Symptoms of anesthesia
- Mandibular teeth on one side become numb (via inferior alveolar nerve block)
- Lower lip and chin on one side become numb (via mental nerve block)
- Parts of the tongue and lingual gingival tissue on one side, except for the cheek side of the mandibular molars, become numb (via lingual nerve block)
- Tongue and floor of the mouth may experience harmless numbness and tingling (indicating lingual nerve anesthesia)
- Lingual shock may occur as the needle passes by the lingual nerve during administration
Injection techniques
- Inferior alveolar nerve block (IANB) is commonly used, approaching the nerve from the opposite side of the mouth over the contralateral premolars
- Gow-Gates technique involves directing the needle at the neck of the condyle just under the insertion of the lateral pterygoid muscle
- Vazirani-Akinosi technique is a closed-mouth injection technique, advancing the syringe parallel to the maxillary occlusal plane at the level of the maxillary mucogingival junction
- These techniques are used for extensive anesthesia or when the patient cannot open their mouth enough for the IANB
Complications
- Accidental self-inflicted trauma may occur after the procedure, such as biting the lip or tongue or thermal burn from drinking hot fluid
- Puncturing a blood vessel accidentally may cause a hematoma or blood blister that will heal over time
- Injection positioned too posteriorly may put anesthetic into the parotid gland, causing temporary facial paralysis
- Injection placed too medially may result in injection of the medial pterygoid muscle, leading to trismus
- Shallow injection may result in the sphenomandibular ligament acting as a barrier to the anesthetic, affecting only the lingual nerve
Additional information
- The inferior alveolar nerve block aims to anesthetize the inferior alveolar nerve before it enters the mandibular foramen on the medial surface of the mandibular ramus
- The long buccal nerve may not be anesthetized by an IANB, requiring a separate buccal nerve block for anesthesia of the buccal gingiva adjacent to the lower posterior teeth
- Lingual shock is a momentary symptom that may occur as the needle passes by the lingual nerve, causing an involuntary movement in the patient
- Needle tract infections of the pterygomandibular space can rarely occur due to inoculation of bacteria from the mouth during the injection
- The procedure can cause temporary numbness and tingling in the body of the tongue and floor of the mouth, indicating anesthesia of the lingual nerve
References
- Agur, Anne M.R., and Arthur F. Dalley. Grants Atlas Of Anatomy. 12th ed. Maryland, USA: Lippincott Williams & Wilkins, 2009.
- Aker, F. D. (2001). Blocking the buccal nerve using two methods of inferior alveolar block injection. Clinical Anatomy. 14 (2): 111–119.
- Illustrated Anatomy of the Head and Neck, Fehrenbach and Herring, Elsevier, 2012, page 216
- Meechan JG (January 1999). How to overcome failed local anesthesia. Br Dent J. 186 (1): 15–20.
- Local Anesthesia for the Dental Hygienist, Logothetis, Elsevier, 2012
Inferior alveolar nerve block (abbreviated to IANB, and also termed inferior alveolar nerve anesthesia or inferior dental block) is a nerve block technique which induces anesthesia (numbness) in the areas of the mouth and face innervated by one of the inferior alveolar nerves which are paired on the left and right side. These areas are the skin and mucous membranes of the lower lip, the skin of the chin, the lower teeth and the labial gingiva of the anterior teeth, all unilaterally to the midline of the side on which the block is administered. However, depending on technique, the long buccal nerve may not be anesthetized by an IANB and therefore an area of buccal gingiva adjacent to the lower posterior teeth will retain normal sensation unless that nerve is anesthetized separately, via a (long) buccal nerve block. The inferior alveolar nerve is a branch of the mandibular nerve, the third division of the trigeminal nerve. This procedure attempts to anaesthetise the inferior alveolar nerve prior to it entering the mandibular foramen on the medial surface of the mandibular ramus.[citation needed]
