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Sympathetic nerve system has been proved to have important regulative effects to bone mass. However, the role of sympathetic nerve system in distraction osteogenesis (DO) is unclear. Here we show that the sympathetic nerve system plays an important role in mandibular DO. Thirty male Sprague-Dawley rats were divided into 2 groups at random. Right-side mandibular DO was performed on the 15 rats in control group (group A). Bilateral transection of cervical sympathetic trunk and right-side mandibular DO were performed on the 15 rats in the experimental group (group B). After operation, quantitative general observations, micro-computed tomography bone morphology analysis, and hematoxylin-eosin staining osseous tissue on new osteotylus in distraction gap were performed at consolidation time of 1, 14, and 28 days. SPSS 12.0 software package was used for statistical analysis. At 1 and 14 days of consolidation time, there was more continuous bone formation in the experimental group than that of the control group as determined by gross observation. Bone formation parameters including bone mineral density, bone volume-total volume ratio, bone trabeculae number as determined by micro-CT, and histological study of the test group were significantly higher than those of the control group (P < 0.05). No significant difference was noted between the 2 groups on consolidation time of 28 days. Our study suggested that the sympathetic innervation loss could improve mandibular DO and new bone formation, and the sympathetic nerve system might negatively regulate the process of DO.

Background: Pre-implant placement posterior mandibular bone grafts remain a challenge for maxillofacial surgeons. We present a coffering technique we prefer using in this localization., Surgical Procedure: This original technique involves creating a sagittal mandibular groove in which a graft harvested from the retromolar region is wedged vertically, after being sharpened in a bone mill. Reconstruction of the alveolar region itself is achieved by filling up the space between this vestibular coffer and the residual alveolar ridge with particulate bone graft from the bone mill., Results: A hundred patients were operated with this technique by the same team from 2005 to 2010. The treatment failed for four patients at 3 post-operative months. No alteration of inferior alveolar nerve was observed., Discussion: This coffering technique seems to be fully adequate in case of a posterior mandibular atrophy with a narrow ridge and sufficient bone height. This technique has several assets. Guided bone regeneration is associated with the use of exclusively autologous bone grafts. It may be performed under local anesthesia. The donor site is close, and the regenerated bone is of good quality. Implant placement must be achieved from 4 to 6 months after graft surgery. The drawbacks of the technique are related to donor site possibilities, and to the alveolar ridge height. Morbidity is low., (Copyright © 2012. Published by Elsevier Masson SAS.)

The aim of this study was to elucidate the exact location of the mandibular branch of the facial nerve according to different neck positions. Twenty-two hemifaces of 11 fresh human cadavers were used (age range, 53-89 y; mean age, 72.3 ± 10.5 y; 8 men and 3 women). Working through skin windows, the distance from the mandibular border to the mandibular branch of the facial nerve (border-nerve distance or BND) was measured at 3 points: (1) the mandible angle (gonion or Go point), (2) the point where the mandibular branch of the facial nerve crosses the facial artery (FA point), and (3) the one-fourth point from the gonion to the menton (1/4 point). Threads were hung on the skin windows along the mandibular border. With the neck in the neutral position and then full flexion (15 degrees), extension (15 degrees), and left and right rotations (30 degrees), the distance of the mandibular branch from the thread of the mandibular border was measured using calipers. In the neutral position, the mandibular branch was 3.50 ± 2.82 mm above the mandibular border at the Go point, 5.34 ± 2.98 mm above the mandibular border at the FA point, and 5.28 ± 1.86 mm above the mandibular border at the 1/4 point. At all 3 points, flexion or extension of the neck did not significantly move the mandibular branch. At the Go point and FA point, there was no significant difference between the ipsilateral rotation position and the contralateral rotation. Yet at the 1/4 point, the BND decreased (4.32 ± 2.60 mm) with the neck in ipsilateral rotation and the BND increased (5.97 ± 2.62 mm) with the neck in contralateral rotation. There was a significant difference between the ipsilateral rotation position and the contralateral rotation position (P = 0.020, t-test). Surgeons should keep in mind that at the 1/4 point, the mandibular branch of the facial nerve moves downward 1.10 ± 1.42 mm with the neck in ipsilateral rotation and moves upward 0.49 ± 1.84 mm with the neck in contralateral rotation.

The inferior alveolar nerve remains an anatomical obstacle for implant insertion in the posterior part of the mandible. Inferior alveolar nerve lateralisation allows new implant-borne prosthetic alternatives, after a careful radiological check-up and for an adapted prosthetic project, for removable and fixed prostheses. We present the infra-alveolar nerve lateralisation technique, its indications and contra-indications. This technique completes the armamentarium of surgical techniques for the correction of inferior molar edentulism., (Copyright © 2012. Published by Elsevier Masson SAS.)

Objectives: To examine the relationship between the anatomical position and the bone quality of the inferior alveolar nerve (IFAN) canal and long-term neurosensory disturbance (NSD) of the IFAN after a sagittal split ramus osteotomy (SSRO)., Material and Methods: CT images were taken of patients with mandibular prognathism. The location of the IFAN and the bone density around the IFAN were measured on CT images. Whether NSD at 6 months and 1 year after SSRO was related to the position and bone quality of the IFAN canal was analyzed., Results: Significant correlations were found between the anatomical position and the bone quality of the IFAN canal and the period to the resolution of NSD of the IFAN from 3 months to 1 year after SSRO. If the HU values around the IFAN were greater than 300 HU and/or the distance from the buccal aspect of the IFAN canal to the outer buccal cortical margin was less than 6 mm, NSD of the IFAN at 1 year after SSRO was significantly increased., Conclusion: It is important to pay particular attention to the anatomical position of the IFAN and the bone quality around the IFAN to predict long-term NSD of the IFAN after SSRO., (Copyright © 2011 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Background: The incidence of implant-related inferior alveolar nerve injuries (IANI) is steadily increasing within the UK population., Aims: This study prospectively reviewed thirty cases (35% male; 65% female) of implant-related IANI seen in a specialist nerve injury clinic.Methods Neurosensory examinations were carried out to ascertain a quantifiable rating of the perception, pain profiling and functional difficulties. Data were analysed using SPSS software., Results: Patients were aware of signing consent forms for the surgery in 11 cases and 8 of those felt they were not explicitly warned about nerve injury. Over 70% of patients were referred after six months post injury. Implant surgery planning involved intra-oral films only (30%), CBCT (10%), dental pantomograph (50%) and long cone peri-apical radiographs (48%). However, no radiographic evidence pre- or postoperatively was provided by the referring practitioner in 15% of cases. Intra-operative problems included bleeding and neurological symptoms. Proximity of the implant bed or implant to the inferior alveolar canal was evident radiographically. This showed contact with roof inferior alveolar nerve canal in 44% of cases, protrusion into the canal in 20% of cases, crossing of the canal in 20% cases and distance in one case, presumed to be due to local anaesthetic injury. All patients presented with a demonstrable neuropathy, which included neuropathic pain (50%) that interfered with speaking, kissing and socialising., Conclusions: Consent, preoperative planning and appropriate referral were inadequate in provision of mandibular implants in this patient group. Recommendations have been proposed to improve practice and possible novel strategies are suggested for the prevention and improved management of these complications.

Objective: Loss of teeth is accompanied with loss of function and therefore reduction of alveolar bone height. Insufficient bone height can jeopardize the anchorage of implants or surgical procedures such as distraction osteogenesis, because of possible mandibular nerve damage. The goal of this investigation was to determine the exact course of the intramandibular nerve in edentulous mandibles., Material and Method: The study samples included 37 dry human edentulous mandibles. A dental CT scan analysis was performed and four cross sectional views were investigated for each mandible. The Cawood classification was used to assess the grade of atrophy. Implantation simulation was performed in every case., Results: There was no bilateral symmetry in edentulous mandibles, whatever the cross-section studied. A rate of 38.7% were classified Cawood class IV, the most common group in edentulous patients. Our study results led us to place the distraction osteogenesis device in the posterior edentulous mandible. Implant placement was not possible in every case., Discussion: Our findings allow better understanding from the pathway of the mandibular canal close to the first and second molar in edentulous mandibles. This anatomical data and surgical techniques such as implant insertion and distraction osteogenesis allow finding solutions for "mandibular edentulism". Distraction is essential for a successful implantology., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

Bone remodeling, the mechanism that modulates bone mass adaptation, is controlled by the sympathetic nervous system through the catecholaminergic pathway. However, resorption in the mandible periosteum envelope is associated with cholinergic Vasoactive Intestinal Peptide (VIP)-positive nerve fibers sensitive to sympathetic neurotoxics, suggesting that different sympathetic pathways may control distinct bone envelopes. In this study, we assessed the role of distinct sympathetic pathways on rat femur and mandible envelopes. To this goal, adult male Wistar rats were chemically sympathectomized or treated with agonists/antagonists of the catecholaminergic and cholinergic pathways; femora and mandibles were sampled. Histomorphometric analysis showed that sympathectomy decreased the number of preosteoclasts and RANKL-expressing osteoblasts in mandible periosteum but had no effect on femur trabecular bone. In contrast, pharmacological stimulation or repression of the catecholaminergic cell receptors impacted the femur trabecular bone and mandible endosteal retromolar zone. VIP treatment of sympathectomized rats rescued the disturbances of the mandible periosteum and alveolar wall whereas the cholinergic pathway had no effect on the catecholaminergic-dependent envelopes. We also found that VIP receptor-1 was weakly expressed in periosteal osteoblasts in the mandible and was increased by VIP treatment, whereas osteoblasts of the retromolar envelope that was innervated only by tyrosine hydroxylase-immunoreactive fibers, constitutively expressed beta-2 adrenergic receptors. These data highlight the complexity of the sympathetic control of bone metabolism. Both the embryological origin of the bone (endochondral for the femur, membranous for the mandibular periosteum and the socket wall) and environmental factors specific to the innervated envelope may influence the phenotype of the sympathetic innervation. We suggest that an origin-dependent imprint of bone cells through osteoblast-nerve interactions determines the type of autonomous system innervating a particular bone envelope., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Context: It was suggested that the accessory neurovascular foramina of the mandible might be of significance in relation to the effectiveness of local anesthesia following the routine inferior alveolar nerve block., Aims: To investigate the incidence of neurovascular foramina over the lingual surface of the mandible in South Indian population., Settings and Design: The study was conducted at the department of anatomy., Materials and Methods: The study included 67 human adult dry mandibles, the exact ages and sexes of which were not known. The location and number of neurovascular foramina were topographically analyzed., Statistical Analysis Used: Descriptive statistics., Results: The foramina were observed in 64 mandibles (95.5%) and were often multiple in most of the cases. They were located between the two medial incisors in 8 mandibles (1.9%), between the medial and lateral incisor in 34 mandibles (50.7%; 25-bilateral; 7-right; 2-left), between the lateral incisor and canine in 7 mandibles (10.4%; 2-bilateral; 3-right; 2-left), between the canine and first premolar in 6 cases (8.9%; 3 on each side). Foramina were also present around the genial tubercle in 56 mandibles (83.6%). Among them, 52 mandibles showed a single foramen just above the genial tubercle, 34 mandibles had foramina below the tubercles, 13 mandibles had foramina on the right side of genial tubercle and 17 were having on the left side., Conclusion: Since the anatomical details of these foramina are important to various fields of dentistry and oncology, the present investigation was undertaken. The clinical significance and implications are emphasized.

Purpose: Coronectomy is performed when contact between the mandibular third molar apex and the inferior alveolar nerve is suspected. The efficacy of coronectomy compared with conventional tooth extraction has been recognized in recent years. However, few studies have reported the postoperative prognosis of roots remaining in the bone or surrounding tissue. Therefore, a clinical evaluation was performed with dental computed tomographic imaging of the coronectomy sites 1 year after the procedure., Patients and Methods: This study investigated 101 patients (116 teeth) who underwent a coronectomy from March 2006 through December 2009. They were recalled 1 year later for a clinical evaluation and dental computed tomographic imaging of the coronectomy sites. The clinical evaluation was based on palpation and macroscopic findings., Results: In 99.2% (115 teeth) of the studied cases, the soft tissue distal to the mandibular second molar was healthy and the retained roots were covered by bone. In 1 case (0.8%), an eruption of roots into the oral cavity was observed; however, no inflammation was observed in the nearby soft tissue. In all 116 teeth, no transmission images indicative of periapical lesions, which usually result from necrosis of the pulp, were observed in the apical area of the retained roots., Conclusions: The absence of transmission images indicative of periapical lesions and the presence of bone covering more than 99.2% (115 teeth) of the retained roots showed a safe postoperative course at the 1-year follow-up after coronectomy., (Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

The neurovascular bundle may be vulnerable during surgical procedures involving the mandible, especially when anatomical variations are present. Increased demand of implant surgeries, wider availability of three-dimensional exams, and lack of clear definitions in the literature indicate that features of anatomical variations should be revisited. The objective of the study was to evaluate features of anatomical variations related to mandibular canal (MC), such as bifid canals, anterior loop of mental nerve, and corticalization of MC. Additionally, bone trabeculation at the submandibular gland fossa region (SGF) was assessed and related to visibility of MC. Cone beam computed tomography exams from 100 patients (200 hemimandibles) were analyzed and the following parameters were registered: diameter and corticalization of MC; trabeculation in SGF region; presence of bifid MC, position of bifurcations, diameter, and direction of bifid canals; and measurement of anterior loops by two methods. Corticalization of the MC was observed in 59% of hemimandibles. In 23%, MC could be identified despite absence of corticalization. Diameter of MC was between 2.1 and 4 mm for nearly three quarters of the sample. In 80% of the sample trabeculation at the SGF was either decreased or not visible, and such cases showed correlation with absence of MC corticalization. Bifid MC affected 19% of the patients, mostly associated with additional mental foramina. Clinically significant anterior loop (>2 mm of anterior extension) was observed in 22-28%, depending on the method. Our findings, together with previously reported limitations of conventional exams, draw attention to the unpredictability related to anatomical variations in neurovascularization, showing the contribution of individual assessment through different views of three-dimensional imaging prior to surgical procedures in the mandible.

The aim of this study is to evaluate the anesthetic efficacy of mylohyoid and buccal nerve anesthesia at the posterior edentulous mandible versus regional anesthetic block to the inferior alveolar nerve in dental implant surgery. The study was composed of 2 groups. In the first group (group A), 14 voluntary adults (7 female and 7 male) received local infiltrations of 1 mL articaine HCl 4% with epinephrine 1/200,000 to the ipsilateral mylohyoid and buccal nerves. In the second group (group B, control; 9 female and 5 male adults), the inferior alveolar and the buccal nerve blocks were performed. Visual analog scales were obtained from patients to determine the level of pain during incision, drilling, implant placement, and suturing stages of implant surgery. A combination of buccal and mylohyoid nerve block offered an acceptable level of anesthesia. Two patients from group A stopped the ongoing surgery and had extraregional anesthesia by inferior alveolar nerve block. In group B, patients were operated on successfully. Local anesthetic infiltrations of the mylohyoid and the buccal nerve may be considered alternative methods of providing a convenient anesthetic state of the posterior mandibular ridge.

Background: Damage to the inferior alveolar nerve (IAN) during the extraction of impacted mandibular third molars in close proximity to the mandibular canal is a postoperative complication that most frequently occurs in patients 40 years and older., Methods: The authors evaluated the postoperative complications of 43 coronectomies of impacted mandibular third molars in 37 patients (17 men and 20 women, mean age [standard deviation] 31 [2] years). The authors used cone-beam computed tomographic images to determine that all of the teeth that underwent a coronectomy were in close proximity to the IAN., Results: The authors did not observe neurological injuries to the IAN or to the lingual nerve. One patient complained of intermittent pain and, 10 months after undergoing the coronectomy, underwent a second operation for extraction of the root fragments. The root extraction did not result in any neurological deficits, because the root fragments had migrated from the mandibular canal. One case of alveolitis was reported that manifested 15 days after the coronectomy., Conclusions: Coronectomies are safer to perform than complete extractions in situations in which the third molar is in close proximity to the mandibular canal. Root migration generally is asymptomatic, but in a case in which the patient underwent a second operation, the risk of the patient's experiencing neurological injuries was reduced., Clinical Implications: Coronectomy appears to be a valid surgical alternative in patients 40 years and older who are at a higher risk of experiencing neurological deficits than are younger patients.

Objectives: To compare two approaches to performing the inferior alveolar nerve block in the horse and to evaluate the consistency of described topographical landmarks., Design: Experimental cadaver model., Methods: Eleven cadaver heads were positioned to mimic a standing sedated horse and the position of the mandibular foramen approximated. The vertical approach to the approximate location of the mandibular foramen was undertaken and red dye was deposited. The angled approach was then undertaken and blue ink was used to identify it. The heads were then dissected to determine the location of the dye. Placement was categorised as a hit or a miss for each technique for each side of the head. The distance of the dye from the nerve was recorded. Straight lateral radiographs of the sectioned heads were taken to evaluate the topographical landmarks for performing this nerve block., Results: Each method was performed 22 times. A hit was achieved 16 times (73%) for the angled approach and 13 times (59%) for the vertical approach. There was no significant difference between the two approaches (P = 0.34). Radiographs revealed that the topographical landmarks used to approximate the mandibular foramen were relatively accurate., Conclusion: Both methods were found to be equivalently accurate. The previously reported topographic landmarks for locating the approximate position of the mandibular foramen on the medial aspect of the mandible were found to be accurate, but currently recommended doses of local anaesthetic may be excessive., (© 2012 The Authors. Australian Veterinary Journal © 2012 Australian Veterinary Association.)

Mandibular and maxillary nerve supplies are described in most anatomy textbooks. Nevertheless, several anatomical variations can be found and some of them are clinically relevant. Several studies have described the anatomical variations of the branching pattern of the trigeminal nerve in great detail. The aim of this review is to collect data from the literature and gives a detailed description of the innervation of the mandible and maxilla. We carried out a search of studies published in PubMed up to 2011, including clinical, anatomical and radiological studies. This paper gives an overview of the main anatomical variations of the maxillary and mandibular nerve supplies, describing the anatomical variations that should be considered by the clinicians to understand pathological situations better and to avoid complications associated with anaesthesia and surgical procedures., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objectives: Our objective was to develop an experimental model for the noninvasive and objective evaluation of facial nerve regeneration in rats using a motor nerve conduction test (electromyography)., Methods: Twenty-two rats were submitted to neurophysiological evaluation using motor nerve conduction of the mandibular branch of the facial nerve to obtain the compound muscle action potentials (CMAPs). To record the CMAPs, we used two needle electrodes that were inserted into the lower lip muscle of the rat. A supramaximal electrical stimulus was applied, and the values of CMAP latency, amplitude, length, area, and stimulus intensity obtained from each side were compared by use of the Wilcoxon test., Results: There was no significant difference (all p > 0.05) in latency, amplitude, duration, area, or intensity of stimuli between the two sides. The amplitudes ranged between 1.61 and 8.30 mV, the latencies between 1.03 and 1.97 ms, and the stimulus intensities between 1.50 and 2.90 mA., Conclusions: This is a noninvasive, easy, and highly reproducible method that contributes to an improvement of the techniques previously described and may contribute to future studies of the degeneration and regeneration of the facial nerve.

Purpose: To assess the clinical features of the inferior alveolar canal (IAC) using computed tomography (CT) and to analyze the significance of CT examination at third molar surgery., Materials and Methods: A retrospective cohort study was performed involving 99 patients (145 teeth). The relationship between cortication status, buccolingual position, and shape of the IAC on the CT image and inferior alveolar nerve (IAN) injury after third molar surgery were statistically analyzed., Results: The shape of the IAC was categorized into 3 groups: round/oval, teardrop, and dumbbell. IAN injury was observed in 7 of 145 cases (4.8%). All 7 cases exhibited absence of cortication; 3 were dumbbell shape and 4 were round/oval. According to logistic regression analysis of cases with absence of cortication, IAC shape was closely related to IAN injury., Conclusions: These results suggest that assessment of the IAC shape and cortication status at third molar surgery may be clinically useful., (Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: The aim of the present study was to evaluate the potential morphologic risk factors for postoperative neurosensory disturbance (NSD) after bilateral sagittal split osteotomy., Patients and Methods: The study subjects were 30 skeletal Class III patients (9 males and 21 females), with a mean age of 22.0 years (range, 16-39 years). All patients underwent bilateral sagittal split osteotomy for setback to correct mandibular prognathism. The bone marrow space between the outer mandibular canal and the lateral cortex of the ramus was measured on transaxial computed tomography images, and the length at the mandibular angle between the retromolar and gonion was measured on the lateral cephalograms. The NSD was tested bilaterally using discrimination to touch with the sharp head of a mechanical probe. Each patient was evaluated at 1, 3, and 6 months postoperatively., Results: The median bone marrow space was 1.96 mm (range, 0-4.5 mm), and median length of the mandibular angle was 30.93 mm (range, 23-37 mm). Neurosensory disturbance was present on 15 sides (25.0%) at 1 month postoperatively, 9 sides (15.0%) at 3 months postoperatively, and 7 sides (11.7%) at 6 months postoperatively. The difference in the incidence of NSD with a small bone marrow space and a long mandibular angle from that with a large bone marrow space and short mandibular angle was highly statistically significant (P = .006 and P < .01, respectively)., Conclusions: The frequency of NSD after bilateral sagittal split osteotomy in Class III cases was dependent not only on the position of mandibular canal, but also on the length of the mandibular angle. A lateral course of the mandibular canal and a long mandibular angle appeared to result in a high risk of injury to the inferior alveolar nerve, resulting in NSD owing to a compromised splitting procedure., (Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: To verify the utility of computed tomography (CT) in preventing inferior alveolar nerve (IAN) injury owing to lower third molar extraction in close relation to the IAN on orthopantomogram., Materials and Methods: A retrospective cohort study design of 150 lower third molar extractions was performed. Patients were divided in 2 groups: the CT group (n = 95) underwent panoramic radiography and mandibular CT and the control group (n = 55) underwent only panoramic radiography., Results: Six extractions (4%) in the control group and 15 (10%) in the CT group resulted in IAN impairment (P > .05). Logistic regression models did not show that undergoing CT decreased the risk of IAN injury from lower third molar extraction., Conclusions: Patient age and positive radiographic signs (darkening of the root and narrowing of the inferior alveolar canal) were associated with more requests for CT scanning. CT does not seem to significantly decrease the risk of producing IAN injury., (Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: Normally developing children learn to produce intelligible speech during rapid, non-uniform growth of their articulators and other vocal tract structures. The purpose of this review is to focus attention on the consequences of peripheral growth and development for the acquisition of lingual control for speech production. This paper (1) reviews physiological underpinnings of tongue shaping and movements that are likely to be changing in young children; (2) estimates, from previously published studies, the net consequences of growth of multiple vocal tract structures on lingual control; (3) integrates our findings with the example of [R] production, and (4) highlights areas where further investigations would be most helpful., Patients and Methods: The authors searched the literature, including the PubMed database, for studies of the development of muscle proteins, muscle fibers, and motor units of the tongue, and of the growth of the tongue, jaw, adenoids, soft and hard palates, oral and pharyngeal cavities, and the vocal tract as a whole., Conclusions: Substantial anatomical and muscular data sets focused on children from 1-4 years of age, and rigorous definitions of the tongue boundaries are needed., (Copyright © 2012 S. Karger AG, Basel.)

Fracture of mandibular body at the level of P3-P4 with symphysis rupture was modeled, reposition and transosseous osteosynthesis with a specially developed device were performed under anesthesia in the operating room in 17 adult mongrel dogs in order to specify the pathogenesis and the dynamics of injury and jaw nerve regeneration. It has been established, that the arrangement of the neurovascular bundle in medullary canal predetermines the development of acute and chronic compression-and-ischemic neuropathy even if accurate reposition of bone fragments takes place. The histological signs of nerve fiber regeneration, the loss of the quantity of myelin-free nerve conductors and the retrograde spreading of degenerative changes in myelinized nerve conductors, including regenerating ones, have been found beginning from 4 weeks after injury. It has been concluded, that spontaneous nerve regeneration in case of mandibular fractures should be actively supported by neuroprotective, anti-edematous and anti-inflammatory therapy.

Objective: Anatomical variations of the dental canal structures are present in a small proportion of the population and often go undiagnosed. In such cases, there could be an increased risk of complications during surgery and failure of anesthesia. The aim of this study was to search for anatomical anomalies in a relatively large random population by using 3-T high-field magnetic resonance imaging (MRI)., Methods: Sixty-four dentate patients were examined using a modified T2 space sequence. The scans were analyzed with respect to anatomical features, variations, and rarities of the mandibular canal, mental canal, incisive canal, and the nutrient canals., Results: Sixteen anatomical variations were identified in the study, and some of those images are presented., Conclusion: High-resolution MRI performed on a 3.0-T system can effectively visualize variations of the inferior alveolar nerve in dentate mandible of patients. Thus, MRI can be used in dentistry and oral surgery in vague or unclear cases, which could not be clarified by orthopantomography or even a computed tomographic scan, to improve patient care.

Face transplantation is a novel treatment for the reconstruction of massive facial defects. To date 13 cases have been performed. The technical aspects of a composite lower face transplantation including the tongue, floor of the mouth, and most of the mandible are detailed. The transplantation was performed in August 2009 in an HIV-positive, postoncologic patient. A preparatory surgery for nerve identification was performed. Facial composite tissue was procured after cardiac cessation. Revascularization was performed to the right subclavian artery with an internal shunt between the internal carotid arteries. At 16 months posttransplantation the patient is swallowing, without evidence of malignancy recurrence or HIV replication., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Neurosensory disturbance after sagittal split osteotomy is a common complication. This study evaluated the course of the mandibular canal at three positions using computed tomography (CT), assessed the risk of injury to the inferior alveolar nerve in classical sagittal split osteotomy, based on the proximity of the mandibular canal to the external cortical bone, and proposed alternative surgical techniques using computer-assisted surgery. CT data from 102 mandibular rami were evaluated. At each position, the distance between the mandibular canal and the inner surface of the cortical bone was measured; if less than 1mm or if the canal contacted the external cortical bone it was registered as a possible neurosensory compromising proximity. The course of each mandibular canal was allocated to a neurosensory risk or a non-neurosensory risk group. The mandibular canal was in contact with, or within 1mm of, the lingual cortex in most positions along its course. Neurosensory compromising proximity of the mandibular canal was observed in about 60% of sagittal split ramus osteotomy sites examined. For this group, modified classic osteotomy or complete individualized osteotomy is proposed, depending on the position at which the mandibular canal was at risk; they may be accomplished with computer-assisted navigation., (Copyright © 2011 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

The morphology of the inferior alveolar nerve is a very important factor for all surgical procedures in the mandibular region. The aim of this anatomical and histological study was to describe the intramandibular course and the microscopic histology of the inferior alveolar nerve in the dissected human cadaver. Twenty partially dentulous hemimandible specimens from human cadavers were dissected and embalmed, and the findings were interpreted by standard and histological imaging. The result of this study showed that the inferior alveolar nerve comprises two larger nerves that are separately wrapped in perineural sheaths and spirally twisted around each other. The mental nerve exits through the mental foramen in the premolar region and the dental nerve continues from the premolar region as the incisive nerve in the incisive canal. These findings provide relevant data for clinical dentistry, especially when planning oral and dental operative treatment procedures in the mandibular region.

Introduction: The retromolar canal is an anatomic structure of the mandible with clinical importance. This canal branches off from the mandibular canal behind the third molar and travels to the retromolar foramen in the retromolar fossa. The retromolar canal might conduct accessory innervation to the mandibular molars or contain an aberrant buccal nerve., Methods: Patients referred for panoramic radiography were consecutively enrolled, provided a limited cone-beam computed tomography (CBCT) scan had also been taken in the area of interest. Radiographs were retrospectively screened for the presence of a retromolar canal, and linear measurements (distance to second molar, height, width) were taken., Results: One hundred twenty-one sides in 100 patients were evaluated (100 unilateral and 21 bilateral cases). A total of 31 retromolar canals were identified with CBCT (25.6%). Only 7 of these canals were also seen on the corresponding panoramic radiographs. The existence of a retromolar canal was not statistically related to gender or side. With regard to the linear measurements, the mean distance from the retromolar canal to the second molar was 15.16 mm (±2.39 mm), the mean height of the canal was 11.34 mm (±2.36 mm), and the mean width was 0.99 mm (±0.31 mm)., Conclusions: This radiographic study documents a frequency of 25% for the presence of a retromolar canal. The clinician is advised to preserve this anatomic variation when performing surgery in the retromolar area and to consider additional locoregional anesthesia in the case of failed mandibular block anesthesia., (Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

The inferior alveolar nerve (IAN) is vulnerable to injury from mandible fractures and surgical procedures so anatomical variations of IAN are important. Postoperative sensory alteration of the lip and chin region is high after mandibular orthognathic surgery. The incidence of IAN paresthesia following sagittal split ramus osteotomy (SSRO) ranges from 54% to 86% at 4-8 days, 41 to 75% at 1 month, 33 to 66% at 3 months, 17 to 58% at 6 months and 15 to 33% at 1 year postoperatively. This study determined the anatomical position of the mandibular canal in relation to cortical bone and molar teeth in Chinese using archived CT records. The mandibular canal was the farthest from the buccal cortex at the second molar region (mean 6.79mm; minimum distance 4.80mm). The anatomical location of the mandibular canal in local Chinese compares with studies on Asian cadavers. The mandible body was thickest in the region of the second molar (11.9mm). The vertical buccal cut for SSRO should be in the region of the mandibular second molar where the bone is thickest and the mandibular canal is furthest from the buccal cortex. The safe depth for the vertical buccal cut is 4.8mm (minimum horizontal distance)., (Copyright © 2011 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

There are difficulties for dental implant use in posterior mandible when there is little bone height for implant placement. Among the treatment alternatives available, there is no direct comparison between short implants and conventional implants placed with lateralization of the inferior alveolar nerve. The present study aimed to comparatively evaluate the risk of peri-implant bone loss of the above treatments. With this aim, computed tomography scans of mandibles were processed, and implants and prosthetic components were reverse engineered for reconstruction of three-dimensional models to simulate the biomechanical behavior of 3-element fixed partial dentures supported by 2 osseointegrated implants, using simulations with the finite element method. The models of implants were based on MK III implants (Nobel Biocare) of 5- and 4-mm diameter by 7-mm length, representing short implants, and 4- and 3.75-mm diameter by 15-mm length, representing implants used in lateralization of the inferior alveolar nerve. All models were simulated with prestress concerning the stresses generated by the torque of the screw. Axial and oblique occlusal loads at 45% were simulated, resulting in 8 different simulations. The results showed that the risk for bone loss in osseointegrated implants is greater for treatments with short implants.

Our aim was to find out whether the quality of bone around the inferior alveolar nerve is correlated with neurosensory disturbance to the nerve after sagittal split ramus osteotomy (SSRO) in patients with mandibular prognathism. Computed tomograms (CT) were taken of 35 patients with mandibular prognathism and 35 without. To assess the density of bone around the inferior alveolar nerve, the width of the buccal cortical bone in the mandibular second molar regions was measured on CT. The Hounsfield units (HU) in the same regions were also measured. The number of HU in the mandible around the second molar regions was significantly higher (p<0.01) in those with neurosensory disturbance (p<0.01). The quality of bone measured by HU is associated with an increased risk of neurosensory disturbance, but the width of buccal bone is not., (Copyright © 2010 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Background: The author describes the use of the infiltration anesthetic technique to anesthetize mandibular teeth in adults and explores its mechanism of action., Methods: The author reviewed articles describing randomized controlled trials of the mandibular infiltration anesthetic technique in healthy participants., Results: The author found that using the mandibular infiltration anesthetic technique can produce anesthesia in adult mandibular teeth. The success was dose dependent and the choice of anesthetic solution was significant; 4 percent articaine with 1:100,000 epinephrine was more effective than 2 percent lidocaine with 1:100,000 epinephrine. Combining buccal and lingual infiltrations increased success in the mandibular incisor region. The success of the mechanism of infiltration of anesthetic at the mandibular first molar appeared to depend on the mental foramen., Conclusions: The mandibular infiltration anesthetic technique is an effective method of anesthetizing mandibular incisors. Four percent articaine with epinephrine appears to be the preferred solution., Clinical Implications: The choice of anesthetic solution is important when using the infiltration anesthetic technique in the adult mandible.

Background: and Overview. The limited success rate of the standard inferior alveolar nerve block (IANB) has led to the development of alternative approaches for providing mandibular anesthesia. Two techniques, the Gow-Gates mandibular nerve block and the Akinosi-Vazirani closed-mouth mandibular nerve block, are reliable alternatives to the traditional IANB. The Gow-Gates technique requires the patient's mouth to be open wide, and the dentist aims to administer local anesthetic just anterior to the neck of the condyle in proximity to the mandibular branch of the trigeminal nerve after its exit from the foramen ovale. The Akinosi-Vazirani technique requires the patient's mouth to be closed, and the dentist aims to fill the pterygomandibular space with local anesthetic., Conclusion: Both techniques are indicated for any type of dentistry performed in the mandibular arch, but they are particularly advantageous when the patient has a history of standard IANB failure owing to anatomical variability or accessory innervation., Clinical Implications: Having the skill to perform these alternative anesthetic techniques increases dentists' ability to provide successful local anesthesia consistently for all procedures in mandibular teeth.

Regional nerve blocks are commonly used to provide analgesia for dental and oral surgical procedures. The purpose of this study was to demarcate the areas of the mandible that would be desensitized by application of the mental nerve block. Seven healthy mixed-breed dogs were anesthetized for an annual dental examination and professional teeth cleaning procedure. Bupivacaine HCl (0.4 ml/ m2) was administered at one middle mental foramen based on previously described techniques for the mental nerve block. A noxious stimulus was applied at 23 predetermined ipsilateral mandibular locations using pressure from a mosquito hemostat on the mucocutaneous junction (MCJ) and a dental curette on the vestibular mucogingival line (MGL) at the incisor canine, and premolar teeth; and, the mesial and distal aspects of the first molar tooth. A thermal stimulus using a refrigerant spray on a cotton ball was applied to the ipsilateral canine, third premolar and fourth premolar teeth; and, the mesial and distal aspects of the first molar tooth. Demonstration of nociception or anesthesia was noted and the responses tabulated. The area of desensitized tissues was smaller than expected and highly variable within the study group. In conclusion, the unilateral mental nerve block does not reliably provide generalized desensitization to tissues of the incisive and rostral regions of the mandible. Although the mental nerve block is recommended, other modes of analgesia should be emphasized for surgical and dental procedures involving these areas.

Background: and Overview. The provision of mandibular anesthesia traditionally has relied on nerve block anesthetic techniques such as the Halsted, the Gow-Gates and the Akinosi-Vazirani methods. The authors present two alternative techniques to provide local anesthesia in mandibular teeth: the periodontal ligament (PDL) injection and the intraosseous (IO) injection. The authors also present indications for and complications associated with these techniques., Conclusions: The PDL injection and the IO injection are effective anesthetic techniques for managing nerve block failures and for providing localized anesthesia in the mandible., Clinical Implications: Dentists may find these techniques to be useful alternatives to nerve block anesthesia.

The effect of age on the anteroposterior (A-P) position of the mandibular foramen (MF) and on the size of the gonial angle (GA) was evaluated in this study. From an Israeli Bedouin population, 121 dry mandibles with primary (36), mixed (26), and permanent dentitions (59) were analyzed. The A-P position of the MF perpendicular to the posterior border of the ramus was measured with a digital caliper. A mandibulometer was used to evaluate the GA. The MF distance from the posterior border of the ramus increased significantly with age by 66% from primary (7.75 mm) to permanent (12.9 mm; P < 0.001). Similarly, the MF distance from the posterior border of the ramus relative to the total ramus width in A-P dimension increased significantly (21.4%) with altered dentitions from primary (0.28) to late permanent dentition (0.34; P < 0.001). The GA decreased significantly with age from 140.17° ± 5.9° (primary dentition) to 123.61° ± 6.9° (late permanent dentition; P < 0.001). The anterior movement of the MF and the decreased size of the GA that occurred with changing dentition were related to growth process. The MF moves anteriorly, and the GA decreases with age., (Copyright © 2011 Wiley-Liss, Inc.)

Objective: To evaluate the diagnostic accuracy of the cone beam computed tomography (CBCT) in judging the relationship between the impacted mandibular third molar (IMTM) and the inferior alveolar canal (IAC)., Methods: Sixty IMTM superimposing on the canal partially or touching the canal in line on panoramic radiograms were examined by CBCT. All CBCT images of these cases were observed by two dentists respectively. Then, all these IMTM were extracted by minimally invasive surgery, and the conditions of the IMTM sockets were observed. Two dentists observed the CBCT images independently and reached a consensus. Diagnosis test was performed in this study., Results: Eight IMTM sockets were bleeding during the extracted operation, and whether the IAC wall was broken could not be judged. The other 52 IMTM sockets were clear and the walls of IAC were broken in 29 IMTM extractions. The sensitivity, specificity, Youden index, positive predictive value and negative predictive value of CBCT were 82.8%, 87.0%, 88.9% and 80.0% respectively. The diagnostic accuracy judged by the two dentists and Kappa coefficient were calculated as 84.6% and 0.800., Conclusions: The CBCT examination had good authenticity and reliability, and it was very helpful in predicting the actual relationship between the IMTM and IAC.

Objectives: To study the radiographic location of the mental foramen and appearance of the inferior alveolar canal and the relationship between image gray values and the clarity of inferior alveolar canal on the digital panoramic images and to evaluate if the histogram equalization of the digital image would improve the visualization of the inferior alveolar canal outline on the digital panoramic images in the mandible., Methods: Five hundred digital panoramic images were evaluated by two examiners using a specific inclusion criteria. Only the right side of the mandible was studied. Chi-square analyses were used for comparisons of distributions. Mean and median pixel values were analyzed separately with a one-way analysis of variance. Also, percentages were calculated to report the usefulness of the histogram equalization for visualization of canal., Results: RESULTS show variation in location of mental foramen. Most frequent location of the mental foramen was reported as first and second premolar region. Chi-square analysis showed that the frequency of occurrence of the mental foramen was equally probable for any of the three locations. The study did not find significant usefulness of the gray values obtained from the histogram equalization in predicting the clarity of inferior alveolar canal outlines., Clinical Significance: Knowing the normal relationship and the anatomical variation of the maxillofacial structures for each patient is important for surgical implant treatment planning to avoid future complications. It is also important to be familiar with the advantages and limitations of diagnostic aids available before making treatment planning decisions based on such findings., Keywords: Digital imaging, Panoramic, Inferior alveolar canal, Mental foramen. How to cite this article: Pria CM, Masood F, Beckerley JM, Carson RE. Study of the Inferior Alveolar Canal and Mental Foramen on Digital Panoramic Images. J Contemp Dent Pract 2011;12(4):265-271. Source of support: Nil Conflict of interest: None declared.

Background: Mental foramen (MF) is an anatomical structure of particular importance in local anesthesia and surgical procedures in terms of achieving effective mandibular nerve blocks and avoiding injuries to the neurovascular bundles., Aim: To determine the morphometry and morphology of MF in south Andhra population of India, hitherto unreported., Materials and Methods: Ninety dry dentulous mandibles of both sexes were examined for position, size, shape and number of MF., Results: Various parameters investigated are, the horizontal distance between (1) symphysis menti and MF was 27.2 mm on right and 27.7 mm on the left, (2) MF and posterior border of ramus was 70.7 mm on both sides, vertical distance between (3) MF and inferior border of mandible was 16.5 mm on right and 14.3 mm on left, (4) alveolar crest and MF was 13.7 mm on right and 16.4 on left, (5) distance between the MF and below the apex of premolar socket was +2.8 mm on right and +3.5 mm on left and above the socket was -2.8 mm on right and -2.7 mm on left. Occurrence of MF below the second premolar tooth was found to be highest (73.2%). Average size of MF was larger on left and its way of exit was in postero-superior direction. Shape of MF was round in 79% and oval in 21% and double MF was found in 8.9% of mandibles., Conclusions: In the present study, most common position of MF was found below the apex of second premolar in 73.2% and between the second premolar and first molar in 19% of mandibles. The other morphometrical findings of this study may be implicated by dental practitioners and maxillofacial surgeons.

Purpose: To identify the specific radiographic signs on orthopantomograms that are positive predictors of intraoperative inferior dental nerve (IDN) exposure and postoperative IDN deficit in lower third molar surgery., Materials and Methods: A prospective clinical cohort of patients with lower third molars with specific radiographic signs showing a close proximity of the roots to the IDN who underwent total excision at our center from June 2006 to June 2008 were recruited as the study group. The prevalence of intraoperative IDN exposure and postoperative IDN deficit were recorded. The correlations between the various radiographic signs and the prevalence of IDN exposure and deficit were analyzed. The prevalence of IDN deficit in the sample was compared with an age-, gender-, and operator experience-matched control group of patients who had undergone lower third molar surgery without any of the radiographic signs present., Results: Patients with a total of 178 lower third molars with 1 or more of the specific radiographic signs present were recruited as the study group. The prevalence of IDN deficit in the study group (5.1%) was significantly greater than that in the control group (0.56%; P = .01). In the study group, darkening of root and displacement of the inferior dental canal by the root were radiographic signs significantly related to IDN exposure (P = .001 and P = .019, respectively). Darkening of the root was the only sign significantly related to a postoperative IDN deficit (P = .016). When 2 or more radiographic signs were present, the risk of a postoperative IDN deficit was significantly increased (P = .001)., Conclusions: Darkening of the root and displacement of the inferior dental canal by the root were positive predictors of intraoperative IDN exposure. Darkening of the root or the presence of 2 or more radiographic signs were positive predictors of a postoperative IDN deficit., (Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: The aim of the present study was to investigate whether a difference exists in the location of the displaced inferior alveolar canal (IAC) and neurovascular bundle (toward the buccal or lingual cortex) among odontogenic tumors and vascular lesions. If some consistency exists in the manner in which the canal and bundle are displaced on radiographic examination, the nature of the mandibular lesion under examination could be anticipated. This information would assist the surgical team in treatment planning, diagnostic biopsy, and resection, especially in cases of intraosseous vascular pathologic findings., Materials and Methods: A retrospective review of the computed tomography images obtained for odontogenic tumors and vascular anomalies treated at the Department of Oral and Maxillofacial Surgery, University of Illinois at Chicago, from January 2000 to June 2010 was undertaken. The IAC and neurovascular bundle were traced from the lingula to the mental foramina, and its location within the mandible was recorded at 3 specific points., Results: In the odontogenic tumor group, we found that the canal with the neurovascular bundle was displaced either toward the buccal cortex of the mandible or the inferior border, but it was never identified lingually. In contrast, all the vascular anomalies had displaced the structures toward the lingual aspect of the mandible at all selected points., Conclusions: To our knowledge, this is the first study to have examined the potential differences in the displacement of the inferior alveolar neurovascular bundle caused by the 2 commonly encountered pathologic entities in the maxillofacial skeleton: odontogenic tumors and vascular anomalies. We identified a striking difference in the manner of the IAC and its contents that was consistent among the tumors in the 2 groups. The location of the IAC in relationship to the pathologic entity under investigation could prove valuable in the differential diagnosis and assist with planning the biopsy. Additional investigation with a larger number of cases of these 2 groups of lesions involving the mandible is warranted to confirm our preliminary findings., (Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

In a patient with hypoaesthesia of the central region of the mandible, no oral cause could be found which could explain his complaint. Further examination by a neurologist and a specialist in internal medicine revealed the numb chin syndrome. The syndrome was caused by meningeal localisation of a high-grade B-cell lymphoma stade IV. After intensive chemotherapy and radiotherapy of the skull, the complaints disappeared.

Anomalous patterns in the human body are usually seen in cadaver dissections and during investigations. We have studied 50 cadavers of southern Indian men and women to find the variable origins of the mylohyoid nerve in the infratemporal region. We discovered an unusual origin of the nerve during a routine educational dissection. Here we describe the course of the aberrant nerve and its distributing branches. Awareness of such anatomical variations could help during surgical or dental interventions., (Copyright © 2010 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Purpose: Close proximity of the inferior alveolar nerve (IAN) to mandibular third molars (MTMs) may result in nerve injury during the extraction of third molars. Alternative surgical techniques, such as coronectomy, have been suggested to decrease this risk. This study examined a new alternative technique, the pericoronal ostectomy (PO), that is intended to decrease IAN injury in high-risk cases., Patients and Methods: This prospective clinical cohort study consisted of 14 patients with 17 MTMs in close relation to the IAN. All patients were subjected to 2- and 3-dimensional preoperative radiographic evaluations. Selected patients with mesioangular and vertical bone impactions were treated by the staged PO technique. An institutional review board approval from the University of the Pacific was given to this study., Results: Because of the PO procedure, all 17 high-risk MTMs in the study erupted to a more occlusal position away from the danger zone of the IAN and were eventually removed (mean distance of eruption, 2.0 mm). Three patients reported a transient neurosensory deficit, 2 with the IAN and 1 with a lingual nerve. All 3 had a full resolution of symptoms within 3 months of the postoperative period., Conclusion: The PO technique appears to be an additional viable alternative technique to extraction of MTMs in intimate proximity to the IAN., (Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: A retrospective study was done to evaluate the use of transalveolar implant placement in the mandible posterior to the mental nerve., Materials and Methods: Ten patient charts were reviewed of twenty implants placed transalveolarly with evaluation of function, osseointegration, and bone level for 1 year by unregistered periapical x-rays., Results: Ten patients which received twenty transalveolar implants were followed for 1 year. One implant failed. There were no significant complications encountered from the procedure., Conclusion: All On Four treatment of mandibles with relatively anterior mental nerve locations may be successfully treated with transalveolar implant placement posterior to the foramen., (Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

A thorough knowledge of the anatomy of the pterygomandibular space is essential for the successful administration of the inferior alveolar nerve block. In addition to the inferior alveolar and lingual nerves, other structures in this space are of particular significance for local anaesthesia, including the inferior alveolar vessels, the sphenomandibular ligament and the interpterygoid fascia. These structures can all potentially have an impact on the effectiveness of local anaesthesia in this area. Greater understanding of the nature and extent of variation in intraoral landmarks and underlying structures should lead to improved success rates, and provide safer and more effective anaesthesia. The direct technique for the inferior alveolar nerve block is used frequently by most clinicians in Australia and this review evaluates its anatomical rationale and provides possible explanations for anaesthetic failures., (© 2011 Australian Dental Association.)

This study investigated the extent of complete anaesthesia from buccal nerve block. 40 healthy Thai patients (20 males; 20 females) requiring buccal nerve block for surgery were studied. After the buccal nerve was blocked, the buccal mucosa was explored using a sharp probe to map out the extent of anaesthesia. The operation was carried out after inferior alveolar and lingual nerve block. The extent of the anaesthesia was mainly from the retromolar area to the second molar, followed by the first molar to the second premolar, whilst the first premolar to the central incisor was the area least affected. An important finding of this study was that the anaesthetized extent of some patients extended to the anterior region on the same quadrant. This study showed the affected areas of buccal nerve anaesthesia extended through the buccal mucosa from the first premolar to the central incisor in some patients. It can serve as another informative indication for lower anterior surgery., (Copyright © 2011 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Introduction: It is mandatory to know the anatomic path of the mandibular nerve and its intra-mandibular connections for numerous odontology, stomatology, and maxillofacial surgical procedures. We present a computed tomography study of the mandibular nerve intra-mandibular path., Patients and Method: The computed tomography of 14 mandibles was performed (vestibulo-lingual cross-section) and four landmarks were defined behind the mental foramen. At each landmark, we measured the distance between the alveolar canal and the two cortical layers in the vestibulo-lingual plane, and the distance between the alveolar canal and the alveolar crest, and the inferior border of the mandible in the vertical plane., Results: In the vestibulo-lingual plane, the mandibular nerve is located close to the vestibular cortical layer, then to the lingual cortical before it exits. In the crestal plane, it is located at the superior third of the inferior border of the mandible., Discussion: In spite of anatomical variability, there is a globally common path which means that the utmost caution should be taken by performing systematic imaging before undertaking any surgery close to the nerve., (Copyright © 2011. Published by Elsevier Masson SAS.)

We describe a case of proximal mandibular nerve block with ropivacaine, using electrolocation, for perioperative pain management in a geriatric dog undergoing rostral mandibulectomy. The patient did not require intraoperative analgesia or analgesic supplementation for 8 h after the end of the surgery.