Gow-Gates Mandibular Nerve Block Overview

Gow-Gates Mandibular Nerve Block

• The Gow-Gates mandibular nerve block has been used for 45 years.

• The Gow-Gates technique is a primary mandibular anesthetic technique that involves blocking the mandibular nerve, along with several other branches.

• Nerves anesthetized by the Gow-Gates mandibular nerve block:

  • Inferior Alveolar Nerve
  • Mental Nerve
  • Incisive Nerve
  • Lingual Nerve
  • Mylohyoid Nerve
  • Auriculotemporal Nerve
  • Buccal Nerve (in 75% of patients)

• Areas anesthetized by the Gow-Gates mandibular nerve block:

  • 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 regions

Indications for Gow-Gates Mandibular Nerve Block

• Multiple procedures on mandibular teeth
• When buccal soft tissue anesthesia, from the third molar to the midline, is necessary
• When lingual soft tissue anesthesia is necessary
• When a conventional IANB is unsuccessful

Contraindications for Gow-Gates Mandibular Nerve Block

• Infection or acute inflammation in the area of injection (rare)
• Patients who might bite their lip or their tongue, such as young children and physically or mentally handicapped adults
• Patients who are unable to open their mouth wide (e.g., trismus)

Advantages of Gow-Gates Mandibular Nerve Block

• Requires only one injection; a buccal nerve block is usually unnecessary
• High success rate (>95%) with experience
• Low aspiration rate (∼2%)
• Few post-injection complications (e.g., trismus)
• Provides successful anesthesia where a bifid IAN and bifid mandibular canals are present

Disadvantages of Gow-Gates Mandibular Nerve Block

• Lingual and lower-lip anesthesia is uncomfortable for many patients and possibly dangerous for certain individuals.
• The time to onset of anesthesia is somewhat longer than with an IANB 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).
• There is a learning curve with the Gow-Gates mandibular nerve block technique.

Alternatives to Gow-Gates Mandibular Nerve Block

• IANB and buccal nerve block
• Vazirani-Akinosi closed-mouth mandibular block
• Incisive nerve block
• Mental nerve block
• Buccal nerve block
• Supraperiosteal injection
• Intraosseous technique
• PDL injection technique

Gow-Gates Mandibular Nerve Block Technique

• The patient should open their mouth wide.
• Locate the extraoral landmarks:
  • Intertragic notch
  • Corner of the mouth on the contralateral side.
• Place your left index finger or thumb on the coronoid notch.
• Locate the intraoral landmarks:
  • First step: Place the needle tip just below the mesiolingual (mesio-palatal) cusp of the maxillary second molar.
  • Second step: Move the needle to a point just distal to the mesiolingual (mesio-palatal) cusp of the maxillary second molar, maintaining the height established in the preceding step.

Signs and Symptoms of Successful Gow-Gates Mandibular Nerve Block

• Subjective: Tingling or numbness of the lower lip indicates anesthesia of the mental nerve
• Subjective: Tingling or numbness of the tongue indicates anesthesia of the lingual nerve
• Objective: The 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 of successful pulpal anesthesia in nonpulpitic teeth.
• Objective: No pain is felt during dental therapy.

Safety Features of Gow-Gates Mandibular Nerve Block

• Needle contacting bone prevents over insertion.
• Low positive aspiration rate (2%) minimizes the risk of intravascular injection.

Precautions of Gow-Gates Mandibular Nerve Block

• If bone is not contacted, do not deposit any local anesthetic:
  • Withdraw the needle slightly.
  • Ask the patient to open his or her mouth wider.
  • Reinsert the needle. Make gentle contact with bone.
  • Withdraw the needle 1 mm and aspirate in two planes.
  • Inject if aspirations are negative.

Explore the Gow-Gates mandibular nerve block, a primary anesthetic technique used for over 45 years. This quiz covers the nerves and areas anesthetized, along with its clinical indications. Enhance your understanding of this essential procedure in dental anesthesia.