Gow Gates Mandibular Nerve Block PDF

more slowly with this latter approach, its effectiveness is more 4. Lingual soft tissues and periosteum dramatic because patients who were previously difficult to 5. Body of the mandible, inferior porti Gow Gates Mandibular Nerve Block...

more slowly with this latter approach, its effectiveness is more 4. Lingual soft tissues and periosteum dramatic because patients who were previously difficult to 5. Body of the mandible, inferior porti Gow Gates Mandibular Nerve Block anesthetize now may be more easily managed. 6. Skin over the zygoma, posterior po The Gow-Gates mandibular nerve block has now been and temporal regions! “available” for approximately 45 years (since publication of the initial article in 197337). In a 2007 survey of Harvard School Indications of Dental Medicine graduates from 2000 through 2006, Other Common Names: Johnson et al.39 reported that between 3.7% and 16.1% of 1. Multiple procedures on mandibular Gow-Gates technique, thirdclinicians division trained in the Gow-Gates mandibular nerve block nerve block, V3 nerve block. technique used it as their primary mandibular technique and 2. When buccal soft tissue anesthesia, f to the midline, is necessary Nerves Anesthetized: Lingual soft tissue 1. Inferior alveolar nerve and bone 2. Mental nerve 3. Incisive nerve Tongue 4. Lingual nerve Alveolar 5. Mylohyoid nerve Mental mucous membrane 6. Auriculotemporal nerve foramen 7. Buccal nerve (in 75% of patients) Extraoral soft tissue Areas Anesthetized 1. Mandibular teeth to the midline Fig. 14.16 Area anesthetized by the Gow-Gates mandibular nerve block. 2. Buccal mucoperiosteum and mucous membranes on the side of injection 3. Anterior two-thirds of the tongue and floor of the oral cavity 4. Lingual soft tissues and periosteum 5. Body of the mandible, inferior portion of the ramus 6. Skin over the zygoma, posterior portion of the cheek, and temporal regions  Gow Gates Mandibular Nerve Block Indications: 1. Multiple procedures on mandibular teeth 2. When buccal soft tissue anesthesia, from the third molar to the midline, is necessary 3. When lingual soft tissue anesthesia is necessary 4. When a conventional IANB is unsuccessful Contraindications: 1. Infection or acute inflammation in the area of injection (rare) 2. Patients who might bite their lip or their tongue, such as young children and physically or mentally handicapped adults 3. Patients who are unable to open their mouth wide (e.g., trismus) Advantages: 1. Requires only one injection; a buccal nerve block is usually unnecessary (accessory innervation has been blocked) 2. High success rate (>95%), with experience 3. Minimum aspiration rate (∼2%) 4. Few postinjection complications (e.g., trismus) 5. Provides successful anesthesia where a bifid IAN and bifid mandibular canals are present  Gow Gates Mandibular Nerve Block Disadvantages 1. Lingual and lower-lip anesthesia is uncomfortable for many patients and is possibly dangerous for certain individuals. 2. The time to onset of anesthesia is somewhat longer than with an IANB, primarily because of the size of the nerve trunk being anesthetized and the distance of the nerve trunk from the deposition site (approximately 5 to 10 mm). 3. There is a learning curve with the Gow-Gates mandibular nerve block technique. Clinical experience is necessary to truly learn the technique and to fully take advantage of its greater success rate. This learning curve may prove frustrating for some persons. Positive Aspiration Approximately 2%. Gow Gates Mandibular Nerve Block Alternatives: 1. IANB and buccal nerve block 2. Vazirani-Akinosi closed-mouth mandibular block 3. Incisive nerve block: pulpal and buccal soft tissue anterior to the mental foramen 4. Mental nerve block: buccal soft tissue anterior to the first molar 5. Buccal nerve block: buccal soft tissue from the third to the mental foramen region 6. Supraperiosteal injection (infiltration): using (buffered) articaine hydrochloride, depositing 0.6 to 0.9 mL in the buccal fold adjacent to the tooth to be treated) 7. Intraosseous technique 8. PDL injection technique bifid palatal) of i. Height cusp of the maxillary injection second established molar (Fig.of by placement open his or her mouth wide for the duration of the 14.19A). the needle tip just below the mesiolingual (mesio- technique. The condyle then assumes a more frontal h fid Gow Gates Mandibular Nerve Block palatal) cusp of the maxillary second molar (Fig. 14.19A). position and is closer to the mandibular nerve trunk. c. Locate the extraoral landmarks: i. Intertragic notch. i ii. Corner of the mouth on the contralateral side. many d. Place your left index finger or thumb on the coronoid ls. notch; determination of the coronoid notch is not j than any nerve. nerve han k mm). rve bular rve ssary m). tage lar rove ary age ove Fig. 14.17 Target area for a Gow-Gates mandibular nerve block— neck of the condyle. A Fig. 14.17 Target area for a Gow-Gates mandibular nerve block— Corner of mouth neck of the condyle. nte- Corner of mouth first Tragus Intertragic te- notch d to rst Tragus ered) Intertragic L in notch B to (see Fig. 14.19 Intraoral landmarks for a Gow-Gates mandibular block. The tip of the needle is placed just below the mesiolingual cusp of the ed) ion) maxillary second molar (A) and is moved to a point just distal to the Fig. 14.18 Extraoral landmarks for a Gow-Gates mandibular nerve Fig in molar (B), maintaining the height established in the preceding step.  Gow Gates Mandibular Nerve Block Signs and Symptoms 1.Subjective: Tingling or numbness of the lower lip indicates anesthesia of the mental nerve, a terminal branch of the inferior alveolar nerve. It is also a good indication that the IAN may be anesthetized. 2.Subjective: Tingling or numbness of the tongue indicates anesthesia of the lingual nerve, a branch of the posterior division of the mandibular nerve. It is always present in a successful Gow-Gates mandibular nerve block. 3.Objective: use of a freezing spray (e.g., Endo-Ice) or an EPT with no response to maximal output (80/80) on two consecutive tests at least 2 minutes apart serves as a “guarantee” (∼99%) of successful pulpal anesthesia in nonpulpitic teeth. 4. Objective: no pain is felt during dental therapy.  Gow Gates Mandibular Nerve Block Safety Features 1. Needle contacting bone, thereby preventing over insertion. 2. Very low positive aspiration rate (2%); minimizes the risk of intravascular injection (the internal maxillary artery lies inferior to the injection site) Precautions If bone is not contacted, do not deposit any local anesthetic: 1. Withdraw the needle slightly. 2. Ask the patient to open his or her mouth wider. 3. Reinsert the needle. Make gentle contact with bone. 4. Withdraw the needle 1 mm and aspirate in two planes. 5. Inject if aspirations are negative.  Gow Gates Mandibular Nerve Block Failures of Anesthesia Rare with the Gow-Gates mandibular nerve block once the administrator has become familiar with the technique: 1. Too little volume. The greater diameter of the mandibular nerve may require a larger volume of anesthetic solution. Deposit up to 1.2 mL in a second injection if the depth of anesthesia is inadequate after the initial 1.8 mL. 2. Anatomic difficulties. Do not deposit anesthetic unless bone is contacted. Complications 1. Hematoma (