Effect of Inferior Alveolar Nerve Transection on the Inorganic Component of Molars of Rat Mandible.

The objective of the study was to determine the effects of inferior alveolar nerve transection on inorganic components in mandibular molars of the rat. We used 26 male laboratory rats of the Wistar strain for the study, age 7-9 weeks. The rats were divided in three groups. The control group (intact) included 6 rats. The surgery was performed under general anesthesia. The experimental group included (group with the nerve transected on the left) included 12 rats. The sham group (group with the nerve prepared without transection) included 8 rats. The animals were sacrificed after 4 weeks. Molars from the left and right sides of the mandible were extracted. Element content levels were determined using inductively coupled plasma mass spectrometry. The following elements were determined in all samples: magnesium (Mg), sodium (Na), potassium (K), calcium (Ca), zinc (Zn), and strontium (Sr). The nerve transection caused: a reduction of the contents of Ca and Sr in the mandibular molars; an increase in the contents of Mg and Zn; a difference arrangement of both sides for Na. The surgery approach itself caused a decrease in the contents of Na and K in the experimental and sham groups; the difference in K in M3 between the left and right sides disappeared due to the surgery. Our results have confirmed the hypothesis of inferior alveolar nerve transection having an effect on inorganic components in mandibular molars in the rat.

The effect of delayed photobiomodulation on neurosensory disturbance recovery after zygomatic trauma: A parallel controlled clinical trial.

INTRODUCTION: Zygomatic fractures are usually accompanied with neural complications, which are routinely treated by surgery or medication. However, photobiomodulation has been proven as a non-invasive method with better results in nerve's regeneration and repair. Therefore, in this study, we aimed to investigate the healing effect of photobiomodulation on neurosensory defect after facial trauma. PATIENTS AND METHODS: In this parallel controlled clinical trial, 35 control cases and 36 patients with zygomaticomaxillary complex (ZMC) fractures as well as the sustained infraorbital nerve paresthesia were included. Afterward, Laser irradiation was applied using a GaAlAs diode laser (810 nm, 27 J/cm2, 200 mW) on 12 points on malar area of paresthesia during 12 sessions within six weeks. Neurosensory evaluations were performed in four sessions as follows: at baseline, the end of treatment, one month, and three months after the last session of irradiation, which were achieved through three tests including visual analogue scales (VAS) for general sensitivity, two-point discrimination, and pain discrimination. Repeated measure ANOVA, independent t-test, and Chi-square test were used for comparing time trends, each time point, and gender, respectively. P-values less than 0.05 were considered to be statistically significant. RESULTS: The patients and controls were matched in both terms of age and gender. Baseline results showed non-significant differences between the two groups based on the VAS, pain, and two-point discrimination. Moreover, for VAS scale, some significant differences were observed between the groups by passing "one month and three months from therapy". Pain and two-point discriminations showed a significant difference between the intervention and control groups in "one month after therapy" and "at the end of the therapy, one month after therapy, and three months after therapy", respectively. CONCLUSION: Photobiomodulation could be considered as an effective treatment option for post-traumatic neurosensory disturbance of facial area in terms of VAS, pain and two-point discrimination, even if not performed early after trauma.

Sensory denervation increases potential of bisphosphonates to induce osteonecrosis via disproportionate expression of calcitonin gene-related peptide and substance P.

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a serious side effect of systematic administration of bisphosphonates (BPs). Sensory innervation is crucial for bone healing. We established inferior alveolar nerve injury (IANI) and inferior alveolar nerve transection (IANT) models characterized by disorganized periosteum, increased osteoclasts, and unbalanced neuropeptide expression. Zoledronate injection disrupted neuropeptide expression in the IANI and IANT models by decreasing calcitonin gene-related peptide (CGRP) and increasing substance P (SP); associated with this, BRONJ prevalence was significantly higher in the IANT model, followed by the IANI model and the sham control. CGRP treatment significantly reduced BRONJ occurrence, whereas SP administration had the opposite effect. In vitro, RAW 264.7 cells were treated with BPs and then CGRP and/or SP to study changes in zoledronate toxicity; combined application of CGRP and SP decreased zoledronate toxicity, whereas CGRP or SP applied alone showed no effects. These results demonstrate that sensory denervation facilitates the occurrence of BRONJ and that CGRP used therapeutically may prevent BRONJ progression, provided that SP is also present. Further studies are necessary to determine the optimal ratio of CGRP to SP for promoting bone healing and to uncover the mechanism by which CGRP and SP cooperate.

Effect of inferior alveolar nerve transection on the inorganic component of bone of rat mandible.

OBJECTIVE: The aim of the study was to test the effect of transecting the inferior alveolar nerve on the inorganic bone component of the rat mandible. METHODS: 7-9 weeks old, male Wistar rats were used for the study. The animals were divided in 3 groups: control, experimental (nerve was transected) and sham (nerve was only prepared but not transected). After 4 weeks, the animals were killed, their teeth were extracted, and the mandibular bone was divided in 4 parts. Inductively coupled plasma mass spectrometry was used to the levels of 7 elements in the bone. RESULTS: The study results demonstrate that transection of the inferior alveolar nerve caused a decrease in calcium, iron, and strontium, and an increase of zinc. It caused the differences in potassium contents between the sides was significantly lower in the experimental group. The increase in the magnesium content, and decrease of sodium and potassium in the experimental group, as well as differences in the contents of: magnesium, sodium, potassium, iron and zinc between individual locations in the mandible are associated with the surgical approach. CONCLUSION: The results support our hypothesis - that sensory innervation has an impact on the inorganic component of the mandibular bone.

Effectiveness and safety of the use of gracilis muscle for dynamic smile restoration in facial paralysis: A systematic review and meta-analysis.

BACKGROUND: Smiling is a fundamental component of social interactions. Significant challenges arise for patients with facial palsy. One of the key procedures for dynamic smile restoration is the microneurovascular transfer of a gracilis muscle. We aimed to assess the effectiveness and safety of dynamic smile reanimation surgery using the free gracilis muscle unit in patients with facial palsy. METHODS: We conducted a systematic review and meta-analysis of studies reporting surgical outcomes of dynamic smile restoration using free gracilis muscles identified from EMBASE, Medline, and Web of Science databases from their inception to March 15, 2018. Two-stage screening and data extraction were performed by two independent reviewers. Pooled proportions were calculated using random-effects models. RESULTS: Thirty-one studies including 1647 patients who underwent 1739 free gracilis flaps were included. Twelve (38.7%) studies measured perioperative smile excursion change using six different tools. Six of these studies were homogeneous and were used in meta-analyses of smile excursion improvement, which revealed a mean change of 7.5 mm (95% CI 6.0-9.0 mm, I2 86.7%) perioperatively. Twenty (64.5%) studies reported perioperative complications, and pooled proportions of flap failures were of 2.9% (95% CI 1.3-4.5%, I2 47.7%). CONCLUSIONS: Dynamic smile restoration using a free gracilis muscle may represent an effective procedure to regain oral commissure motion and is associated with an approximately 3% rate of flap failure. Masseteric nerve coaptations lead to larger improvements in perioperative smile excursion (10 mm) than cross-facial nerve grafts (6.8 mm). Future studies with homogeneous reporting of smile excursion and patient-reported outcome measures are needed.

Ultrasound-Guided Inferior Alveolar Nerve Block in the Horse: Assessment of the Extraoral Approach in Cadavers.

Blinded techniques to desensitize the inferior alveolar nerve (IAN) include intraoral, angled, and vertical extraoral approaches with reported success rates of 100%, 73%, and 59%, respectively. It has not been determined whether an ultrasound-guided extraoral approach is feasible. Further, the fascicular nature of the inferior alveolar and lingual nerves of the horse has not been described. The objectives of this study were to describe a low-volume ultrasound-guided vertical extraoral inferior alveolar nerve block technique and to describe the fascicular nature of these nerves. An ultrasound-guided approach to the IAN was conducted with a microconvex transducer and an 18-G, 15-cm spinal needle using a solution containing iodinated-contrast and methylene blue dye. Accuracy was assessed by contrast visualized at the mandibular foramen on computed tomography (CT) and methylene blue dye staining of the nerves on gross dissection. Sections of inferior alveolar and lingual nerves were submitted for histological analysis. Assessment by CT and dissection determined success rates of 81.3% and 68.8%, respectively; 68.8% of injections had inadvertent methylene blue dye staining of the lingual nerve. Nerve histology revealed both the inferior alveolar and lingual nerves to be multifascicular in nature. Mean fascicle counts for the inferior alveolar and lingual nerves were 29 and 30.8, respectively. The technique is challenging and no more accurate than previously published blinded techniques. Any extraoral approach to the IAN is likely to also desensitize the lingual nerve.

Patient experience in nerve-to-masseter-driven smile reanimation.

INTRODUCTION: The nerve-to-masseter is one of the most frequently used neural sources in smile reanimation surgery. Very little information has been reported on patient experience with regard to reanimated smile usage and sequelae following transfer. The aim of this study was to quantify patient perception of nerve-to-masseter use in smile reanimation surgery. METHODS: An online questionnaire was developed based on the clinical expertise of our team, patient interviews, and existing questionnaires of facial palsy-related quality of life and temporomandibular joint dysfunction. All patients treated with nerve-to-masseter-driven smile reanimation surgery, both nerve transfers and muscle transplantations, between 2007 and 2016 with a valid email address were invited to participate. RESULTS: Of 171 operated patients, 122 with a valid email address were invited to participate. Seventy-one patients responded (63.4% female, mean age 51.1 years) after a median follow-up of 3.8 years. A voluntary smile while biting down at least "most of the time" was reported by 83.1% of patients; 46.5% reported ability to smile on the affected side without bite. A "normal" or "almost normal" spontaneous smile was reported in 23.9% of patients. A total of 18.3% of patients self-reported masseter muscle atrophy, and 1.4-14.1% reported temporomandibular joint dysfunction. Forty-one patients (57.7%) reported prandial movement of the face at least "most of the time," with 9 patients (12.7%) considering this bothersome. CONCLUSION: Patients report good voluntary smiling ability following nerve-to-masseter-driven smile reanimation surgery, with low rates of sequelae.

Does the Length of Dental Implants Inserted in Areas of Inferior Alveolar Nerve Lateralization Interfere on Mandibular Resistance to Fracture?

The aim of this study was to compare, in vitro, the mechanical resistance to vertical displacement of the mandible after osteotomy for lateralization of the inferior alveolar nerve and installation of dental implants. One hundred eighty polyurethane mandibles were equally divided into 6 groups: G1-intact hemi-mandibles (control group), G2-hemi-mandibles after osteotomy for lateralization of the inferior alveolar nerve, G3-hemi-mandibles with installation of 3 bicortical dental implants (3.75 × 13 mm), G4-hemi-mandibles with installation of 3 dental implants that did not reach the basal cortical bone (3.75 × 11 mm), G5-hemi-mandibles after osteotomy for lateralization of the inferior alveolar nerve and installation of 3 bicortical dental implants (3.75 × 13 mm) and G6-hemi-mandibles after osteotomy for lateralization of the inferior alveolar nerve and installation of 3 dental implants that did not reach the basal cortical bone (3.75 × 11 mm). The specimens were subjected to linear loading tests. The highest mean value of maximum load was found in G1 (412.36N ±â€Š11.99), followed by G2 (396.87N ±â€Š23.94), G3 (319.63N ±â€Š57.28), G4 (303.34N ±â€Š18.25), G5 (231.75N ±â€Š63.64) and G6 (228.13N ±â€Š20.75). Based on this data, it can be concluded that the bicorticalization (or not) of the implants was not a statistically significant risk factor for the vertical displacement of polyurethane hemi-mandibles.

Piezoelectric Surgery in the Inferior Alveolar Nerve Lateralization With Simultaneous Implant Placement: A Case Report.

The aim of this case report was to describe the inferior alveolar nerve (IAN) lateralization technique using the piezoelectric device for the posterior rehabilitation of an atrophic mandible with implants. The patient presented the absence of elements 35 and 36 associated with a vertical defect impairing the adequate dental implant placement without IAN damage. A full-thickness mucoperiosteal flap was raised, and a bone window was made with a piezoelectric device centralized on the IAN canal position. After dissection, the IAN was moved buccally with a sterile elastic strip. Morse cone 4.0 × 1.5-mm implants were inserted while the IAN remained retracted. At the 4-month follow-up, the screw-retained prosthesis was installed guaranteeing the recovering masticatory function. In conclusion, the case report showed that the IAN lateralization performed with an adequate surgical technique can be successfully indicated for longer implant placement in edentulous atrophic posterior mandible with no permanent neural damage.

Malignant Peripheral Nerve Sheath Tumor in the Course of the Mandibular Nerve.

OBJECTIVE: Malignant peripheral nerve sheath tumors are infiltrating, aggressive tumors that are soft tissue sarcomas. This article describes 3 patients with a tumorous swelling in the entire inferior alveolar nerve suspicious for malignant peripheral nerve sheath tumor, which is particularly rare in the trigeminal nerve. Diagnostic tools, surgical proceedings, and reconstructive procedures are presented. METHODS: Three male patients (age range, 58-68 years) with numbness, pain, and mild swelling in the sensory area served by the mental nerve presented to the Department of Oral and Maxillofacial Surgery and underwent diagnostic work-up including computed tomography, magnetic resonance imaging, fluorodeoxyglucose-positron emission tomography/computed tomography, and biopsy of the clinically visible tumor mass with histopathologic and molecular pathologic analysis. RESULTS: Magnetic resonance imaging revealed the full extent of the tumor comprising the course of the entire mandibular nerve (1 case bilateral) starting in the trigeminal ganglion through the inferior alveolar nerve and ending in the mental foramen. Both a neurosurgical and a maxillofacial intervention with jaw replacement were necessary. Adjuvant radiation of intracranial closed resection margins and, in 1 case, of parts of the mandible was required. CONCLUSIONS: To reveal the full extent of tumor spread of malignant peripheral nerve sheath tumors, sufficient preoperative imaging is crucial, as it is an important step in therapy planning. Magnetic resonance imaging and positron emission tomography/computed tomography have the best prospect of success in depicting the full extent of disease. Radical surgical management is the treatment of choice, whereas radiochemotherapy has an ancillary part.

Description of a new approach for great auricular and auriculotemporal nerve blocks: A cadaveric study in foxes and dogs.

Otitis externa is a painful condition that may require surgical intervention in dogs. A balanced analgesia protocol should combine systemic analgesic agents and local anaesthesia techniques. The aim of the study was to find anatomical landmarks for the great auricular and the auriculotemporal nerves that transmit nociceptive information from the ear pinna and to develop the optimal technique for a nerve block. The study consisted of two phases. In phase I, one fox cadaver was used for dissection and anatomical localization of the auricular nerves to derive landmarks for needle insertion. Eight fox cadavers were subsequently used to evaluate the accuracy of the technique by injecting methylene blue bilaterally. In phase II findings from phase I were applied in four Beagle canine cadavers. A block was deemed successful if more than 0.6 cm of the nerve's length was stained. Successful great auricular nerve block was achieved by inserting the needle superficially along the wing of the atlas with the needle pointing towards the jugular groove. For the auriculotemporal nerve block the needle was inserted perpendicular to the skin at the caudal lateral border of the zygomatic arch, close to the temporal process. The overall success rate was 24 out of 24 (100%) and 22 out of 24 (91%) for the great auricular and the auriculotemporal nerves, respectively, while the facial nerve was stained on three occasions. Our results suggest that it is feasible to achieve a block of the auricular nerves, based on anatomical landmarks, without concurrently affecting the facial nerve.

Peripheral Glial Cell Line-Derived Neurotrophic Factor Facilitates the Functional Recovery of Mechanical Nociception Following Inferior Alveolar Nerve Transection in Rats.

AIMS: To identify endogenous sources of glial cell line-derived neurotrophic factor (GDNF) at the injury site following inferior alveolar nerve transection (IANX) and to determine whether GDNF signaling promotes the recovery of orofacial pain sensation. METHODS: Nociceptive mechanical sensitivity of the facial skin was assessed following IANX (n = 10) or sham operation (n = 7). GDNF-positive cells were identified and the amount of GDNF measured in the injured region of IANX rats (n = 10) and in sham rats (n = 10). The number of trigeminal ganglion neurons with regenerated axons and the nociceptive mechanical sensitivity after continuous GDNF administration at the injury site were also assessed in IANX (n = 28) and sham (n = 12) rats. The effect of GDNF neutralization on nociceptive mechanical sensitivity at the injury site was evaluated using a neutralizing antibody (GFRα1 Nab) in four groups: IANX + phosphate-buffered saline (PBS) (n = 6); sham (n = 12); IANX + GDNF (n = 12); and IANX + GDNF + GFRα1 Nab (n = 12). Statistical analyses included one-way and two-way repeated measures analysis of variance followed by post hoc tests or unpaired t tests. The threshold for statistical significance was set at P < .05. RESULTS: Nociceptive mechanical sensitivity was lost over the 5 days following IANX and was recovered by day 13. GDNF was expressed in infiltrating inflammatory cells and had enhanced expression. GDNF administration enhanced axonal regeneration and recovery of nociceptive mechanical sensitivity. GDNF neutralization inhibited the recovery of nociceptive mechanical sensitivity after IANX. CONCLUSION: GDNF signaling at the injury site facilitates the functional recovery of mechanical nociception following IANX and is an attractive therapeutic target for the functional disturbance of pain sensation.

Role of the Inferior Alveolar Nerve in Rodent Lower Incisor Stem Cells.

In developing teeth, the sequential and reciprocal interactions between epithelial and mesenchymal tissues promote stem/progenitor cell differentiation. However, the origin of the stem/progenitor cells has been the subject of considerable debate. According to recent studies, mesenchymal stem cells originate from periarterial cells and are regulated by neurons in various organs. The present study examined the role of innervation in tooth development and rodent incisor stem/progenitor cell homeostasis. Rodent incisors continuously grow throughout their lives, and the lower incisors are innervated by the inferior alveolar nerve (IAN). In this study, we resected the IAN in adult rats, and the intact contralateral side served as a nonsurgical control. Sham control rats received the same treatment as the resected rats, except for the resection process. The extent of incisor eruption was measured, and both mesenchymal and epithelial stem/progenitor cells were visualized and compared between the IAN-resected and sham-operated groups. One week after surgery, the IAN-resected incisors exhibited a chalky consistency, and the eruption rate was decreased. Micro-computed tomography and histological analyses performed 4 wk after surgery revealed osteodentin formation, disorganized ameloblast layers, and reduced enamel thickness in the IAN-resected incisors. Immunohistochemical analysis revealed a reduction in the CD90- and LRIG1-positive mesenchymal cell ratio in the IAN-resected incisors. However, the p40-positive epithelial stem/progenitor cell ratio was comparable between the 2 groups. Thus, mesenchymal stem/progenitor cell homeostasis is more related to IAN innervation than to epithelial stem/progenitor cells. Furthermore, sensory nerve innervation influences subsequent incisor growth and formation.

Intraoperative monitoring of marginal mandibular nerve during neck dissection.

BACKGROUND: The purpose of this study was to assess the efficacy of intraoperative nerve integrity monitoring (NIM) to prevent marginal mandibular nerve injuries during neck dissection. METHODS: This prospective study compared 36 patients undergoing NIM-assisted neck dissection from July 2014 to March 2015 to a cohort of 35 patients subjected to neck dissection over an identical period of time before the technique was introduced. We also assessed possible correlations between marginal mandibular nerve injuries and other factors, such as anthropometric measurements, presence of clinical neck metastases, type of neck dissection, and site of primary tumor. RESULTS: The incidence of marginal mandibular nerve paralyses was significantly lower among the group of patients undergoing NIM-assisted neck dissection (P = .021). There was no significant difference in the duration of the procedure, and the technique resulted in a limited increase of cost. No other factor seemed to influence the onset of marginal mandibular nerve palsy. CONCLUSION: In our opinion, NIM is a valuable aid for preventing marginal mandibular nerve injuries during neck dissection.

The Risk Factors that Can Increase Possibility of Mandibular Canal Wall Damage in Adult: A Cone-Beam Computed Tomography (CBCT) Study in a Chinese Population.

BACKGROUND The objective of this study was to analyze the factors that can increase the possibility of mandibular canal (MC) defect in Chinese people, to evaluate the risk of nerve impairment, and to choose the proper operative method to reduce the risk of mandibular alveolar nerve injury during the extraction of mandibular third molar (MTM). MATERIAL AND METHODS A total of 954 patients (1,304 MTMs) who underwent orthopantomography (OPG) and cone-beam computed tomography (CBCT) between July 2014 and December 2014 were included in this study. The age and gender of patients, impacted type (high impaction, moderate impaction, and low impaction), Winter classification of MTM, position of MTM relative to MC, vertical classification of MTM and MC, and the feature images of OPG were collected and compared to the imperfection of the MC wall in CBCT images. RESULTS The wall situation of MC was significantly correlated with the age of the patient, the depth of the molar, the position of the roots, and six imaging appearances on OPG. There was no significant difference based on gender. CONCLUSIONS Most incomplete walls of MCs could be inferred by OPG. However, images based on CBCT could clarify the defect of the MC and also could clearly display the spatial relationship between the root and inferior alveolar canal.

The course and distribution of the buccal nerve: clinical relevance in dentistry.

BACKGROUND: The buccal branch of the mandibular division of the trigeminal nerve is commonly anaesthetized for dental procedures and may be damaged during surgery. Descriptions of the distribution of the buccal nerve (BN) in anatomical texts are generally lacking in detail and do not provide information about the extent of its variation between individuals. There are also commonly-held clinical beliefs about the BN that lack support from anatomical dissections. METHODS: Detailed dissections of the course and distribution of the BN were performed in a sample of 12 hemi-heads from 11 edentulous and partially dentate human adult cadavers. RESULTS: A broader distribution of the BN was found than described previously, with innervation extending to the lips in all cases. Approximately half of the lateral sides of the lips were innervated by the BN in two cases and approximately one-third of their lateral sides in the other 10 cases. Distribution of the BN to the lower lips was wider than to the upper lips. CONCLUSIONS: Our findings provide a stronger anatomical basis to underpin clinical procedures involving the BN and indicate that some commonly-held clinical views about this nerve are not supported by anatomical evidence.

The Status of Affected Infraorbital Nerve and Inferior Alveolar Nerve in Patients With Jaw Fibrous Dysplasia: A Clinical and Radiographic Evaluation.

The affected infraorbital nerve (IFBN) and inferior alveolar nerve (IFAN) status in patients with jaw fibrous dysplasia has not been definitely depicted. In this study, the authors try to explore the status of affected IFBN and IFAN in patients with jaw fibrous dysplasia. Ten patients with jaw fibrous dysplasia were included in this study. The complaints of numbness in the IFBA and IFAN innervated area were asked and recorded, and careful clinical examination was performed to evaluate the touch sense, pain sense, pressure sense, and temperature sense in the IFBA and IFAN innervated areas. Computed tomography scans also were performed to evaluate the imaging characteristics of affected IFBA and IFAN. The results showed that 1 patient with maxillary lesion showed complaints of slight numbness, and clinical examination showed that the patient exhibited slight insensitive in pain sense. In addition, 1 patient with mandibular lesion showed relative obvious complaints of numbness, and clinical examination showed that the patient exhibited slight insensitive in pain sense and temperature sense, but not serious. All other patients exhibited no numbness in the IFBA and IFAN innervated area. Although the position and morphology changed in some patients, all neural canal of affected IFBA or IFAN existed and showed no invasion of lesion. Taking these findings together, it further confirmed that evaluation of the function of IFBAN and IFAN is necessary for patients with jaw fibrous dysplasia, and the affected IFBAN and IFAN may should be reserved in most patients with jaw fibrous dysplasia when resecting or recontouring the lesion.

Peripheral Brain-Derived Neurotrophic Factor Modulates Regeneration Following Inferior Alveolar Nerve Injury in Rats.

AIMS: To examine the effects of local brain-derived neurotrophic factor (BDNF) produced after nerve injury on the functional regeneration of the damaged nerve. METHODS: The inferior alveolar nerve was transected in adult male rats and 1 µg or 10 µg of BDNF antibody was administered at the injury site; a third group of rats received saline and a fourth group underwent nerve ligation. BDNF mRNA was quantified in the transected tissue and trigeminal ganglion by using real-time polymerase chain reaction (PCR). Head withdrawal thresholds following mechanical (tactile) stimulation (with von Frey filaments) of the mental region were measured for 3 weeks postoperatively. Electromyographic activity of the jaw opening reflex (JOR) was recorded from the anterior belly of the digastric muscle. RESULTS: Within 24 hours, transection induced significant elevation of BDNF mRNA expression in the injured tissue (unpaired t test, P < .01). The head withdrawal threshold to mechanical stimulation increased at 1 day after transection and then decreased (two-way repeated measures analysis of variance [ANOVA], P < .001). At 2 weeks after surgery, the head withdrawal threshold was higher than before surgery in the group that received a higher dose of BDNF antibody (ANOVA, P < .001), but not in the group that received a smaller dose (ANOVA, P > .05). No significant differences were observed in the latency or threshold of the JOR between saline- and antibody-treated rats (unpaired t test, P > .05). CONCLUSION: These results suggest that locally administered BDNF antibody neutralizes nerve injury-induced BDNF at the injury site and thus influences sensorimotor recovery.

Somatosensory Evoked Potentials of Inferior Alveolar Nerve: confirmation of a possible non-invasive neurophysiological approach.

INTRODUCTION: The use of inferior alveolar nerve (IAN) somatosensory evoked potentials (SEPs) may represent a non-invasive method to evaluate the sensory nerve function in the maxillofacial region. The aim of this work is to confirm the feasibility of a technique, previously reported in the literature, and the data previously obtained. MATERIALS AND METHODS: SEPs were obtained following electrical stimulation (square wave pulses 0.2 millisecond [ms] in duration, 4 to 6.5 mA, 0.7/second repetition rate, 200 averages) of the gum at the mental foramen level, in the IAN region, via a new designed type of intraoral surface electrodes and recorded from the contralateral central scalp sites. RESULTS: We recognized waveforms of sufficient quality and consistently recorded a "W"-shaped response. Peak latencies of waves were at 14, 20, 27, 34 and 43 ms respectively. One side of the lower lip can be compared with the contralateral side. CONCLUSIONS: IAN SEPs, obtained with the present technique, may represent an objective, non-invasive, and reliable way of testing sensory nerve function in the maxillofacial region.

The use of piezoelectric surgery to lateralize the inferior alveolar nerve with simultaneous implant placement and immediate buccal cortical bone repositioning: a prospective clinical study.

A prospective study was conducted to assess a variation of inferior alveolar nerve (IAN) lateralization. This study included 13 patients. An osteotomy was made with a piezoelectric device, and the IAN bundle was moved buccally. Dental implants were then inserted medial to the nerve bundle, and the inner surface of the buccal cortical bone plate was shaped to reduce its thickness. Finally, the bone plate was repositioned to restore the original shape and contour of the mandible. Neurosensory examinations of the lower lip and chin were performed using three tests: light touch, pain, and two-point discrimination. Three months after surgery, the function of the IAN was judged to be completely restored at 11 of the 13 surgical sites. Differences in the tests comparing the operated and non-operated sides were not significant. No implants were lost, and all patients were satisfied with the result. Although IAN lateralization in conjunction with dental implant placement is rarely indicated, the use of a piezoelectric device to perform a buccal osteotomy with final repositioning of the buccal cortical plate over the bony defect contributes to the recovery of the contour and shape of the mandible, without impairment of IAN function.