Numbness of the ear following inferior alveolar nerve block: the forgotten complication

Abstract

movement and appearance is affected when the CN V and VII are affected. 10,11 The following case reports of a distant complication that affects the auriculotemporal nerve after the administration of local anaesthetic using standard inferior alveolar nerve block technique. CASE REPORTA 30-year-old medically-fit Chinese female was given an appointment to have her mandibular left wisdom tooth removed under local anaesthesia after experiencing pericoronitis. She had experienced having her deciduous teeth removed without complications but never had any inferior alveolar nerve block before this.A standard inferior alveolar nerve block of two cartridges (4.4 mls) 2% lignocaine with 1:80,000 adrenaline was injected to the left mandible of the semi reclined patient, followed by surgical removal of the tooth without any diffi culty. Just before leaving the clinic, the patient informed the fi rst author that she still felt very numb around the left auricular area, especially the left external ear. Further questioning revealed that the left temporomandibuar joint, left auricle and part of her left temple were numb. Her description seemed to suggest that the area supplied by the left auriculotemporal nerve was blocked. This was confi rmed clinically with a pin prick test. She felt uncomfortable about this sensation, especially the feeling of 'fullness' in the external auditory meatus.The patient was assured that this altered sensation was short-lasting, and right

Proposed Classification of Auriculotemporal Nerve, Based on the Root System

“…Firstly, it is particularly important to predict the variability of ATN anatomy in the field of surgery involving the infratemporal fossa and dental anesthesia. Specifiaclly, correct recognition of these structures could prove highly advantageous in the surgical field [ 19 – 25 ] as well as demystifying possible side effects that occur during administration of local anesthesia to IAN [ 26 – 27 ]. Secondly, awareness of ATN anatomy seems to be particularly useful in understanding and explaining the mechanism of neuralgia [ 28 – 30 ] and migraine headaches [ 8 ].…”

Variations of Inferior Alveolar Nerve and Its Relation With Maxillary Artery in Infra Temporal Fossa

“…The same can be considered to explain the pain felt along the distribution of any of these branches without a reason as suggested by Siessere et al (2009). This may explain the temporary numbness of external ear and the region supplied by ATN as reported after IAN block by Ngeow & Chai (2009). It can explain the incomplete nerve block in dental anaesthesia or inadvertent effect on inltrating the local anaesthetic drug.…”

Periotic sensory dysfunction via postauricular approach after otitis media surgery

“…The phenomenon may be an anatomic and phylogenetic result of the highly variable and complicated branching pattern and forms of communications among periotic cutaneous sensory nerves distribution. Anatomically, the great auricular nerve was found to essentially connect with the parotid gland, mostly located inferior to the auricle or in the postauricular region, whereas the auriculotemporal nerve trunk provided more innervation to the skin of the upper half of the pinna and the anterior half of the external auditory meatus . Ryan and Fee found that the impairment of the great auricular nerve, demonstrated by the results of the sensory testing, was able to induce periotic sensory symptoms, particularly numbness, during parotidectomy .…”

“…Anatomically, the great auricular nerve was found to essentially connect with the parotid gland, mostly located inferior to the auricle or in the postauricular region, whereas the auriculotemporal nerve trunk provided more innervation to the skin of the upper half of the pinna and the anterior half of the external auditory meatus. 9,[12][13][14][15] Ryan and Fee found that the impairment of the great auricular nerve, demonstrated by the results of the sensory testing, was able to induce periotic sensory symptoms, particularly numbness, during parotidectomy. 6 And the study by Schmidt et al reported that the auriculotemporal nerve produced numbness, pain, or both in the temporomandibular joint region.…”