The Gow-Gates Block Technique – how to lower jaw novocaine

I have many a times seen Dr. Dorfman patiently listen to the patient, while the patient is designing the shape of the porcelain crown for his anterior tooth on a piece of paper.

If a patient feels any pain during a procedure the treatment is stopped until all pain sensation is gone.  Patients will also be given control over the treatments they would like to get done during the visit. If a patient wants to have his teeth cleaned in two short appointments, he will be allowed to do so respectfully.

Dr. Dorfman suggests to wipe the area to be injected gently and apply the topical anesthetic on the dry tissue for 2 minutes.  If we need to work on the anterior tooth, he suggests to start injecting slightly posterior to the tooth, as the anterior area in the mouth is much more painful compared to the posterior area.  Carbocaine is used most of the times as its short acting.  Sometimes a combination of lidocaine and carbocaine is used to achieve effective anesthesia. After depositing the solution posterior to the tooth, slowly moving anteriorly through the deposited area, would tremendously help in achieving painless anesthesia for the anterior tooth.

The Gow-Gates block technique –

The Gow gates has many advantages over traditional Inferior Alveolar Nerve block. The path the needle traverses during a Gow Gates block technique contains much less muscle tissue than is traversed by the needle in a Inferior Alveolar  block, and thus there is little release of bradykinins which are the chemicals which cause the aching that patients feel when receiving a mandibular block.  Furthermore, the tissue through which the needle passes contains no nerve receptors, and thus there is little direct pain during the injection.  Patients usually remark that they felt no pain during the injection.

The area where the Gow-Gates is delivered is less vascularized than the area adjacent to the location of injection in a standard mandibular block.  Studies indicate that there is an 89-90% lower likelihood of giving an intra-vascular injection using this technique. In addition, because of the lower vascularization in the area, the anesthesia is less rapidly absorbed into adjacent blood vessels prolonging the presence of the anesthesia in the area, which means that mepivicaine without vasoconstrictor may be used to greater and longer lasting effect using the Gow-Gates.  Some users of this technique recommend that no vasoconstrictor be used at all.  The Gow-Gates technique anesthetizes the nerve trunk before it splits into its three main branches; the lingual branch, the buccal branch and the alveolar branch.  Thus a single shot does the work of three separate injections.

The success rate of the inferior alveolar nerve block is lower than for most other nerve blocks. Because of anatomical considerations in the mandible (primarily the density of bone), the administrator must accurately deposit local anesthetic solution to within 1 mm of the target nerve. The inferior alveolar nerve block has a significantly lower success rate because of two factors—(1) anatomical variation in the height of the mandibular foramen on the lingual side of the ramus and (2) the greater depth of soft-tissue penetration necessary—that consistently lead to greater inaccuracy. To achieve anesthesia of the mandibular molars, however, the inferior alveolar nerve must be anesthetized, and this frequently entails (with all its attendant disadvantages) a lower incidence of successful anesthesia. (Malamed, Stanley. Handbook of Local Anesthesia, 5th Edition. Mosby, 072004. 14).

The Gow-Gates mandibular nerve block is a true mandibular block injection because it provides regional anesthesia to virtually all the sensory branches of V3. In fact, the Gow-Gates may be thought of as a high inferior alveolar nerve block. When used, two beneficial effects are noted: (1) the problems associated with anatomical variations in the height of the mandibular foramen are obviated and (2) anesthesia of the other sensory branches of V3 (e.g., the lingual, buccal, and mylohyoid nerves) is usually obtained along with that of the inferior alveolar nerve. With proper adherence to protocol (and experience using this technique), a success rate in excess of 95% can be achieved. (Malamed, Stanley. Handbook of Local Anesthesia, 5th Edition. Mosby, 072004. 14).

S.S., NYU College of Dentistry

Categorised in: Dental Student Experiences

This post was written by Dr. Jeffrey Dorfman