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21.
Fractures through the mandible at the level of the parasymphysis extending obliquely and traversing through the transitional zone to body region are relatively common. Therefore, a surgeon should have an appropriate understanding of the biomechanics of different plating techniques to fix these fractures. There is always a dilemma for the surgeon as to whether to fix these mandibular segments with one or two miniplates, and the presence of mental neurovascular bundle makes it more challenging. A study was planned in the Department of Oral and Maxillofacial Surgery to evaluate a novel twin-fork design of a miniplate used for fracture fixation at the transition zone of parasymphysis and body region of mandible after an in-vitro study of same design, and provided encouraging results. A total of 30 patients (10 patients in three groups each) were included in the study. All patients were evaluated preoperatively and postoperatively for operating time, ease of placement of miniplate, occlusion, reduction of fracture, neurosensory disturbances and infection. The novel design of twin-fork−shaped miniplate proved to be superior to the conventional miniplate in terms of neurosensory (Fisher exact test 17.40; p = 0.003) and functional outcome. There was statistically significant difference (χ2 = 13.895, p = 0.031) in postoperative reduction of fracture at week 4, indicating superiority of the twin-fork miniplate among the other conventional designs. The study concludes that the use of newly designed twin-fork−shaped miniplate should be encouraged in the fractures of transitional zone of parasymphysis-body region involving mental neurovascular bundle.  相似文献   
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The inferior alveolar nerve and facial nerve are the two most important nerves in the dental and maxillofacial region. The injury to them is one of the major postoperative complications after alveolar surgery and orthognathic surgery. However, recovering the nerve function after injury takes a long time and the recovery effect tends to be unsatisfactory. In recent years, an intensively investigated technique, low level laser which has been applying in assisting the recovery of nerve function, has been gradually proved to be effective in clinically treating postoperative nerve injury. In this article we review in terms of the mechanisms involved in low level laser-assisted functional restoration of nerve injury and its clinical application in the recovery of nerve function in the dental and maxillofacial area as well.  相似文献   
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《The Journal of arthroplasty》2022,37(10):1922-1927.e2
BackgroundRegional nerve blocks may be used as a component of a multimodal analgesic protocol to manage postoperative pain after primary total hip arthroplasty (THA). The purpose of our study was to evaluate the efficacy and safety of regional nerve blocks after THA in support of the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and American Society of Regional Anesthesia and Pain Management.MethodsWe searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials for studies published prior to March 24, 2020 on fascia iliaca, lumbar plexus, and quadratus lumborum blocks in primary THA. All included studies underwent qualitative and quantitative homogeneity testing followed by a systematic review and direct comparison meta-analysis to assess the efficacy and safety of the regional nerve blocks.ResultsAn initial critical appraisal of 3,382 publications yielded 11 publications representing the best available evidence for an analysis. Fascia iliaca, lumbar plexus, and quadratus lumborum blocks demonstrate the ability to reduce postoperative pain and opioid consumption. Among the available comparisons, no difference was noted between a regional nerve block or local periarticular anesthetic infiltration regarding postoperative pain and opioid consumption.ConclusionLocal periarticular anesthetic infiltration should be considered prior to a regional nerve block due to concerns over the safety and cost of regional nerve blocks. If a regional nerve block is used in primary THA, a fascia iliaca block is preferred over other blocks due to the differences in technical demands and risks associated with the alternative regional nerve blocks.  相似文献   
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Background

There is a need for a peripheral nerve model on which surgeons-in-training can simulate the repair of nerve injuries at their own pace. Although practicing on animal models/cadavers is considered the “gold standard” of microsurgical training, the proposed model aims to provide a platform for improving the technical skills of surgical trainees prior to their practice on cadaver/animal models. In addition, this model has the potential to serve as a standardized test medium for assessing the skill sets of surgeons.

Methods

Several formulations of silicone were utilized for the design and fabrication of a model which realizes the hierarchical structure of peripheral nerves. The mechanical properties were characterized via the Universal Testing Machine; the damage caused by the needle on the entry sites was assessed through scanning electron microscopy (SEM).

Results

Mechanical properties of the formulations of silicone were tested to mimic human peripheral nerves. A formulation with 83.3?wt% silicone oil and 0.1?wt% cotton fiber was chosen to be used as nerve fascicles. Both 83.3?wt% silicone oil with cotton fiber and 66.6?wt% silicone oil without fiber provided a microsuturing response similar to that of epineurium at a wall thickness of 1?mm. SEM also confirmed that the entry of the needle did not introduce significant holes at the microsuturing sites.

Conclusions

The proposed peripheral nerve model mimicked human tissues mechanically and cosmetically, and a simulation of the repair of a fifth-degree nerve injury was achieved.  相似文献   
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Background

The efficacy of dexamethasone in extending the duration of local anaesthetic block is uncertain. In a randomised controlled triple blind crossover study in volunteers, we tested the hypothesis that neither i.v. nor perineurally administered dexamethasone prolongs the sensory block achieved with ropivacaine.

Methods

Ultrasound-guided ulnar nerve blocks (ropivacaine 0.75% wt/vol, 3 ml, with saline 1 ml with or without dexamethasone 4 mg) were performed on three occasions in 24 male volunteers along with an i.v. injection of saline 1 ml with or without dexamethasone 4 mg. The combinations of saline and dexamethasone were as follows: control group, perineural and i.v. saline; perineural group, perineural dexamethasone and i.v. saline; i.v. group, perineural saline and i.v. dexamethasone. Sensory block was measured using a VAS in response to pinprick testing. The duration of sensory block was the primary outcome and time to onset of sensory block the secondary outcome.

Results

All 24 subjects completed the trial. The median [inter-quartile range (IQR)] duration of sensory block was 6.87 (5.85–7.62) h in the control group, 7.37 (5.78–7.93) h in the perineural group and 7.37 (6.10–7.97) h in the i.v. group (P=0.61). There was also no significant difference in block onset time between the three groups.

Conclusion

Dexamethasone 4 mg has no clinically relevant effect on the duration of sensory block provided by ropivacaine applied to the ulnar nerve.

Clinical trial registration

DRKS, 00014604; EudraCT, 2018-001221-98.  相似文献   
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目的探讨腮腺切除术中应用沿面神经总干顺行解剖面神经的治疗效果及安全性。方法选取我院2016年2月至2019年3月收治的60例择期行腮腺切除术的患者,随机分为观察组与对照组各30例。对照组沿面神经总干逆行解剖面神经,观察组沿面神经总干顺行解剖面神经,观察两组患者术后1个月面神经功能及术后并发症发生情况。结果术后1个月,两组患者的面神经功能分级比较无统计学差异(P>0.05);观察组的术后并发症发生率为10.00%,明显低于对照组的33.33%(P <0.05)。结论临床行腮腺切除术中,沿面神经总干顺行解剖面神经可降低术后并发症发生率,值得推广。  相似文献   
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