-Akinosi - Technique • Area of Insertion: - Mandibular medial soft tissue - Adjacent to maxillary tuberosity - Height of the MGJ adjacent to the 3M Vazirani-Akinosi Closed Mouth Block • Advantages: – Relatively atraumatic – Patient need not be able to open the mouth – Fewer postoperative complications – Lower aspiration rate (<10%) than with the inferior alveolar nerve block (10-15%) – Provides successful anesthesia where a bifid IAN and bifid mandibular canals are present Vazirani-Akinosi Closed Mouth Block • Disadvantages: – Difficult to visualize the path of the needle and the depth of insertion – No bony contact; depth of penetration somewhat arbitrary – Potentially traumatic if the needle is too close to the periosteum Case Presentation • A patient requires a soft tissue biopsy of the lower lip for a lesion adjacent to tooth #26. • Which techniques would you use, and why? Mental Nerve Block • Indication -soft tissue biopsies and suturing • Nerve anesthetized - mental nerve, a terminal branch of the inferior alveolar nerve Malamed Mental Nerve Block • Area anesthetized – buccal mucous membrane anterior to the mental foramen to the mid line and the skin of the lower lip Malamed Mental Nerve Block • Contraindications: Infection or acute inflammation in the area of injection • Advantages: – High success rate – Technically straightforward – Usually entirely atraumatic • Disadvantage: – Hematoma • Positive Aspiration: 5.7% Mandibular Anesthesia- Review Inferior Alveolar Nerve Block 2. Incisive 3. Gow-Gates 4. Vazirani-Akinosi (closed mouth) 1. Soft Tissue Only 1. Mental 2. Buccal Case Presentation • 55 y.o. male with PMH significant for MI three years ago, presents to your office for treatment of a painful lower right (#32) third molar. • Physical Exam: Tooth # 32 large decay below the gingival margin. Tooth is deemed non-restorable and needs to be surgically extracted. • You determine that a surgical extraction is required. • What local anesthesia can you use? a) Lidocaine (Xylocaine) b) Articaine (Septocaine) c) Bupivacaine (Marcaine) d) Mepivacaine (Carbocaine) 2% Lidocaine with 1:100000 epinephrine • What is the amount of local anesthesia in one carpule? • What is the limit of local anesthesia? • What is the amount of vasoconstrictor in one carpule? • What is the limit of vasoconstrictor for a cardiac patient? 2% Lidocaine … 20 mg/ml • 2% Lidocaine is… 20mg/ml of Lidocaine • Trick • 2%...take away the % then add a zero ( or multiple by 10) • 1% = 10mg/ml • 2% = 20mg/ml • 10%= 100mg/ml 2% Lidocaine … 20 mg/ml • 2% = 2g/100ml • 2g/100ml = 2000mg/100ml • 2000mg/100ml= 20mg/ml 1:100000 Epinephrine … 0.01 mg/ml • 1:100000 = 1g/100000ml • 1g/10000ml = 1000mg/100000ml • 1000mg/100000ml = 1mg/100ml • 1mg/100ml = 0.01 mg/ml 2% Lidocaine with 1:100000 epinephrine • 2% is 20mg/ml of Lidocaine 1:100k is 0.01mg/ml of epinephrine • Each cartridge is 1.7ml… so each has 34mg of Lidocaine Each cartridge is 1.7ml… so each has 0.017mg of Epi • Limit for Lido is 4.4 mg/kg… for Lido with Epi is 7mg/kg Guideline for cardiac patients… limit epinephrine to 0.04mg • A 70kg patient can have >10 but stay conservative with less 2 cartridges What injection technique would you use? 1. IAN Mandibular Block 2. Buccal Nerve Block Triangulate 3 Hard Tissue Landmarks 1. Coronoid Notch 2. Mandibular Angle 3. Posterior Condyle The center approximates the mandibular foramen Triangulate 3 Soft Tissue Landmarks 1. The buccal tissues (mandible) 2. Lateral Ptyerogoid 3. PMR (Medial Pterygoid) The center approximates the mandibular foramen Evers, Haegerstam Visualize and Overlay these 2 Triangles Find the depression and insert into the pterygomandibular space Dr. Lin’s Pearls for an IAN Block • • • • • • Position patient and yourself. Don’t shake…it’s more distracting. Topical…Does it work? Nah..but do it because patients expect it. TRIANGULATE 3 hard tissue and 3 soft tissue landmarks. Use the long 27 gauge needle. Deposit a small amount first…wait 20-30 seconds, tell patient they should not feel it as much, then complete. • Deposit remainder of the cartridge slowly…minimize tissue distension. Do Your Best and Forget the Rest - Tony Horton, P90X, Power Nation