Furlow术式及改良兰式修复浅Ⅱ度腭裂的临床研究

目的对比Furlow术式及改良兰式对浅Ⅱ度腭裂的修复效果,评价这两种手术方式对于修复此类腭裂的优劣。方法 50例浅Ⅱ度腭裂患者随机分成两组,A组使用Furlow术式,B组使用改良兰式,对比两组患者的术后软腭延长长度、手术时间、术中出血量、术后3 d平均体温及术后语音改善的程度。结果两种术式在术后软腭延长长度方面,Furlow术式优于改良兰式,前者为(0.794±0.198)cm,后者为(0.118±0.076)cm,差异有统计学意义(t=15.928,P<0.001)。手术时间、术中出血量、术后3 d平均体温及术后语音改善程度,2种术式差异无统计学意义(P>0.05)。结论两种术式均可用于浅Ⅱ度腭裂的修复,但Furlow术式在延长软腭方面优势明显,对于不同类型腭裂可选用个体化修复方案。     

骨水平Xive种植体系统用于前牙美学修复的临床研究

目的:美学效果是种植修复追求的目标之一,相比功能方面的修复成功而言,实现美学方面的修复成功要更为困难,通常需要较为复杂的手术处理。本研究采用一种微创手术模式和简化的修复治疗程序,在前牙区植入骨水平种植体,评价其美学效果。方法:16例前牙缺失患者纳入本研究。所有患者经过全面检查,并做美学风险评估。采用不翻瓣加骨膨胀手术方法植入Xi ve骨水平种植体,术后连接基台,制作树脂牙冠即刻完成临时修复。四个月后更换为烤瓷牙冠完成恒久修复。观察种植体周硬软组织的变化,并对最终美学修复效果做临床评价。结果:16例患者所植入的22枚种植体在平均观察期8.3个月(5-24个月)无松动脱落。所有患者对修复结果都高度满意。种植修复的白色美学效果,受制于技工制作水平显得不太理想,而粉红色美学效果与患者组织条件有关,但与术前比较,种植体区硬软组织均有明显改善。结论:种植即刻暂时修复体,既可以满足患者美观需要,又对软组织实施了诱导成形。不翻瓣加骨膨胀手术方法,有利于增加种植体区硬软组织量,减少骨吸收,避免牙龈退缩,并避免牙龈组织的瘢痕形成,有利于获得较好的健康的软组织美学,其远期效果还有待继续观察。     

Numerical analysis of the biomechanical behaviour of a weakened root after adhesive reconstruction and post-core rehabilitation

Objectives

The purpose of this study was to perform a finite element analysis to determine whether adhesive reconstruction is able to restore the original biomechanical behaviour of weakened roots, in terms of fracture resistance, when compared with post/crown-restored teeth with intact roots.

Methods

A three-dimensional model of a maxillary central incisor was created. The model simulated an endodontically treated tooth restored with a glass-fibre post, a composite-resin core and a metal crown (Model 1). Based on Model 1, a new volume was created in the root cervical third that represented the area where the dentine structure was lost, resulting in a structurally damaged root (Model 2). A 100 N load was applied to the palatal surface at 130° from the long axis of the tooth. After processing (Ansys^® 10.0 – Canonsburg, PA, USA), the principal normal stress data were analyzed (S1, tensile; S3, compressive).

Results

The models demonstrated a similar S1 distribution concentrated in the lingual cervical region but different S1 levels (Model 1: 28.7 MPa; Model 2: 35.3 MPa). The S3 distribution indicated differences in behaviour between the models (Model 1: −18 to −27 MPa along the buccal root surface; Model 2: −25 to −32 MPa on the post buccal surface and along the buccal root wall).

Conclusions

Although the stress distribution within the root walls remained below the ultimate stress limit of the root dentine, the adhesive reconstruction of the weakened roots did not recover the load resistance of structurally intact roots.

Clinical significance

The decision of when to prosthetically rehabilitate weakened roots with cervical dentine structural tissue loss is a challenge for clinicians. A ‘monoblock’ adhesive reconstruction has been proposed for root reinforcement. During treatment planning, the possibility of restoring the mechanical resistance of the root must be evaluated if successful long-term results are to be achieved.     

The Impact of Dopamine on Hemodynamics,Oxygen Metabolism,and Cerebral Resuscitation After Restoration of Spontaneous Circulation in Pigs

Background: Restoration of spontaneous circulation after cardiopulmonary resuscitation in cardiac arrest patients does not always signal a completely successful outcome. Functional deficiencies of the nervous system are found in many survivors of cardiac arrest. Objectives: To study the effects of dopamine-induced elevated blood pressure on the hemodynamics, oxygen metabolism, and cerebral resuscitation in different perfusion conditions in a resuscitated animal model. Methods: There were 18 pigs included in the study. Ventricular fibrillation (VF) was induced with a programmed electrical stimulation device. After 4 min of untreated ventricular fibrillation followed by 9 min of CPR, 12 animals were resuscitated successfully, and were then randomly assigned to either the study group (dopamine group) or the control group (normal perfusion group). All animals in the two groups received normal saline through continuous intravenous guttae for 4 h at a rate of 15 mL/kg/h. In the study group, dopamine was added to raise the animals' blood pressure. Four hours of intensive monitoring was performed for all study animals. Finally, 24-h evaluation of neurological function was conducted in surviving animals in accordance with the standard of the Cerebral Performance Category Score. Results: In animals in the dopamine group, the cardiac output, mean aortic pressure, coronary perfusion pressure, oxygen delivery, and oxygen consumption were higher than those found in the animals in the normal perfusion group (p < 0.05). Oxygen metabolism was remarkably improved in animals in the dopamine group. Furthermore, cerebral perfusion was better in the dopamine group than in the control group and thus, results of the evaluation of nervous system function were better in animals treated with dopamine (p < 0.05). Conclusions: Dopamine improved systemic perfusion, cerebral blood supply, and oxygen metabolism after successful resuscitation from VF in a porcine model. All of these factors have profound effects on the cerebral resuscitation.     

影响视神经修复再生的因素

视神经作为中枢神经的代表，其损伤后的修复再生一直是近年来研究的热点。综述相关研究文献，旨在了解视神经损伤后修复再生的相关因素。以期为该病的治疗提供新的思路与方法。     

Neuroprotective ferulic acid (FA)–glycol chitosan (GC) nanoparticles for functional restoration of traumatically injured spinal cord

An urgent unmet need exists for early-stage treatment of spinal cord injury (SCI). Currently methylprednisolone is the only therapeutic agent used in clinics, for which the efficacy is controversial and the side effect is well-known. We demonstrated functional restoration of injured spinal cord by self-assembled nanoparticles composed of ferulic acid modified glycol chitosan (FA–GC). Chitosan and ferulic acid are strong neuroprotective agents but their systemic delivery is difficult. Our data has shown a prolonged circulation time of the FA–GC nanoparticles allowing for effective delivery of both chitosan and ferulic acid to the injured site. Furthermore, the nanoparticles were found both in the gray matter and white matter. The in vitro tests demonstrated that nanoparticles protected primary neurons from glutamate-induced excitotoxicity. Using a spinal cord contusion injury model, significant recovery in locomotor function was observed in rats that were intravenously administered nanoparticles at 2 h post injury, as compared to non-improvement by methylprednisolone administration. Histological analysis revealed that FA–GC treatment significantly preserved axons and myelin and also reduced cavity volume, astrogliosis, and inflammatory response at the lesion site. No obvious adverse effects of nanoparticles to other organs were found. The restorative effect of FA–GC presents a promising potential for treating human SCIs.