• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.4
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• pp.679-700
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• 1996

Inferior alveolar nerve dysfunction may be the result of trauma, disease, or iatrogenic injury. Inferior alveolar nerve injury is inherent risk in endodontic therapy, orthognathic surgery of the mandible, and extraction of mandibular teeth, particularly the third molars. The sensory disturbances of inferior alveolar nerve associated with such injury have been well documented clinical problem that is commonly evaluated by several clinical sensory test including Tinels sign, Von Frey test(static light touch detection), directional discrimination, two-point discrimination, pin pressure nociceptive discrimination, and thermal test. These methods used to detect and assess inferior alveolar nerve injury have been subjective in nature, relying on the cooperation of the patients. In addition, many of these techniques are sensitive to differences in the examiners experience and skill with the particular technique. Data obtained at different times or by different examiners are therefore difficult to compare. Prior experimental studies have used electro diagnostic methods(sensory evoked potential) to objectively evaluate inferior alveolar nerve after nerve injury. This study was designed with inferior alveolar nerve of rabbit. Several types of injury including mind, moderate, severe compression and perforation with 19 gauze, 21 gauze needle and 6mm, 10mm traction were applied for taking the sesory evoked ppterntial. Latency and amplitude of injury rabbit inferior alveolar nerve were investigated with sensory evoked potential using unpaired t-test. The results were as follows : 1. Intensity of threshold (T1) was $128{\pm}16{\mu}A$ : latency, $0.87{\pm}0.07$ microsecond : amplitude, $0.4{\pm}0.1{\mu}V$ : conduction velocity, 23.3 m/s in sensory evoked potential of uninjured rabbit inferior alveolar nerve. 2. Rabbit inferior alveolar nerve consists of type II and III sensory nerve fiber. 3. Latency was increased and amplitude was decreased in compression injury. The more injured, the more changed in latency and amplitude. 4. Findings in perforation injury was similar to compression injury. Waveform for sensory evoked potential improved by increasing postinjured time. 5. Increasing latency was prominent in traction injury rabbit inferior alveolar nerve. 6. In microscopic histopathological findings, significant degeneration and disorganization of the internal architecture were seen in nerve facicle of severe compression and 10mm traction group. From the above findings, electrophysiological assessment(sensory evoked potential) of rabbit injured inferior alveolar nerve is reliable technique in diagnosis and prognosis of nerve injury.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.25 no.4
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• pp.350-355
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• 1999

Purpose : The purpose of this study was 1) to find nerve damage after inferior alveolar nerve transposition and 2) to examine whether the soft tissue or bone changes around the nerve produce the compression to the nerve in the healing period. Materials and Method : Inferior alveolar nerve was exposed through the bony window and the scratch was made in the bone to be thought as the inferior alveolar canal. Suture was made after the nerve was repositioned. The nerve and surrounding tissues were examined with the light microscope and the fluorescent microscope before surgery and at 1 month, 3 months, and 5 months after surgery. Results : After surgery, the epineurium was damaged and the nerve was divided to several fascicles covered with the perineurium The newly formed fibrous connective tissue and vessels were seen around fascicles. There was new bone formation. However the nerve was not compressed by the connective tissue or the new bone. Conclusion : The results of this study suggest that neurosensory disturbances after inferior alveolar nerve transposition are resulted by the direct trauma in surgery rather than the compression to the nerve by the scar or new bone formation in the healing period.

• Journal of The Korean Dental Society of Anesthesiology
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• v.14 no.1
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• pp.3-10
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• 2014

The inferior alveolar nerve (IAN) block is the most frequently used mandibular injection technique for achieving local anesthesia for restorative and surgical procedures. However, The IAN block does not always result in successful anesthesia, especially pulpal anesthesia. Lidocaine is used as a "standard" local anesthetic for the inferior alveolar nerve. Articaine recently joined Korean market as a form of dental cartridge. It has an advantage of superior diffusion through bony tissue. A variety of trial was performed to improve the success rate of inferior alveolar nerve block. In this review, the recent update related with inferior alveolar nerve block anesthesia will be discussed on the anatomical consideration, anesthetic agent, technique, and complications.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.1
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• pp.1-6
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• 2002

When bilateral sagittal split ramus osteotomy or mandibular angle reduction are carried out, we have to consider the position of inferior alveolar nerve. For bone splitting or resection using a saw or an osteotome, the bucco-lingual position of the inferior alveolar nerve plays an important role in the preventing perioperative complications such as paresthesia or anesthesia. Because it is rare to find literatures concerning the mean anatomic position of the inferior alveolar nerve in Koreans, we investigated 30 patients who underwent to take CT and orthopantomogram for implant surgery, and evaluated the bucco-lingual position and vertical relationship of the inferior alveolar nerve at the mandible. The results showed that the distance between inferior alveolar nerve and buccal plate was the farthest at mandibular second molar ($7.1{\sim}7.4mm$) and the nearest at mandibular angle area ($4.4{\sim}4.8mm$). But it was no statistical relationship between the bucco-lingual postion of inferior alveolar nerve on the CT and its vertical position on the OPT. In conclusion, the results suggest that a careful surgical procedure is needed at the mandibular angle area to avoid a nerve damage and there are sufficient bone materials at the mandibular second molar are for bilateral sagittal split ramus osteotomy or mandibular angle reduction or plate fixation. And OPT is not usefull for the evaluation of a relative bucco-lingual position of inferior alveolar nerve in relation to its vertical postion on the OPT.

• Journal of Dental Anesthesia and Pain Medicine
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• v.15 no.2
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• pp.93-96
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• 2015

Although inferior alveolar nerve block is one of the most common procedures performed at dental clinics, complications or adverse effects can still occur. On rare occasions, ocular disturbances, such as diplopia, blurred vision, amaurosis, mydriasis, abnormal pupillary light reflex, retrobulbar pain, miosis, and enophthalmos, have also been reported after maxillary and mandibular anesthesia. Generally, these symptoms are temporary but they can be rather distressing to both patients and dental practitioners. Herein, we describe a case of diplopia caused by routine inferior alveolar nerve anesthesia, its related physiology, and management.

• The Journal of the Korean dental association
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• v.47 no.4
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• pp.211-224
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• 2009

This retrospective study was to analyze the inferior alveolar nerve and lingual nerve damage after the removal of mandibular third molars. In this questionnaire study, the subjects chosen for this study were 2472 dentists who answered the questionnaire about numbness after the extraction of lower third molars. The data collected by E-mail and web site included the incidence of removal of the lower third molars, the incidence and the experience of numbness of the inferior alveolar nerve and lingual nerve, rate and duration of recovery, the influence in day life after the long-term sensory loss, the period and amount of the indemnity in the case of medical dispute. The results are summarized as follows. 1. The experience rate and the incidence rate of the inferior alveolar nerve numbness by oral surgeons in the past year were19.9% and 0.14%. Those of the lingual nerve by oral surgeon were 7.7% and 0.05%.2. The experience rate and the incidence rate of the inferior alveolar nerve numbness by the dentists except oral surgeons in the past year were 9.7% and 0.19%. Those of the lingual nerve by the dentists except oral surgeons were 5.5% and 0.11%.3. The recovery rate of the inferior alveolar nerve after 1 year and 2 years were 85.6% and 91.3%. The recovery rate of the lingual nerve after 1 year and 2 years were 84.8% and 89.3%.In conclusion, most of numbness may be recovered within 2 years. However the possibility of long term and persistent numbness should not be neglected. Therefore practitioner must inform the possibility of nerve injury and include this possibility in the consent forms.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.3
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• pp.250-255
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• 1998

The purpose of this study was to evaluate the histologic change of the inferior alveolar nerve according to distraction amount following mandibular lengthening. Seven rabbits weighing about 2 kg were used. Corticotomy was performed on the mandibular body anterior to the right first premolar region and unilateral external fixation device was placed. Every effort was made to preserve the inferior alveolar nerve during the corticotomy. The rabbits were then allowed to heal for 7 days without distraction of the device. The mandible was lengthened 0.36 mm/day, 0.76 mm/day, or 1.0 mm/day. Corticotomy and lengthening of mandible were not performed in control group. After the completion of the lengthening process, a 14-day-consolidation period was allowed. After consolidation, rabbits were sacrificed, and histologic examination of the inferior alveolar nerve was performed. The results obtained were as follows : 1. In the control group, normal trifascicular pattern of inferior alveolar nerve was observed. Epineurium, perineurium, endoneurium, and axon with myelin sheath were observed in normal appearance. 2. In 0.36 mm/day distraction group, the trifascicular pattern was normally shown, and there was no destruction in epineurium, perineurium, and endoneurium. The mild changes including myelin attenuation, axoplasmic swelling and darkening were observed. 3. In 0.72 mm/day distraction group, it was possible to differentiate the epineurium from the perineurium. Two normal fascicles and one injuried fascicle were observed with a partially destructed perineurium. Most of the axons had axoplasmic swelling and darkening. 4. In 1 mm/day distraction group, it was difficult to differentiate the nerve structures such as fascicles, epineurium, perineurium, and endoneurium. The axons were severely destroyed, except few which showed decreases in size and changes in shape. Some collagen matrices were observed around the axons. These results suggest that the higher the distraction amount, the more severe the injury to the inferior alveolar nerve, fascicles, axons. Although distraction osteogenesis may be useful, the amount of distraction should be carefully selected.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.2
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• pp.173-178
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• 2021

Inferior alveolar nerve (IAN) injury is usually caused by stretching or crushing of the neurovascular structures and postoperative intra-alveolar hematoma or edema after dental procedures. This results in paresthesia in the ipsilateral chin, lip (vermilion border, skin, and mucosa), and labial or buccal alveolar mucosa of the mandibular anterior teeth. However, there are no reports of sensory alterations in the teeth, especially tooth hypersensitivity, after IAN injury. I report a case in which paresthesia of the lower lip and hypersensitivity of the lower anterior teeth occurred simultaneously after the removal of the third molar that was located close to the IAN. In addition, I discuss the reasons for the different sensory changes between the tooth and chin (skin) after nerve injury from a neurophysiological point of view. Since the dental pulp and periodontal apparatus are highly innervated by the inferior alveolar sensory neurons, it seems necessary to pay attention to the changes in tooth sensitivity if IAN injury occurs during dental procedures.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.5
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• pp.251-253
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• 2013

Inferior alveolar nerve block obtained maximum anesthetic effect using a small dose of local anesthetic agent, which also has low a complication incidence. Complications of an inferior alveolar nerve block include direct nerve damage, bleeding, trismus, temporary facial nerve palsy, and etc. Among them, the major iatrogenic complication is dental needle fracture. A fragment that disappears into the soft tissue would be hard to remove, giving rise to a legal problem. A 31-year-old woman was referred for the removal of a broken needle, following an inferior alveolar nerve block. Management involved the removal of the needle under local anesthesia with pre- and peri-operative computed tomography scans.

• Journal of Dental Anesthesia and Pain Medicine
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• v.17 no.2
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• pp.129-134
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• 2017

Efforts to apply augmented reality (AR) technology in the medical field include the introduction of AR techniques into dental practice. The present report introduces a simple method of applying AR during an inferior alveolar nerve block, a procedure commonly performed in dental clinics.